eb1843e8af
654 Commits
| Author | SHA1 | Message | Date | |
|---|---|---|---|---|
Greg Kroah-Hartman
|
836d95bfdc |
This is the 5.4.207 stable release
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||
Linus Torvalds
|
cbc98dcc38 |
signal handling: don't use BUG_ON() for debugging
[ Upstream commit a382f8fee42ca10c9bfce0d2352d4153f931f5dc ] These are indeed "should not happen" situations, but it turns out recent changes made the 'task_is_stopped_or_trace()' case trigger (fix for that exists, is pending more testing), and the BUG_ON() makes it unnecessarily hard to actually debug for no good reason. It's been that way for a long time, but let's make it clear: BUG_ON() is not good for debugging, and should never be used in situations where you could just say "this shouldn't happen, but we can continue". Use WARN_ON_ONCE() instead to make sure it gets logged, and then just continue running. Instead of making the system basically unusuable because you crashed the machine while potentially holding some very core locks (eg this function is commonly called while holding 'tasklist_lock' for writing). Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org> |
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|
Greg Kroah-Hartman
|
91a7552bea |
This is the 5.4.160 stable release
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Merge 5.4.160 into android11-5.4-lts
Changes in 5.4.160
xhci: Fix USB 3.1 enumeration issues by increasing roothub power-on-good delay
usb: xhci: Enable runtime-pm by default on AMD Yellow Carp platform
binder: use euid from cred instead of using task
binder: use cred instead of task for selinux checks
binder: use cred instead of task for getsecid
Input: iforce - fix control-message timeout
Input: elantench - fix misreporting trackpoint coordinates
Input: i8042 - Add quirk for Fujitsu Lifebook T725
libata: fix read log timeout value
ocfs2: fix data corruption on truncate
scsi: qla2xxx: Fix kernel crash when accessing port_speed sysfs file
scsi: qla2xxx: Fix use after free in eh_abort path
mmc: dw_mmc: Dont wait for DRTO on Write RSP error
parisc: Fix ptrace check on syscall return
tpm: Check for integer overflow in tpm2_map_response_body()
firmware/psci: fix application of sizeof to pointer
crypto: s5p-sss - Add error handling in s5p_aes_probe()
media: ite-cir: IR receiver stop working after receive overflow
media: ir-kbd-i2c: improve responsiveness of hauppauge zilog receivers
media: v4l2-ioctl: Fix check_ext_ctrls
ALSA: hda/realtek: Add quirk for Clevo PC70HS
ALSA: hda/realtek: Add a quirk for Acer Spin SP513-54N
ALSA: hda/realtek: Add quirk for ASUS UX550VE
ALSA: hda/realtek: Add quirk for HP EliteBook 840 G7 mute LED
ALSA: ua101: fix division by zero at probe
ALSA: 6fire: fix control and bulk message timeouts
ALSA: line6: fix control and interrupt message timeouts
ALSA: usb-audio: Add registration quirk for JBL Quantum 400
ALSA: synth: missing check for possible NULL after the call to kstrdup
ALSA: timer: Fix use-after-free problem
ALSA: timer: Unconditionally unlink slave instances, too
fuse: fix page stealing
x86/sme: Use #define USE_EARLY_PGTABLE_L5 in mem_encrypt_identity.c
x86/cpu: Fix migration safety with X86_BUG_NULL_SEL
x86/irq: Ensure PI wakeup handler is unregistered before module unload
cavium: Return negative value when pci_alloc_irq_vectors() fails
scsi: qla2xxx: Return -ENOMEM if kzalloc() fails
scsi: qla2xxx: Fix unmap of already freed sgl
cavium: Fix return values of the probe function
sfc: Don't use netif_info before net_device setup
hyperv/vmbus: include linux/bitops.h
ARM: dts: sun7i: A20-olinuxino-lime2: Fix ethernet phy-mode
reset: socfpga: add empty driver allowing consumers to probe
mmc: winbond: don't build on M68K
drm: panel-orientation-quirks: Add quirk for Aya Neo 2021
bpf: Define bpf_jit_alloc_exec_limit for arm64 JIT
bpf: Prevent increasing bpf_jit_limit above max
xen/netfront: stop tx queues during live migration
nvmet-tcp: fix a memory leak when releasing a queue
spi: spl022: fix Microwire full duplex mode
net: multicast: calculate csum of looped-back and forwarded packets
watchdog: Fix OMAP watchdog early handling
drm: panel-orientation-quirks: Add quirk for GPD Win3
nvmet-tcp: fix header digest verification
r8169: Add device 10ec:8162 to driver r8169
vmxnet3: do not stop tx queues after netif_device_detach()
nfp: bpf: relax prog rejection for mtu check through max_pkt_offset
net/smc: Correct spelling mistake to TCPF_SYN_RECV
btrfs: clear MISSING device status bit in btrfs_close_one_device
btrfs: fix lost error handling when replaying directory deletes
btrfs: call btrfs_check_rw_degradable only if there is a missing device
ia64: kprobes: Fix to pass correct trampoline address to the handler
hwmon: (pmbus/lm25066) Add offset coefficients
regulator: s5m8767: do not use reset value as DVS voltage if GPIO DVS is disabled
regulator: dt-bindings: samsung,s5m8767: correct s5m8767,pmic-buck-default-dvs-idx property
EDAC/sb_edac: Fix top-of-high-memory value for Broadwell/Haswell
mwifiex: fix division by zero in fw download path
ath6kl: fix division by zero in send path
ath6kl: fix control-message timeout
ath10k: fix control-message timeout
ath10k: fix division by zero in send path
PCI: Mark Atheros QCA6174 to avoid bus reset
rtl8187: fix control-message timeouts
evm: mark evm_fixmode as __ro_after_init
wcn36xx: Fix HT40 capability for 2Ghz band
mwifiex: Read a PCI register after writing the TX ring write pointer
libata: fix checking of DMA state
wcn36xx: handle connection loss indication
rsi: fix occasional initialisation failure with BT coex
rsi: fix key enabled check causing unwanted encryption for vap_id > 0
rsi: fix rate mask set leading to P2P failure
rsi: Fix module dev_oper_mode parameter description
RDMA/qedr: Fix NULL deref for query_qp on the GSI QP
signal: Remove the bogus sigkill_pending in ptrace_stop
signal/mips: Update (_save|_restore)_fp_context to fail with -EFAULT
power: supply: max17042_battery: Prevent int underflow in set_soc_threshold
power: supply: max17042_battery: use VFSOC for capacity when no rsns
KVM: nVMX: Query current VMCS when determining if MSR bitmaps are in use
can: j1939: j1939_tp_cmd_recv(): ignore abort message in the BAM transport
can: j1939: j1939_can_recv(): ignore messages with invalid source address
powerpc/85xx: Fix oops when mpc85xx_smp_guts_ids node cannot be found
serial: core: Fix initializing and restoring termios speed
ALSA: mixer: oss: Fix racy access to slots
ALSA: mixer: fix deadlock in snd_mixer_oss_set_volume
xen/balloon: add late_initcall_sync() for initial ballooning done
PCI: pci-bridge-emul: Fix emulation of W1C bits
PCI: aardvark: Do not clear status bits of masked interrupts
PCI: aardvark: Fix checking for link up via LTSSM state
PCI: aardvark: Do not unmask unused interrupts
PCI: aardvark: Fix reporting Data Link Layer Link Active
PCI: aardvark: Fix return value of MSI domain .alloc() method
PCI: aardvark: Read all 16-bits from PCIE_MSI_PAYLOAD_REG
quota: check block number when reading the block in quota file
quota: correct error number in free_dqentry()
pinctrl: core: fix possible memory leak in pinctrl_enable()
iio: dac: ad5446: Fix ad5622_write() return value
USB: serial: keyspan: fix memleak on probe errors
USB: iowarrior: fix control-message timeouts
USB: chipidea: fix interrupt deadlock
dma-buf: WARN on dmabuf release with pending attachments
drm: panel-orientation-quirks: Update the Lenovo Ideapad D330 quirk (v2)
drm: panel-orientation-quirks: Add quirk for KD Kurio Smart C15200 2-in-1
drm: panel-orientation-quirks: Add quirk for the Samsung Galaxy Book 10.6
Bluetooth: sco: Fix lock_sock() blockage by memcpy_from_msg()
Bluetooth: fix use-after-free error in lock_sock_nested()
drm/panel-orientation-quirks: add Valve Steam Deck
platform/x86: wmi: do not fail if disabling fails
MIPS: lantiq: dma: add small delay after reset
MIPS: lantiq: dma: reset correct number of channel
locking/lockdep: Avoid RCU-induced noinstr fail
net: sched: update default qdisc visibility after Tx queue cnt changes
smackfs: Fix use-after-free in netlbl_catmap_walk()
x86: Increase exception stack sizes
mwifiex: Run SET_BSS_MODE when changing from P2P to STATION vif-type
mwifiex: Properly initialize private structure on interface type changes
ath10k: high latency fixes for beacon buffer
media: mt9p031: Fix corrupted frame after restarting stream
media: netup_unidvb: handle interrupt properly according to the firmware
media: stm32: Potential NULL pointer dereference in dcmi_irq_thread()
media: uvcvideo: Set capability in s_param
media: uvcvideo: Return -EIO for control errors
media: uvcvideo: Set unique vdev name based in type
media: s5p-mfc: fix possible null-pointer dereference in s5p_mfc_probe()
media: s5p-mfc: Add checking to s5p_mfc_probe().
media: imx: set a media_device bus_info string
media: mceusb: return without resubmitting URB in case of -EPROTO error.
ia64: don't do IA64_CMPXCHG_DEBUG without CONFIG_PRINTK
brcmfmac: Add DMI nvram filename quirk for Cyberbook T116 tablet
media: rcar-csi2: Add checking to rcsi2_start_receiver()
ipmi: Disable some operations during a panic
ACPICA: Avoid evaluating methods too early during system resume
media: ipu3-imgu: imgu_fmt: Handle properly try
media: ipu3-imgu: VIDIOC_QUERYCAP: Fix bus_info
media: usb: dvd-usb: fix uninit-value bug in dibusb_read_eeprom_byte()
net-sysfs: try not to restart the syscall if it will fail eventually
tracefs: Have tracefs directories not set OTH permission bits by default
ath: dfs_pattern_detector: Fix possible null-pointer dereference in channel_detector_create()
iov_iter: Fix iov_iter_get_pages{,_alloc} page fault return value
ACPI: battery: Accept charges over the design capacity as full
leaking_addresses: Always print a trailing newline
memstick: r592: Fix a UAF bug when removing the driver
lib/xz: Avoid overlapping memcpy() with invalid input with in-place decompression
lib/xz: Validate the value before assigning it to an enum variable
workqueue: make sysfs of unbound kworker cpumask more clever
tracing/cfi: Fix cmp_entries_* functions signature mismatch
mwl8k: Fix use-after-free in mwl8k_fw_state_machine()
block: remove inaccurate requeue check
nvmet: fix use-after-free when a port is removed
nvmet-tcp: fix use-after-free when a port is removed
nvme: drop scan_lock and always kick requeue list when removing namespaces
PM: hibernate: Get block device exclusively in swsusp_check()
selftests: kvm: fix mismatched fclose() after popen()
iwlwifi: mvm: disable RX-diversity in powersave
smackfs: use __GFP_NOFAIL for smk_cipso_doi()
ARM: clang: Do not rely on lr register for stacktrace
gre/sit: Don't generate link-local addr if addr_gen_mode is IN6_ADDR_GEN_MODE_NONE
ARM: 9136/1: ARMv7-M uses BE-8, not BE-32
vrf: run conntrack only in context of lower/physdev for locally generated packets
net: annotate data-race in neigh_output()
btrfs: do not take the uuid_mutex in btrfs_rm_device
spi: bcm-qspi: Fix missing clk_disable_unprepare() on error in bcm_qspi_probe()
x86/hyperv: Protect set_hv_tscchange_cb() against getting preempted
parisc: fix warning in flush_tlb_all
task_stack: Fix end_of_stack() for architectures with upwards-growing stack
parisc/unwind: fix unwinder when CONFIG_64BIT is enabled
parisc/kgdb: add kgdb_roundup() to make kgdb work with idle polling
netfilter: conntrack: set on IPS_ASSURED if flows enters internal stream state
selftests/bpf: Fix strobemeta selftest regression
Bluetooth: fix init and cleanup of sco_conn.timeout_work
rcu: Fix existing exp request check in sync_sched_exp_online_cleanup()
drm/v3d: fix wait for TMU write combiner flush
virtio-gpu: fix possible memory allocation failure
net: net_namespace: Fix undefined member in key_remove_domain()
cgroup: Make rebind_subsystems() disable v2 controllers all at once
wilc1000: fix possible memory leak in cfg_scan_result()
Bluetooth: btmtkuart: fix a memleak in mtk_hci_wmt_sync
crypto: caam - disable pkc for non-E SoCs
rxrpc: Fix _usecs_to_jiffies() by using usecs_to_jiffies()
net: dsa: rtl8366rb: Fix off-by-one bug
ath10k: Fix missing frame timestamp for beacon/probe-resp
drm/amdgpu: fix warning for overflow check
media: em28xx: add missing em28xx_close_extension
media: cxd2880-spi: Fix a null pointer dereference on error handling path
media: dvb-usb: fix ununit-value in az6027_rc_query
media: TDA1997x: handle short reads of hdmi info frame.
media: mtk-vpu: Fix a resource leak in the error handling path of 'mtk_vpu_probe()'
media: radio-wl1273: Avoid card name truncation
media: si470x: Avoid card name truncation
media: tm6000: Avoid card name truncation
media: cx23885: Fix snd_card_free call on null card pointer
kprobes: Do not use local variable when creating debugfs file
crypto: ecc - fix CRYPTO_DEFAULT_RNG dependency
cpuidle: Fix kobject memory leaks in error paths
media: em28xx: Don't use ops->suspend if it is NULL
ath9k: Fix potential interrupt storm on queue reset
EDAC/amd64: Handle three rank interleaving mode
netfilter: nft_dynset: relax superfluous check on set updates
media: dvb-frontends: mn88443x: Handle errors of clk_prepare_enable()
crypto: qat - detect PFVF collision after ACK
crypto: qat - disregard spurious PFVF interrupts
hwrng: mtk - Force runtime pm ops for sleep ops
b43legacy: fix a lower bounds test
b43: fix a lower bounds test
mmc: sdhci-omap: Fix NULL pointer exception if regulator is not configured
memstick: avoid out-of-range warning
memstick: jmb38x_ms: use appropriate free function in jmb38x_ms_alloc_host()
net, neigh: Fix NTF_EXT_LEARNED in combination with NTF_USE
hwmon: Fix possible memleak in __hwmon_device_register()
hwmon: (pmbus/lm25066) Let compiler determine outer dimension of lm25066_coeff
ath10k: fix max antenna gain unit
drm/msm: uninitialized variable in msm_gem_import()
net: stream: don't purge sk_error_queue in sk_stream_kill_queues()
mmc: mxs-mmc: disable regulator on error and in the remove function
block: ataflop: fix breakage introduced at blk-mq refactoring
platform/x86: thinkpad_acpi: Fix bitwise vs. logical warning
mt76: mt76x02: fix endianness warnings in mt76x02_mac.c
rsi: stop thread firstly in rsi_91x_init() error handling
mwifiex: Send DELBA requests according to spec
phy: micrel: ksz8041nl: do not use power down mode
nvme-rdma: fix error code in nvme_rdma_setup_ctrl
PM: hibernate: fix sparse warnings
clocksource/drivers/timer-ti-dm: Select TIMER_OF
drm/msm: Fix potential NULL dereference in DPU SSPP
smackfs: use netlbl_cfg_cipsov4_del() for deleting cipso_v4_doi
libbpf: Fix BTF data layout checks and allow empty BTF
s390/gmap: don't unconditionally call pte_unmap_unlock() in __gmap_zap()
irq: mips: avoid nested irq_enter()
tcp: don't free a FIN sk_buff in tcp_remove_empty_skb()
samples/kretprobes: Fix return value if register_kretprobe() failed
KVM: s390: Fix handle_sske page fault handling
libertas_tf: Fix possible memory leak in probe and disconnect
libertas: Fix possible memory leak in probe and disconnect
wcn36xx: add proper DMA memory barriers in rx path
drm/amdgpu/gmc6: fix DMA mask from 44 to 40 bits
net: amd-xgbe: Toggle PLL settings during rate change
net: phylink: avoid mvneta warning when setting pause parameters
crypto: pcrypt - Delay write to padata->info
selftests/bpf: Fix fclose/pclose mismatch in test_progs
udp6: allow SO_MARK ctrl msg to affect routing
ibmvnic: don't stop queue in xmit
ibmvnic: Process crqs after enabling interrupts
RDMA/rxe: Fix wrong port_cap_flags
clk: mvebu: ap-cpu-clk: Fix a memory leak in error handling paths
ARM: s3c: irq-s3c24xx: Fix return value check for s3c24xx_init_intc()
arm64: dts: rockchip: Fix GPU register width for RK3328
ARM: dts: qcom: msm8974: Add xo_board reference clock to DSI0 PHY
RDMA/bnxt_re: Fix query SRQ failure
arm64: dts: meson-g12a: Fix the pwm regulator supply properties
ARM: dts: at91: tse850: the emac<->phy interface is rmii
scsi: dc395: Fix error case unwinding
MIPS: loongson64: make CPU_LOONGSON64 depends on MIPS_FP_SUPPORT
JFS: fix memleak in jfs_mount
ALSA: hda: Reduce udelay() at SKL+ position reporting
arm: dts: omap3-gta04a4: accelerometer irq fix
soc/tegra: Fix an error handling path in tegra_powergate_power_up()
memory: fsl_ifc: fix leak of irq and nand_irq in fsl_ifc_ctrl_probe
clk: at91: check pmc node status before registering syscore ops
video: fbdev: chipsfb: use memset_io() instead of memset()
serial: 8250_dw: Drop wrong use of ACPI_PTR()
usb: gadget: hid: fix error code in do_config()
power: supply: rt5033_battery: Change voltage values to µV
scsi: csiostor: Uninitialized data in csio_ln_vnp_read_cbfn()
RDMA/mlx4: Return missed an error if device doesn't support steering
staging: ks7010: select CRYPTO_HASH/CRYPTO_MICHAEL_MIC
ARM: dts: stm32: fix SAI sub nodes register range
ASoC: cs42l42: Correct some register default values
ASoC: cs42l42: Defer probe if request_threaded_irq() returns EPROBE_DEFER
phy: qcom-qusb2: Fix a memory leak on probe
serial: xilinx_uartps: Fix race condition causing stuck TX
HID: u2fzero: clarify error check and length calculations
HID: u2fzero: properly handle timeouts in usb_submit_urb
powerpc/44x/fsp2: add missing of_node_put
mips: cm: Convert to bitfield API to fix out-of-bounds access
power: supply: bq27xxx: Fix kernel crash on IRQ handler register error
apparmor: fix error check
rpmsg: Fix rpmsg_create_ept return when RPMSG config is not defined
pnfs/flexfiles: Fix misplaced barrier in nfs4_ff_layout_prepare_ds
drm/plane-helper: fix uninitialized variable reference
PCI: aardvark: Don't spam about PIO Response Status
PCI: aardvark: Fix preserving PCI_EXP_RTCTL_CRSSVE flag on emulated bridge
opp: Fix return in _opp_add_static_v2()
NFS: Fix deadlocks in nfs_scan_commit_list()
fs: orangefs: fix error return code of orangefs_revalidate_lookup()
mtd: spi-nor: hisi-sfc: Remove excessive clk_disable_unprepare()
mtd: core: don't remove debugfs directory if device is in use
dmaengine: at_xdmac: fix AT_XDMAC_CC_PERID() macro
auxdisplay: img-ascii-lcd: Fix lock-up when displaying empty string
auxdisplay: ht16k33: Connect backlight to fbdev
auxdisplay: ht16k33: Fix frame buffer device blanking
soc: fsl: dpaa2-console: free buffer before returning from dpaa2_console_read
netfilter: nfnetlink_queue: fix OOB when mac header was cleared
dmaengine: dmaengine_desc_callback_valid(): Check for `callback_result`
signal/sh: Use force_sig(SIGKILL) instead of do_group_exit(SIGKILL)
m68k: set a default value for MEMORY_RESERVE
watchdog: f71808e_wdt: fix inaccurate report in WDIOC_GETTIMEOUT
ar7: fix kernel builds for compiler test
scsi: qla2xxx: Fix gnl list corruption
scsi: qla2xxx: Turn off target reset during issue_lip
NFSv4: Fix a regression in nfs_set_open_stateid_locked()
i2c: xlr: Fix a resource leak in the error handling path of 'xlr_i2c_probe()'
xen-pciback: Fix return in pm_ctrl_init()
net: davinci_emac: Fix interrupt pacing disable
net: vlan: fix a UAF in vlan_dev_real_dev()
ACPI: PMIC: Fix intel_pmic_regs_handler() read accesses
bonding: Fix a use-after-free problem when bond_sysfs_slave_add() failed
mm/zsmalloc.c: close race window between zs_pool_dec_isolated() and zs_unregister_migration()
zram: off by one in read_block_state()
perf bpf: Add missing free to bpf_event__print_bpf_prog_info()
llc: fix out-of-bound array index in llc_sk_dev_hash()
nfc: pn533: Fix double free when pn533_fill_fragment_skbs() fails
arm64: pgtable: make __pte_to_phys/__phys_to_pte_val inline functions
bpf: sockmap, strparser, and tls are reusing qdisc_skb_cb and colliding
net/sched: sch_taprio: fix undefined behavior in ktime_mono_to_any
net: hns3: allow configure ETS bandwidth of all TCs
vsock: prevent unnecessary refcnt inc for nonblocking connect
net/smc: fix sk_refcnt underflow on linkdown and fallback
cxgb4: fix eeprom len when diagnostics not implemented
selftests/net: udpgso_bench_rx: fix port argument
ARM: 9155/1: fix early early_iounmap()
ARM: 9156/1: drop cc-option fallbacks for architecture selection
parisc: Fix backtrace to always include init funtion names
parisc: Fix set_fixmap() on PA1.x CPUs
irqchip/sifive-plic: Fixup EOI failed when masked
f2fs: should use GFP_NOFS for directory inodes
net, neigh: Enable state migration between NUD_PERMANENT and NTF_USE
9p/net: fix missing error check in p9_check_errors
ovl: fix deadlock in splice write
powerpc/lib: Add helper to check if offset is within conditional branch range
powerpc/bpf: Validate branch ranges
powerpc/bpf: Fix BPF_SUB when imm == 0x80000000
powerpc/security: Add a helper to query stf_barrier type
powerpc/bpf: Emit stf barrier instruction sequences for BPF_NOSPEC
mm, oom: pagefault_out_of_memory: don't force global OOM for dying tasks
mm, oom: do not trigger out_of_memory from the #PF
video: backlight: Drop maximum brightness override for brightness zero
s390/cio: check the subchannel validity for dev_busid
s390/tape: fix timer initialization in tape_std_assign()
s390/cio: make ccw_device_dma_* more robust
powerpc/powernv/prd: Unregister OPAL_MSG_PRD2 notifier during module unload
PCI: Add PCI_EXP_DEVCTL_PAYLOAD_* macros
SUNRPC: Partial revert of commit 6f9f17287e78
ath10k: fix invalid dma_addr_t token assignment
selftests/bpf: Fix also no-alu32 strobemeta selftest
Linux 5.4.160
Note, binder* patches were manually reverted as part of this merge, they
are not present in this merge point at all.
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
Change-Id: I1fb759dd89408adbe9b9ac1527af51bfdc4059de
|
||
Eric W. Biederman
|
ec5ef8d4d7 |
signal: Remove the bogus sigkill_pending in ptrace_stop
commit 7d613f9f72ec8f90ddefcae038fdae5adb8404b3 upstream. The existence of sigkill_pending is a little silly as it is functionally a duplicate of fatal_signal_pending that is used in exactly one place. Checking for pending fatal signals and returning early in ptrace_stop is actively harmful. It casues the ptrace_stop called by ptrace_signal to return early before setting current->exit_code. Later when ptrace_signal reads the signal number from current->exit_code is undefined, making it unpredictable what will happen. Instead rely on the fact that schedule will not sleep if there is a pending signal that can awaken a task. Removing the explict sigkill_pending test fixes fixes ptrace_signal when ptrace_stop does not stop because current->exit_code is always set to to signr. Cc: stable@vger.kernel.org Fixes: |
||
|
Greg Kroah-Hartman
|
0e161a13b1 |
This is the 5.4.76 stable release
-----BEGIN PGP SIGNATURE----- iQIzBAABCAAdFiEEZH8oZUiU471FcZm+ONu9yGCSaT4FAl+qe5YACgkQONu9yGCS aT6bAw//VGKqKOUOva6147u3U98FFBuYMJnZwZIxqvX4PFJnSwqKmsLUoCI8bhJV UJ+lbbBvyNbe2DS1+YkhlHTC15U7dHIWtSM4/FC7rvgTuvjAj4epqDDu5IkOoK4W Pil+zV1fwnwHrcuBbb5Ydk+mS3I/sVjObAQygluQPt1D2xESkyITq/uT9Lal0hRy fbyfUNYrhf4Bdeyfgzr7sEDrorgzQJ+7NBDR5NTzn0j0gph4hhe1z5FWmy8jEPXM kKy39nTrCu5hQhEL7L0G29ZLb0s8mhMM9B7OyKHCALtdc6VqwC3WFZqkwrr/cInQ bDuuBMngRe+n/A5xVMmsnjFyR+znXg82HYQuqrBJ1w3S4pbV+j0dcVJ9PiusyYdR n81HCakatyIq9Oe64yHKIlbxslkfgUjJX+uR4LfNS7iC4ad5fV/BwdCs0z0v2oOH o38e5V/qQFiI442+BR6fPagYEpHxJAlteZTpdUteYUBTpQ97v76K/10fqLdGc07s vevP4T2t3Z1qtswY5VbU2jOkNilgnOlqIw+VSzSXp4N8jcF+TEgtSB/X18eX69oy wQ8+aJzNjWCOFfqbYpS+1X2X/eVzBdBrQ8rk/FMKJ0Edxwm3YpoAqHb6copODzaZ cBwCyhbJbHeYpbzgJkkAJEZKffy6XWmwVqtYoi52HZNB1A5ipIA= =Cjfz -----END PGP SIGNATURE----- Merge 5.4.76 into android11-5.4-lts Changes in 5.4.76 drm/i915: Break up error capture compression loops with cond_resched() drm/i915/gt: Delay execlist processing for tgl drm/i915: Drop runtime-pm assert from vgpu io accessors ASoC: Intel: Skylake: Add alternative topology binary name linkage: Introduce new macros for assembler symbols arm64: asm: Add new-style position independent function annotations arm64: lib: Use modern annotations for assembly functions arm64: Change .weak to SYM_FUNC_START_WEAK_PI for arch/arm64/lib/mem*.S tipc: fix use-after-free in tipc_bcast_get_mode ptrace: fix task_join_group_stop() for the case when current is traced cadence: force nonlinear buffers to be cloned chelsio/chtls: fix memory leaks caused by a race chelsio/chtls: fix always leaking ctrl_skb gianfar: Replace skb_realloc_headroom with skb_cow_head for PTP gianfar: Account for Tx PTP timestamp in the skb headroom ionic: check port ptr before use ip_tunnel: fix over-mtu packet send fail without TUNNEL_DONT_FRAGMENT flags net: usb: qmi_wwan: add Telit LE910Cx 0x1230 composition powerpc/vnic: Extend "failover pending" window sctp: Fix COMM_LOST/CANT_STR_ASSOC err reporting on big-endian platforms sfp: Fix error handing in sfp_probe() Fonts: Replace discarded const qualifier ALSA: hda/realtek - Fixed HP headset Mic can't be detected ALSA: hda/realtek - Enable headphone for ASUS TM420 ALSA: usb-audio: Add implicit feedback quirk for Zoom UAC-2 ALSA: usb-audio: add usb vendor id as DSD-capable for Khadas devices ALSA: usb-audio: Add implicit feedback quirk for Qu-16 ALSA: usb-audio: Add implicit feedback quirk for MODX mm: mempolicy: fix potential pte_unmap_unlock pte error lib/crc32test: remove extra local_irq_disable/enable kthread_worker: prevent queuing delayed work from timer_fn when it is being canceled mm: always have io_remap_pfn_range() set pgprot_decrypted() gfs2: Wake up when sd_glock_disposal becomes zero ring-buffer: Fix recursion protection transitions between interrupt context mtd: spi-nor: Don't copy self-pointing struct around ftrace: Fix recursion check for NMI test ftrace: Handle tracing when switching between context regulator: defer probe when trying to get voltage from unresolved supply spi: bcm2835: fix gpio cs level inversion tracing: Fix out of bounds write in get_trace_buf futex: Handle transient "ownerless" rtmutex state correctly ARM: dts: sun4i-a10: fix cpu_alert temperature arm64: dts: meson: add missing g12 rng clock x86/kexec: Use up-to-dated screen_info copy to fill boot params of: Fix reserved-memory overlap detection drm/sun4i: frontend: Rework a bit the phase data drm/sun4i: frontend: Reuse the ch0 phase for RGB formats drm/sun4i: frontend: Fix the scaler phase on A33 blk-cgroup: Fix memleak on error path blk-cgroup: Pre-allocate tree node on blkg_conf_prep scsi: core: Don't start concurrent async scan on same host drm/amdgpu: add DID for navi10 blockchain SKU scsi: ibmvscsi: Fix potential race after loss of transport vsock: use ns_capable_noaudit() on socket create nvme-rdma: handle unexpected nvme completion data length nvmet: fix a NULL pointer dereference when tracing the flush command drm/vc4: drv: Add error handding for bind ACPI: NFIT: Fix comparison to '-ENXIO' usb: cdns3: gadget: suspicious implicit sign extension drm/nouveau/nouveau: fix the start/end range for migration drm/nouveau/gem: fix "refcount_t: underflow; use-after-free" arm64/smp: Move rcu_cpu_starting() earlier Revert "coresight: Make sysfs functional on topologies with per core sink" vt: Disable KD_FONT_OP_COPY fork: fix copy_process(CLONE_PARENT) race with the exiting ->real_parent s390/pkey: fix paes selftest failure with paes and pkey static build serial: 8250_mtk: Fix uart_get_baud_rate warning serial: txx9: add missing platform_driver_unregister() on error in serial_txx9_init USB: serial: cyberjack: fix write-URB completion race USB: serial: option: add Quectel EC200T module support USB: serial: option: add LE910Cx compositions 0x1203, 0x1230, 0x1231 USB: serial: option: add Telit FN980 composition 0x1055 tty: serial: fsl_lpuart: add LS1028A support tty: serial: fsl_lpuart: LS1021A has a FIFO size of 16 words, like LS1028A usb: dwc3: ep0: Fix delay status handling USB: Add NO_LPM quirk for Kingston flash drive usb: mtu3: fix panic in mtu3_gadget_stop() drm/panfrost: Fix a deadlock between the shrinker and madvise path ARC: stack unwinding: avoid indefinite looping PM: runtime: Drop runtime PM references to supplier on link removal PM: runtime: Drop pm_runtime_clean_up_links() PM: runtime: Resume the device earlier in __device_release_driver() xfs: flush for older, xfs specific ioctls perf/core: Fix a memory leak in perf_event_parse_addr_filter() arm64: dts: marvell: espressobin: Add ethernet switch aliases Linux 5.4.76 Signed-off-by: Greg Kroah-Hartman <gregkh@google.com> Change-Id: I9e122c9984f0a80613577d71e59101a97e92c1a4 |
||
Oleg Nesterov
|
1695fca8a9 |
ptrace: fix task_join_group_stop() for the case when current is traced
commit 7b3c36fc4c231ca532120bbc0df67a12f09c1d96 upstream.
This testcase
#include <stdio.h>
#include <unistd.h>
#include <signal.h>
#include <sys/ptrace.h>
#include <sys/wait.h>
#include <pthread.h>
#include <assert.h>
void *tf(void *arg)
{
return NULL;
}
int main(void)
{
int pid = fork();
if (!pid) {
kill(getpid(), SIGSTOP);
pthread_t th;
pthread_create(&th, NULL, tf, NULL);
return 0;
}
waitpid(pid, NULL, WSTOPPED);
ptrace(PTRACE_SEIZE, pid, 0, PTRACE_O_TRACECLONE);
waitpid(pid, NULL, 0);
ptrace(PTRACE_CONT, pid, 0,0);
waitpid(pid, NULL, 0);
int status;
int thread = waitpid(-1, &status, 0);
assert(thread > 0 && thread != pid);
assert(status == 0x80137f);
return 0;
}
fails and triggers WARN_ON_ONCE(!signr) in do_jobctl_trap().
This is because task_join_group_stop() has 2 problems when current is traced:
1. We can't rely on the "JOBCTL_STOP_PENDING" check, a stopped tracee
can be woken up by debugger and it can clone another thread which
should join the group-stop.
We need to check group_stop_count || SIGNAL_STOP_STOPPED.
2. If SIGNAL_STOP_STOPPED is already set, we should not increment
sig->group_stop_count and add JOBCTL_STOP_CONSUME. The new thread
should stop without another do_notify_parent_cldstop() report.
To clarify, the problem is very old and we should blame
ptrace_init_task(). But now that we have task_join_group_stop() it makes
more sense to fix this helper to avoid the code duplication.
Reported-by: syzbot+3485e3773f7da290eecc@syzkaller.appspotmail.com
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Christian Brauner <christian@brauner.io>
Cc: "Eric W . Biederman" <ebiederm@xmission.com>
Cc: Zhiqiang Liu <liuzhiqiang26@huawei.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: <stable@vger.kernel.org>
Link: https://lkml.kernel.org/r/20201019134237.GA18810@redhat.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
|
||
Abhilasha Rao
|
c283224524 |
ANDROID: GKI: signal: Export for __lock_task_sighand
- Add EXPORT_SYMBOL_GPL for __lock_task_sighand()
- This API is required by loadable driver module from samsung to
Lock task structure, when reading task/process related information.
Signed-off-by: Abhilasha Rao <abhilasha.hv@samsung.corp-partner.google.com>
Bug: 158067689
Change-Id: Ia54e17b1f2630bcc648e7840cf36e743f08ba9c9
(cherry picked from commit a719abf03114cfc0b9f68937d9cd900d74d65cae)
|
||
Zhiqiang Liu
|
16976275b9 |
signal: check sig before setting info in kill_pid_usb_asyncio
[ Upstream commit eaec2b0bd30690575c581eebffae64bfb7f684ac ] In kill_pid_usb_asyncio, if signal is not valid, we do not need to set info struct. Signed-off-by: Zhiqiang Liu <liuzhiqiang26@huawei.com> Acked-by: Christian Brauner <christian.brauner@ubuntu.com> Link: https://lore.kernel.org/r/f525fd08-1cf7-fb09-d20c-4359145eb940@huawei.com Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com> Signed-off-by: Sasha Levin <sashal@kernel.org> |
||
|
Eric W. Biederman
|
20821047ac |
signal: Avoid corrupting si_pid and si_uid in do_notify_parent
commit 61e713bdca3678e84815f2427f7a063fc353a1fc upstream. Christof Meerwald <cmeerw@cmeerw.org> writes: > Hi, > > this is probably related to commit > |
||
|
Eric W. Biederman
|
5f2d04139a |
signal: Extend exec_id to 64bits
commit d1e7fd6462ca9fc76650fbe6ca800e35b24267da upstream. Replace the 32bit exec_id with a 64bit exec_id to make it impossible to wrap the exec_id counter. With care an attacker can cause exec_id wrap and send arbitrary signals to a newly exec'd parent. This bypasses the signal sending checks if the parent changes their credentials during exec. The severity of this problem can been seen that in my limited testing of a 32bit exec_id it can take as little as 19s to exec 65536 times. Which means that it can take as little as 14 days to wrap a 32bit exec_id. Adam Zabrocki has succeeded wrapping the self_exe_id in 7 days. Even my slower timing is in the uptime of a typical server. Which means self_exec_id is simply a speed bump today, and if exec gets noticably faster self_exec_id won't even be a speed bump. Extending self_exec_id to 64bits introduces a problem on 32bit architectures where reading self_exec_id is no longer atomic and can take two read instructions. Which means that is is possible to hit a window where the read value of exec_id does not match the written value. So with very lucky timing after this change this still remains expoiltable. I have updated the update of exec_id on exec to use WRITE_ONCE and the read of exec_id in do_notify_parent to use READ_ONCE to make it clear that there is no locking between these two locations. Link: https://lore.kernel.org/kernel-hardening/20200324215049.GA3710@pi3.com.pl Fixes: 2.3.23pre2 Cc: stable@vger.kernel.org Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> |
||
|
Linus Torvalds
|
d1984c92f0 |
signal: avoid double atomic counter increments for user accounting
[ Upstream commit fda31c50292a5062332fa0343c084bd9f46604d9 ] When queueing a signal, we increment both the users count of pending signals (for RLIMIT_SIGPENDING tracking) and we increment the refcount of the user struct itself (because we keep a reference to the user in the signal structure in order to correctly account for it when freeing). That turns out to be fairly expensive, because both of them are atomic updates, and particularly under extreme signal handling pressure on big machines, you can get a lot of cache contention on the user struct. That can then cause horrid cacheline ping-pong when you do these multiple accesses. So change the reference counting to only pin the user for the _first_ pending signal, and to unpin it when the last pending signal is dequeued. That means that when a user sees a lot of concurrent signal queuing - which is the only situation when this matters - the only atomic access needed is generally the 'sigpending' count update. This was noticed because of a particularly odd timing artifact on a dual-socket 96C/192T Cascade Lake platform: when you get into bad contention, on that machine for some reason seems to be much worse when the contention happens in the upper 32-byte half of the cacheline. As a result, the kernel test robot will-it-scale 'signal1' benchmark had an odd performance regression simply due to random alignment of the 'struct user_struct' (and pointed to a completely unrelated and apparently nonsensical commit for the regression). Avoiding the double increments (and decrements on the dequeueing side, of course) makes for much less contention and hugely improved performance on that will-it-scale microbenchmark. Quoting Feng Tang: "It makes a big difference, that the performance score is tripled! bump from original 17000 to 54000. Also the gap between 5.0-rc6 and 5.0-rc6+Jiri's patch is reduced to around 2%" [ The "2% gap" is the odd cacheline placement difference on that platform: under the extreme contention case, the effect of which half of the cacheline was hot was 5%, so with the reduced contention the odd timing artifact is reduced too ] It does help in the non-contended case too, but is not nearly as noticeable. Reported-and-tested-by: Feng Tang <feng.tang@intel.com> Cc: Eric W. Biederman <ebiederm@xmission.com> Cc: Huang, Ying <ying.huang@intel.com> Cc: Philip Li <philip.li@intel.com> Cc: Andi Kleen <andi.kleen@intel.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org> |
||
|
Oleg Nesterov
|
937c6b27c7 |
cgroup: freezer: call cgroup_enter_frozen() with preemption disabled in ptrace_stop()
ptrace_stop() does preempt_enable_no_resched() to avoid the preemption,
but after that cgroup_enter_frozen() does spin_lock/unlock and this adds
another preemption point.
Reported-and-tested-by: Bruce Ashfield <bruce.ashfield@gmail.com>
Fixes:
|
||
|
Linus Torvalds
|
c17112a5c4 |
core-process-v5.4
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Merge tag 'core-process-v5.4' of git://git.kernel.org/pub/scm/linux/kernel/git/brauner/linux
Pull pidfd/waitid updates from Christian Brauner:
"This contains two features and various tests.
First, it adds support for waiting on process through pidfds by adding
the P_PIDFD type to the waitid() syscall. This completes the basic
functionality of the pidfd api (cf. [1]). In the meantime we also have
a new adition to the userspace projects that make use of the pidfd
api. The qt project was nice enough to send a mail pointing out that
they have a pr up to switch to the pidfd api (cf. [2]).
Second, this tag contains an extension to the waitid() syscall to make
it possible to wait on the current process group in a race free manner
(even though the actual problem is very unlikely) by specifing 0
together with the P_PGID type. This extension traces back to a
discussion on the glibc development mailing list.
There are also a range of tests for the features above. Additionally,
the test-suite which detected the pidfd-polling race we fixed in [3]
is included in this tag"
[1] https://lwn.net/Articles/794707/
[2] https://codereview.qt-project.org/c/qt/qtbase/+/108456
[3] commit
|
||
|
Eric W. Biederman
|
33da8e7c81 |
signal: Allow cifs and drbd to receive their terminating signals
My recent to change to only use force_sig for a synchronous events wound up breaking signal reception cifs and drbd. I had overlooked the fact that by default kthreads start out with all signals set to SIG_IGN. So a change I thought was safe turned out to have made it impossible for those kernel thread to catch their signals. Reverting the work on force_sig is a bad idea because what the code was doing was very much a misuse of force_sig. As the way force_sig ultimately allowed the signal to happen was to change the signal handler to SIG_DFL. Which after the first signal will allow userspace to send signals to these kernel threads. At least for wake_ack_receiver in drbd that does not appear actively wrong. So correct this problem by adding allow_kernel_signal that will allow signals whose siginfo reports they were sent by the kernel through, but will not allow userspace generated signals, and update cifs and drbd to call allow_kernel_signal in an appropriate place so that their thread can receive this signal. Fixing things this way ensures that userspace won't be able to send signals and cause problems, that it is clear which signals the threads are expecting to receive, and it guarantees that nothing else in the system will be affected. This change was partly inspired by similar cifs and drbd patches that added allow_signal. Reported-by: ronnie sahlberg <ronniesahlberg@gmail.com> Reported-by: Christoph Böhmwalder <christoph.boehmwalder@linbit.com> Tested-by: Christoph Böhmwalder <christoph.boehmwalder@linbit.com> Cc: Steve French <smfrench@gmail.com> Cc: Philipp Reisner <philipp.reisner@linbit.com> Cc: David Laight <David.Laight@ACULAB.COM> Fixes: |
||
Mauro Carvalho Chehab
|
68d8681e97 |
kernel/signal.c: fix a kernel-doc markup
The kernel-doc parser doesn't handle expressions with %foo*. Instead, when an asterisk should be part of a constant, it uses an alternative notation: `foo*`. Link: http://lkml.kernel.org/r/7f18c2e0b5e39e6b7eb55ddeb043b8b260b49f2d.1563361575.git.mchehab+samsung@kernel.org Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org> Cc: Deepa Dinamani <deepa.kernel@gmail.com> Cc: Jonathan Corbet <corbet@lwn.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
||
Christian Brauner
|
3695eae5fe
|
pidfd: add P_PIDFD to waitid()
This adds the P_PIDFD type to waitid(). One of the last remaining bits for the pidfd api is to make it possible to wait on pidfds. With P_PIDFD added to waitid() the parts of userspace that want to use the pidfd api to exclusively manage processes can do so now. One of the things this will unblock in the future is the ability to make it possible to retrieve the exit status via waitid(P_PIDFD) for non-parent processes if handed a _suitable_ pidfd that has this feature set. This is similar to what you can do on FreeBSD with kqueue(). It might even end up being possible to wait on a process as a non-parent if an appropriate property is enabled on the pidfd. With P_PIDFD no scoping of the process identified by the pidfd is possible, i.e. it explicitly blocks things such as wait4(-1), wait4(0), waitid(P_ALL), waitid(P_PGID) etc. It only allows for semantics equivalent to wait4(pid), waitid(P_PID). Users that need scoping should rely on pid-based wait*() syscalls for now. Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com> Reviewed-by: Kees Cook <keescook@chromium.org> Reviewed-by: Oleg Nesterov <oleg@redhat.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Cc: Joel Fernandes (Google) <joel@joelfernandes.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: David Howells <dhowells@redhat.com> Cc: Jann Horn <jannh@google.com> Cc: Andy Lutomirsky <luto@kernel.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Aleksa Sarai <cyphar@cyphar.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Al Viro <viro@zeniv.linux.org.uk> Link: https://lore.kernel.org/r/20190727222229.6516-2-christian@brauner.io |
||
Joel Fernandes (Google)
|
1caf7d50f4 |
pidfd: Add warning if exit_state is 0 during notification
Previously a condition got missed where the pidfd waiters are awakened before the exit_state gets set. This can result in a missed notification [1] and the polling thread waiting forever. It is fixed now, however it would be nice to avoid this kind of issue going unnoticed in the future. So just add a warning to catch it in the future. /* References */ [1]: https://lore.kernel.org/lkml/20190717172100.261204-1-joel@joelfernandes.org/ Signed-off-by: Joel Fernandes (Google) <joel@joelfernandes.org> Link: https://lore.kernel.org/r/20190724164816.201099-1-joel@joelfernandes.org Signed-off-by: Christian Brauner <christian@brauner.io> |
||
|
Oleg Nesterov
|
b772434be0 |
signal: simplify set_user_sigmask/restore_user_sigmask
task->saved_sigmask and ->restore_sigmask are only used in the ret-from- syscall paths. This means that set_user_sigmask() can save ->blocked in ->saved_sigmask and do set_restore_sigmask() to indicate that ->blocked was modified. This way the callers do not need 2 sigset_t's passed to set/restore and restore_user_sigmask() renamed to restore_saved_sigmask_unless() turns into the trivial helper which just calls restore_saved_sigmask(). Link: http://lkml.kernel.org/r/20190606113206.GA9464@redhat.com Signed-off-by: Oleg Nesterov <oleg@redhat.com> Cc: Deepa Dinamani <deepa.kernel@gmail.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Jens Axboe <axboe@kernel.dk> Cc: Davidlohr Bueso <dave@stgolabs.net> Cc: Eric Wong <e@80x24.org> Cc: Jason Baron <jbaron@akamai.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Al Viro <viro@ZenIV.linux.org.uk> Cc: Eric W. Biederman <ebiederm@xmission.com> Cc: David Laight <David.Laight@aculab.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
||
|
Linus Torvalds
|
5450e8a316 |
pidfd-updates-v5.3
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Merge tag 'pidfd-updates-v5.3' of git://git.kernel.org/pub/scm/linux/kernel/git/brauner/linux
Pull pidfd updates from Christian Brauner:
"This adds two main features.
- First, it adds polling support for pidfds. This allows process
managers to know when a (non-parent) process dies in a race-free
way.
The notification mechanism used follows the same logic that is
currently used when the parent of a task is notified of a child's
death. With this patchset it is possible to put pidfds in an
{e}poll loop and get reliable notifications for process (i.e.
thread-group) exit.
- The second feature compliments the first one by making it possible
to retrieve pollable pidfds for processes that were not created
using CLONE_PIDFD.
A lot of processes get created with traditional PID-based calls
such as fork() or clone() (without CLONE_PIDFD). For these
processes a caller can currently not create a pollable pidfd. This
is a problem for Android's low memory killer (LMK) and service
managers such as systemd.
Both patchsets are accompanied by selftests.
It's perhaps worth noting that the work done so far and the work done
in this branch for pidfd_open() and polling support do already see
some adoption:
- Android is in the process of backporting this work to all their LTS
kernels [1]
- Service managers make use of pidfd_send_signal but will need to
wait until we enable waiting on pidfds for full adoption.
- And projects I maintain make use of both pidfd_send_signal and
CLONE_PIDFD [2] and will use polling support and pidfd_open() too"
[1] https://android-review.googlesource.com/q/topic:%22pidfd+polling+support+4.9+backport%22
https://android-review.googlesource.com/q/topic:%22pidfd+polling+support+4.14+backport%22
https://android-review.googlesource.com/q/topic:%22pidfd+polling+support+4.19+backport%22
[2]
|
||
|
Linus Torvalds
|
5ad18b2e60 |
Merge branch 'siginfo-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace
Pull force_sig() argument change from Eric Biederman: "A source of error over the years has been that force_sig has taken a task parameter when it is only safe to use force_sig with the current task. The force_sig function is built for delivering synchronous signals such as SIGSEGV where the userspace application caused a synchronous fault (such as a page fault) and the kernel responded with a signal. Because the name force_sig does not make this clear, and because the force_sig takes a task parameter the function force_sig has been abused for sending other kinds of signals over the years. Slowly those have been fixed when the oopses have been tracked down. This set of changes fixes the remaining abusers of force_sig and carefully rips out the task parameter from force_sig and friends making this kind of error almost impossible in the future" * 'siginfo-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace: (27 commits) signal/x86: Move tsk inside of CONFIG_MEMORY_FAILURE in do_sigbus signal: Remove the signal number and task parameters from force_sig_info signal: Factor force_sig_info_to_task out of force_sig_info signal: Generate the siginfo in force_sig signal: Move the computation of force into send_signal and correct it. signal: Properly set TRACE_SIGNAL_LOSE_INFO in __send_signal signal: Remove the task parameter from force_sig_fault signal: Use force_sig_fault_to_task for the two calls that don't deliver to current signal: Explicitly call force_sig_fault on current signal/unicore32: Remove tsk parameter from __do_user_fault signal/arm: Remove tsk parameter from __do_user_fault signal/arm: Remove tsk parameter from ptrace_break signal/nds32: Remove tsk parameter from send_sigtrap signal/riscv: Remove tsk parameter from do_trap signal/sh: Remove tsk parameter from force_sig_info_fault signal/um: Remove task parameter from send_sigtrap signal/x86: Remove task parameter from send_sigtrap signal: Remove task parameter from force_sig_mceerr signal: Remove task parameter from force_sig signal: Remove task parameter from force_sigsegv ... |
||
|
Linus Torvalds
|
61fc5771f5 |
audit/stable-5.3 PR 20190702
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Merge tag 'audit-pr-20190702' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/audit
Pull audit updates from Paul Moore:
"This pull request is a bit early, but with some vacation time coming
up I wanted to send this out now just in case the remote Internet Gods
decide not to smile on me once the merge window opens. The patchset
for v5.3 is pretty minor this time, the highlights include:
- When the audit daemon is sent a signal, ensure we deliver
information about the sender even when syscall auditing is not
enabled/supported.
- Add the ability to filter audit records based on network address
family.
- Tighten the audit field filtering restrictions on string based
fields.
- Cleanup the audit field filtering verification code.
- Remove a few BUG() calls from the audit code"
* tag 'audit-pr-20190702' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/audit:
audit: remove the BUG() calls in the audit rule comparison functions
audit: enforce op for string fields
audit: add saddr_fam filter field
audit: re-structure audit field valid checks
audit: deliver signal_info regarless of syscall
|
||
|
Oleg Nesterov
|
97abc889ee |
signal: remove the wrong signal_pending() check in restore_user_sigmask()
This is the minimal fix for stable, I'll send cleanups later. Commit |
||
|
Joel Fernandes (Google)
|
b53b0b9d9a
|
pidfd: add polling support
This patch adds polling support to pidfd. Android low memory killer (LMK) needs to know when a process dies once it is sent the kill signal. It does so by checking for the existence of /proc/pid which is both racy and slow. For example, if a PID is reused between when LMK sends a kill signal and checks for existence of the PID, since the wrong PID is now possibly checked for existence. Using the polling support, LMK will be able to get notified when a process exists in race-free and fast way, and allows the LMK to do other things (such as by polling on other fds) while awaiting the process being killed to die. For notification to polling processes, we follow the same existing mechanism in the kernel used when the parent of the task group is to be notified of a child's death (do_notify_parent). This is precisely when the tasks waiting on a poll of pidfd are also awakened in this patch. We have decided to include the waitqueue in struct pid for the following reasons: 1. The wait queue has to survive for the lifetime of the poll. Including it in task_struct would not be option in this case because the task can be reaped and destroyed before the poll returns. 2. By including the struct pid for the waitqueue means that during de_thread(), the new thread group leader automatically gets the new waitqueue/pid even though its task_struct is different. Appropriate test cases are added in the second patch to provide coverage of all the cases the patch is handling. Cc: Andy Lutomirski <luto@amacapital.net> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Daniel Colascione <dancol@google.com> Cc: Jann Horn <jannh@google.com> Cc: Tim Murray <timmurray@google.com> Cc: Jonathan Kowalski <bl0pbl33p@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Kees Cook <keescook@chromium.org> Cc: David Howells <dhowells@redhat.com> Cc: Oleg Nesterov <oleg@redhat.com> Cc: kernel-team@android.com Reviewed-by: Oleg Nesterov <oleg@redhat.com> Co-developed-by: Daniel Colascione <dancol@google.com> Signed-off-by: Daniel Colascione <dancol@google.com> Signed-off-by: Joel Fernandes (Google) <joel@joelfernandes.org> Signed-off-by: Christian Brauner <christian@brauner.io> |
||
Christian Brauner
|
c732327f04
|
signal: improve comments
Improve the comments for pidfd_send_signal(). First, the comment still referred to a file descriptor for a process as a "task file descriptor" which stems from way back at the beginning of the discussion. Replace this with "pidfd" for consistency. Second, the wording for the explanation of the arguments to the syscall was a bit inconsistent, e.g. some used the past tense some used present tense. Make the wording more consistent. Signed-off-by: Christian Brauner <christian@brauner.io> |
||
Zhenliang Wei
|
98af37d624 |
kernel/signal.c: trace_signal_deliver when signal_group_exit
In the fixes commit, removing SIGKILL from each thread signal mask and
executing "goto fatal" directly will skip the call to
"trace_signal_deliver". At this point, the delivery tracking of the
SIGKILL signal will be inaccurate.
Therefore, we need to add trace_signal_deliver before "goto fatal" after
executing sigdelset.
Note: SEND_SIG_NOINFO matches the fact that SIGKILL doesn't have any info.
Link: http://lkml.kernel.org/r/20190425025812.91424-1-weizhenliang@huawei.com
Fixes:
|
||
|
Eric W. Biederman
|
a89e9b8abf |
signal: Remove the signal number and task parameters from force_sig_info
force_sig_info always delivers to the current task and the signal parameter always matches info.si_signo. So remove those parameters to make it a simpler less error prone interface, and to make it clear that none of the callers are doing anything clever. This guarantees that force_sig_info will not grow any new buggy callers that attempt to call force_sig on a non-current task, or that pass an signal number that does not match info.si_signo. Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> |
||
|
Eric W. Biederman
|
59c0e696a6 |
signal: Factor force_sig_info_to_task out of force_sig_info
All callers of force_sig_info pass info.si_signo in for the signal by definition as well as in practice. Further all callers of force_sig_info except force_sig_fault_to_task pass current as the target task to force_sig_info. Factor out a static force_sig_info_to_task that force_sig_fault_to_task can call. This prepares the way for force_sig_info to have it's task and signal parameters removed. Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> |
||
|
Eric W. Biederman
|
ffafd23b2c |
signal: Generate the siginfo in force_sig
In preparation for removing the special case in force_sig_info for only having a signal number generate an appropriate siginfo in force_sig the last caller of force_sig_info that does not pass a filled out siginfo. Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> |
||
|
Eric W. Biederman
|
8ad23dea80 |
signal: Move the computation of force into send_signal and correct it.
Forcing a signal or not allowing a pid namespace init to ignore SIGKILL or SIGSTOP is more cleanly computed in send_signal. There are two cases where we don't allow a pid namespace init to ignore SIGKILL or SIGSTOP. If the sending process is from an ancestor pid namespace and as such is effectively the god to the target process, and if the it is the kernel that is sending the signal, not another application. It is known that a process is from an ancestor pid namespace if it can see it's target but it's target does not have a pid for the sender in it's pid namespace. It is know that a signal is sent from the kernel if si_code is set to SI_KERNEL or info is SEND_SIG_PRIV (which ultimately generates a signal with si_code == SI_KERNEL). The only signals that matter are SIGKILL and SIGSTOP neither of which can really be caught, and both of which always have a siginfo layout that includes si_uid and si_pid. Therefore we never need to worry about forcing a signal when si_pid and si_uid are absent. So handle the two special cases of info and the case when si_pid and si_uid are present. Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> |
||
|
Eric W. Biederman
|
8917bef336 |
signal: Properly set TRACE_SIGNAL_LOSE_INFO in __send_signal
Any time siginfo is not stored in the signal queue information is
lost. Therefore set TRACE_SIGNAL_LOSE_INFO every time the code does
not allocate a signal queue entry, and a queue overflow abort is not
triggered.
Fixes:
|
||
|
Eric W. Biederman
|
2e1661d267 |
signal: Remove the task parameter from force_sig_fault
As synchronous exceptions really only make sense against the current task (otherwise how are you synchronous) remove the task parameter from from force_sig_fault to make it explicit that is what is going on. The two known exceptions that deliver a synchronous exception to a stopped ptraced task have already been changed to force_sig_fault_to_task. The callers have been changed with the following emacs regular expression (with obvious variations on the architectures that take more arguments) to avoid typos: force_sig_fault[(]\([^,]+\)[,]\([^,]+\)[,]\([^,]+\)[,]\W+current[)] -> force_sig_fault(\1,\2,\3) Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> |
||
|
Eric W. Biederman
|
91ca180dbd |
signal: Use force_sig_fault_to_task for the two calls that don't deliver to current
In preparation for removing the task parameter from force_sig_fault introduce force_sig_fault_to_task and use it for the two cases where it matters. On mips force_fcr31_sig calls force_sig_fault and is called on either the current task, or a task that is suspended and is being switched to by the scheduler. This is safe because the task being switched to by the scheduler is guaranteed to be suspended. This ensures that task->sighand is stable while the signal is delivered to it. On parisc user_enable_single_step calls force_sig_fault and is in turn called by ptrace_request. The function ptrace_request always calls user_enable_single_step on a child that is stopped for tracing. The child being traced and not reaped ensures that child->sighand is not NULL, and that the child will not change child->sighand. Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> |
||
|
Eric W. Biederman
|
f8eac9011b |
signal: Remove task parameter from force_sig_mceerr
All of the callers pass current into force_sig_mceer so remove the task parameter to make this obvious. This also makes it clear that force_sig_mceerr passes current into force_sig_info. Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> |
||
|
Eric W. Biederman
|
3cf5d076fb |
signal: Remove task parameter from force_sig
All of the remaining callers pass current into force_sig so remove the task parameter to make this obvious and to make misuse more difficult in the future. This also makes it clear force_sig passes current into force_sig_info. Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> |
||
|
Eric W. Biederman
|
cb44c9a0ab |
signal: Remove task parameter from force_sigsegv
The function force_sigsegv is always called on the current task so passing in current is redundant and not passing in current makes this fact obvious. This also makes it clear force_sigsegv always calls force_sig on the current task. Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> |
||
|
Eric W. Biederman
|
7a0cf09494 |
signal: Correct namespace fixups of si_pid and si_uid
The function send_signal was split from __send_signal so that it would be possible to bypass the namespace logic based upon current[1]. As it turns out the si_pid and the si_uid fixup are both inappropriate in the case of kill_pid_usb_asyncio so move that logic into send_signal. It is difficult to arrange but possible for a signal with an si_code of SI_TIMER or SI_SIGIO to be sent across namespace boundaries. In which case tests for when it is ok to change si_pid and si_uid based on SI_FROMUSER are incorrect. Replace the use of SI_FROMUSER with a new test has_si_pid_and_used based on siginfo_layout. Now that the uid fixup is no longer present after expanding SEND_SIG_NOINFO properly calculate the si_uid that the target task needs to read. [1] |
||
|
Eric W. Biederman
|
70f1b0d34b |
signal/usb: Replace kill_pid_info_as_cred with kill_pid_usb_asyncio
The usb support for asyncio encoded one of it's values in the wrong
field. It should have used si_value but instead used si_addr which is
not present in the _rt union member of struct siginfo.
The practical result of this is that on a 64bit big endian kernel
when delivering a signal to a 32bit process the si_addr field
is set to NULL, instead of the expected pointer value.
This issue can not be fixed in copy_siginfo_to_user32 as the usb
usage of the the _sigfault (aka si_addr) member of the siginfo
union when SI_ASYNCIO is set is incompatible with the POSIX and
glibc usage of the _rt member of the siginfo union.
Therefore replace kill_pid_info_as_cred with kill_pid_usb_asyncio a
dedicated function for this one specific case. There are no other
users of kill_pid_info_as_cred so this specialization should have no
impact on the amount of code in the kernel. Have kill_pid_usb_asyncio
take instead of a siginfo_t which is difficult and error prone, 3
arguments, a signal number, an errno value, and an address enconded as
a sigval_t. The encoding of the address as a sigval_t allows the
code that reads the userspace request for a signal to handle this
compat issue along with all of the other compat issues.
Add BUILD_BUG_ONs in kernel/signal.c to ensure that we can now place
the pointer value at the in si_pid (instead of si_addr). That is the
code now verifies that si_pid and si_addr always occur at the same
location. Further the code veries that for native structures a value
placed in si_pid and spilling into si_uid will appear in userspace in
si_addr (on a byte by byte copy of siginfo or a field by field copy of
siginfo). The code also verifies that for a 64bit kernel and a 32bit
userspace the 32bit pointer will fit in si_pid.
I have used the usbsig.c program below written by Alan Stern and
slightly tweaked by me to run on a big endian machine to verify the
issue exists (on sparc64) and to confirm the patch below fixes the issue.
/* usbsig.c -- test USB async signal delivery */
#define _GNU_SOURCE
#include <stdio.h>
#include <fcntl.h>
#include <signal.h>
#include <string.h>
#include <sys/ioctl.h>
#include <unistd.h>
#include <endian.h>
#include <linux/usb/ch9.h>
#include <linux/usbdevice_fs.h>
static struct usbdevfs_urb urb;
static struct usbdevfs_disconnectsignal ds;
static volatile sig_atomic_t done = 0;
void urb_handler(int sig, siginfo_t *info , void *ucontext)
{
printf("Got signal %d, signo %d errno %d code %d addr: %p urb: %p\n",
sig, info->si_signo, info->si_errno, info->si_code,
info->si_addr, &urb);
printf("%s\n", (info->si_addr == &urb) ? "Good" : "Bad");
}
void ds_handler(int sig, siginfo_t *info , void *ucontext)
{
printf("Got signal %d, signo %d errno %d code %d addr: %p ds: %p\n",
sig, info->si_signo, info->si_errno, info->si_code,
info->si_addr, &ds);
printf("%s\n", (info->si_addr == &ds) ? "Good" : "Bad");
done = 1;
}
int main(int argc, char **argv)
{
char *devfilename;
int fd;
int rc;
struct sigaction act;
struct usb_ctrlrequest *req;
void *ptr;
char buf[80];
if (argc != 2) {
fprintf(stderr, "Usage: usbsig device-file-name\n");
return 1;
}
devfilename = argv[1];
fd = open(devfilename, O_RDWR);
if (fd == -1) {
perror("Error opening device file");
return 1;
}
act.sa_sigaction = urb_handler;
sigemptyset(&act.sa_mask);
act.sa_flags = SA_SIGINFO;
rc = sigaction(SIGUSR1, &act, NULL);
if (rc == -1) {
perror("Error in sigaction");
return 1;
}
act.sa_sigaction = ds_handler;
sigemptyset(&act.sa_mask);
act.sa_flags = SA_SIGINFO;
rc = sigaction(SIGUSR2, &act, NULL);
if (rc == -1) {
perror("Error in sigaction");
return 1;
}
memset(&urb, 0, sizeof(urb));
urb.type = USBDEVFS_URB_TYPE_CONTROL;
urb.endpoint = USB_DIR_IN | 0;
urb.buffer = buf;
urb.buffer_length = sizeof(buf);
urb.signr = SIGUSR1;
req = (struct usb_ctrlrequest *) buf;
req->bRequestType = USB_DIR_IN | USB_TYPE_STANDARD | USB_RECIP_DEVICE;
req->bRequest = USB_REQ_GET_DESCRIPTOR;
req->wValue = htole16(USB_DT_DEVICE << 8);
req->wIndex = htole16(0);
req->wLength = htole16(sizeof(buf) - sizeof(*req));
rc = ioctl(fd, USBDEVFS_SUBMITURB, &urb);
if (rc == -1) {
perror("Error in SUBMITURB ioctl");
return 1;
}
rc = ioctl(fd, USBDEVFS_REAPURB, &ptr);
if (rc == -1) {
perror("Error in REAPURB ioctl");
return 1;
}
memset(&ds, 0, sizeof(ds));
ds.signr = SIGUSR2;
ds.context = &ds;
rc = ioctl(fd, USBDEVFS_DISCSIGNAL, &ds);
if (rc == -1) {
perror("Error in DISCSIGNAL ioctl");
return 1;
}
printf("Waiting for usb disconnect\n");
while (!done) {
sleep(1);
}
close(fd);
return 0;
}
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: linux-usb@vger.kernel.org
Cc: Alan Stern <stern@rowland.harvard.edu>
Cc: Oliver Neukum <oneukum@suse.com>
Fixes: v2.3.39
Cc: stable@vger.kernel.org
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
|
||
Richard Guy Briggs
|
b48345aafb |
audit: deliver signal_info regarless of syscall
When a process signals the audit daemon (shutdown, rotate, resume, reconfig) but syscall auditing is not enabled, we still want to know the identity of the process sending the signal to the audit daemon. Move audit_signal_info() out of syscall auditing to general auditing but create a new function audit_signal_info_syscall() to take care of the syscall dependent parts for when syscall auditing is enabled. Please see the github kernel audit issue https://github.com/linux-audit/audit-kernel/issues/111 Signed-off-by: Richard Guy Briggs <rgb@redhat.com> Signed-off-by: Paul Moore <paul@paul-moore.com> |
||
Thomas Gleixner
|
457c899653 |
treewide: Add SPDX license identifier for missed files
Add SPDX license identifiers to all files which: - Have no license information of any form - Have EXPORT_.*_SYMBOL_GPL inside which was used in the initial scan/conversion to ignore the file These files fall under the project license, GPL v2 only. The resulting SPDX license identifier is: GPL-2.0-only Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> |
||
Roman Gushchin
|
05b2892637 |
signal: unconditionally leave the frozen state in ptrace_stop()
Alex Xu reported a regression in strace, caused by the introduction of
the cgroup v2 freezer. The regression can be reproduced by stracing
the following simple program:
#include <unistd.h>
int main() {
write(1, "a", 1);
return 0;
}
An attempt to run strace ./a.out leads to the infinite loop:
[ pre-main omitted ]
write(1, "a", 1) = ? ERESTARTSYS (To be restarted if SA_RESTART is set)
write(1, "a", 1) = ? ERESTARTSYS (To be restarted if SA_RESTART is set)
write(1, "a", 1) = ? ERESTARTSYS (To be restarted if SA_RESTART is set)
write(1, "a", 1) = ? ERESTARTSYS (To be restarted if SA_RESTART is set)
write(1, "a", 1) = ? ERESTARTSYS (To be restarted if SA_RESTART is set)
write(1, "a", 1) = ? ERESTARTSYS (To be restarted if SA_RESTART is set)
[ repeats forever ]
The problem occurs because the traced task leaves ptrace_stop()
(and the signal handling loop) with the frozen bit set. So let's
call cgroup_leave_frozen(true) unconditionally after sleeping
in ptrace_stop().
With this patch applied, strace works as expected:
[ pre-main omitted ]
write(1, "a", 1) = 1
exit_group(0) = ?
+++ exited with 0 +++
Reported-by: Alex Xu <alex_y_xu@yahoo.ca>
Fixes:
|
||
Mathieu Malaterre
|
b028fb6128 |
kernel/signal.c: annotate implicit fall through
There is a plan to build the kernel with -Wimplicit-fallthrough and this place in the code produced a warning (W=1). This commit remove the following warning: kernel/signal.c:795:13: warning: this statement may fall through [-Wimplicit-fallthrough=] Link: http://lkml.kernel.org/r/20190114203505.17875-1-malat@debian.org Signed-off-by: Mathieu Malaterre <malat@debian.org> Acked-by: Gustavo A. R. Silva <gustavo@embeddedor.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
||
|
Linus Torvalds
|
abde77eb5c |
Merge branch 'for-5.2' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup
Pull cgroup updates from Tejun Heo: "This includes Roman's cgroup2 freezer implementation. It's a separate machanism from cgroup1 freezer. Instead of blocking user tasks in arbitrary uninterruptible sleeps, the new implementation extends jobctl stop - frozen tasks are trapped in jobctl stop until thawed and can be killed and ptraced. Lots of thanks to Oleg for sheperding the effort. Other than that, there are a few trivial changes" * 'for-5.2' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup: cgroup: never call do_group_exit() with task->frozen bit set kernel: cgroup: fix misuse of %x cgroup: get rid of cgroup_freezer_frozen_exit() cgroup: prevent spurious transition into non-frozen state cgroup: Remove unused cgrp variable cgroup: document cgroup v2 freezer interface cgroup: add tracing points for cgroup v2 freezer cgroup: make TRACE_CGROUP_PATH irq-safe kselftests: cgroup: add freezer controller self-tests kselftests: cgroup: don't fail on cg_kill_all() error in cg_destroy() cgroup: cgroup v2 freezer cgroup: protect cgroup->nr_(dying_)descendants by css_set_lock cgroup: implement __cgroup_task_count() helper cgroup: rename freezer.c into legacy_freezer.c cgroup: remove extra cgroup_migrate_finish() call |
||
|
Roman Gushchin
|
f2b31bb598 |
cgroup: never call do_group_exit() with task->frozen bit set
I've got two independent reports that cgroup_task_frozen() check in cgroup_exit() has been triggered by lkp libhugetlbfs-test and LTP ptrace01 tests. For example: [ 44.576072] WARNING: CPU: 1 PID: 3028 at kernel/cgroup/cgroup.c:5932 cgroup_exit+0x148/0x160 [ 44.577724] Modules linked in: crct10dif_pclmul crc32_pclmul crc32c_intel ghash_clmulni_intel sr_mod cdrom bochs_drm sg ttm ata_generic pata_acpi ppdev drm_kms_helper snd_pcm syscopyarea aesni_intel snd_timer sysfillrect sysimgblt snd crypto_simd cryptd glue_helper soundcore fb_sys_fops joydev drm serio_raw pcspkr ata_piix libata i2c_piix4 floppy parport_pc parport ip_tables [ 44.583106] CPU: 1 PID: 3028 Comm: ptrace-write-hu Not tainted 5.1.0-rc3-00053-g9262503 #5 [ 44.584600] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-1 04/01/2014 [ 44.586116] RIP: 0010:cgroup_exit+0x148/0x160 [ 44.587135] Code: 0f 84 50 ff ff ff 48 8b 85 c8 0c 00 00 48 8b 78 70 e8 ec 2e 00 00 e9 3b ff ff ff f0 ff 43 60 0f 88 72 21 89 00 e9 48 ff ff ff <0f> 0b e9 1b ff ff ff e8 3c 73 f4 ff 66 90 66 2e 0f 1f 84 00 00 00 [ 44.590113] RSP: 0018:ffffb25702dcfd30 EFLAGS: 00010002 [ 44.591167] RAX: ffff96a7fee32410 RBX: ffff96a7ff1d6000 RCX: dead000000000200 [ 44.592446] RDX: ffff96a7ff1d6080 RSI: ffff96a7fec75290 RDI: ffff96a7fec75290 [ 44.593715] RBP: ffff96a7fec745c0 R08: ffff96a7fec74658 R09: 0000000000000000 [ 44.594985] R10: 0000000000000000 R11: 0000000000000001 R12: ffff96a7fec75101 [ 44.596266] R13: ffff96a7fec745c0 R14: ffff96a7ff3bde30 R15: ffff96a7fec75130 [ 44.597550] FS: 0000000000000000(0000) GS:ffff96a7dd700000(0000) knlGS:0000000000000000 [ 44.598950] CS: 0010 DS: 002b ES: 002b CR0: 0000000080050033 [ 44.600098] CR2: 00000000f7a00000 CR3: 000000000d20e000 CR4: 00000000000406e0 [ 44.601417] Call Trace: [ 44.602777] do_exit+0x337/0xc40 [ 44.603677] do_group_exit+0x3a/0xa0 [ 44.604610] get_signal+0x12e/0x8d0 [ 44.605533] ? __switch_to_asm+0x40/0x70 [ 44.606503] do_signal+0x36/0x650 [ 44.607409] ? __switch_to_asm+0x40/0x70 [ 44.608383] ? __schedule+0x267/0x860 [ 44.609329] exit_to_usermode_loop+0x89/0xf0 [ 44.610349] do_fast_syscall_32+0x251/0x2e3 [ 44.611357] entry_SYSENTER_compat+0x7f/0x91 [ 44.612376] ---[ end trace e4ca5cfc4b7f7964 ]--- The problem is caused by the ptrace_signal() call in the for loop in get_signal(). There is a cgroup_enter_frozen() call inside ptrace_signal(), so after exit from ptrace_signal() the task->frozen bit might be set. In this case do_group_exit() can be called with the task->frozen bit set and trigger the warning. This is only place where we can leave the loop with the task->frozen bit set and without setting JOBCTL_TRAP_FREEZE and TIF_SIGPENDING. To resolve this problem, let's move cgroup_leave_frozen(true) call to just after the fatal label. If the task is going to die, the frozen bit must be cleared no matter how we get into this point. Reported-by: kernel test robot <rong.a.chen@intel.com> Reported-by: Qian Cai <cai@lca.pw> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Tejun Heo <tj@kernel.org> Signed-off-by: Roman Gushchin <guro@fb.com> Signed-off-by: Tejun Heo <tj@kernel.org> |
||
|
Linus Torvalds
|
eac7078a0f |
pidfd patches for v5.2-rc1
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||
|
Christian Brauner
|
2151ad1b06
|
signal: support CLONE_PIDFD with pidfd_send_signal
Let pidfd_send_signal() use pidfds retrieved via CLONE_PIDFD. With this patch pidfd_send_signal() becomes independent of procfs. This fullfils the request made when we merged the pidfd_send_signal() patchset. The pidfd_send_signal() syscall is now always available allowing for it to be used by users without procfs mounted or even users without procfs support compiled into the kernel. Signed-off-by: Christian Brauner <christian@brauner.io> Co-developed-by: Jann Horn <jannh@google.com> Signed-off-by: Jann Horn <jannh@google.com> Acked-by: Oleg Nesterov <oleg@redhat.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Cc: Kees Cook <keescook@chromium.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: David Howells <dhowells@redhat.com> Cc: "Michael Kerrisk (man-pages)" <mtk.manpages@gmail.com> Cc: Andy Lutomirsky <luto@kernel.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Aleksa Sarai <cyphar@cyphar.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Al Viro <viro@zeniv.linux.org.uk> |
||
|
Roman Gushchin
|
cb2c4cd878 |
cgroup: prevent spurious transition into non-frozen state
If freezing of a cgroup races with waking of a task from the frozen state (like waiting in vfork() or in do_signal_stop()), a spurious transition of the cgroup state can happen. The task enters cgroup_leave_frozen(true), the cgroup->nr_frozen_tasks counter decrements, and the cgroup is switched to the unfrozen state. To prevent it, let's reserve cgroup_leave_frozen(true) for terminating processes and use cgroup_leave_frozen(false) otherwise. To avoid busy-looping in the signal handling loop waiting for JOBCTL_TRAP_FREEZE set from the cgroup freezing path, let's do it explicitly in cgroup_leave_frozen(), if the task is going to stay frozen. Suggested-by: Oleg Nesterov <oleg@redhat.com> Signed-off-by: Roman Gushchin <guro@fb.com> Signed-off-by: Tejun Heo <tj@kernel.org> |
||
|
Roman Gushchin
|
76f969e894 |
cgroup: cgroup v2 freezer
Cgroup v1 implements the freezer controller, which provides an ability
to stop the workload in a cgroup and temporarily free up some
resources (cpu, io, network bandwidth and, potentially, memory)
for some other tasks. Cgroup v2 lacks this functionality.
This patch implements freezer for cgroup v2.
Cgroup v2 freezer tries to put tasks into a state similar to jobctl
stop. This means that tasks can be killed, ptraced (using
PTRACE_SEIZE*), and interrupted. It is possible to attach to
a frozen task, get some information (e.g. read registers) and detach.
It's also possible to migrate a frozen tasks to another cgroup.
This differs cgroup v2 freezer from cgroup v1 freezer, which mostly
tried to imitate the system-wide freezer. However uninterruptible
sleep is fine when all tasks are going to be frozen (hibernation case),
it's not the acceptable state for some subset of the system.
Cgroup v2 freezer is not supporting freezing kthreads.
If a non-root cgroup contains kthread, the cgroup still can be frozen,
but the kthread will remain running, the cgroup will be shown
as non-frozen, and the notification will not be delivered.
* PTRACE_ATTACH is not working because non-fatal signal delivery
is blocked in frozen state.
There are some interface differences between cgroup v1 and cgroup v2
freezer too, which are required to conform the cgroup v2 interface
design principles:
1) There is no separate controller, which has to be turned on:
the functionality is always available and is represented by
cgroup.freeze and cgroup.events cgroup control files.
2) The desired state is defined by the cgroup.freeze control file.
Any hierarchical configuration is allowed.
3) The interface is asynchronous. The actual state is available
using cgroup.events control file ("frozen" field). There are no
dedicated transitional states.
4) It's allowed to make any changes with the cgroup hierarchy
(create new cgroups, remove old cgroups, move tasks between cgroups)
no matter if some cgroups are frozen.
Signed-off-by: Roman Gushchin <guro@fb.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
No-objection-from-me-by: Oleg Nesterov <oleg@redhat.com>
Cc: kernel-team@fb.com
|
||
|
Christian Brauner
|
738a7832d2 |
signal: use fdget() since we don't allow O_PATH
As stated in the original commit for pidfd_send_signal() we don't allow to signal processes through O_PATH file descriptors since it is semantically equivalent to a write on the pidfd. We already correctly error out right now and return EBADF if an O_PATH fd is passed. This is because we use file->f_op to detect whether a pidfd is passed and O_PATH fds have their file->f_op set to empty_fops in do_dentry_open() and thus fail the test. Thus, there is no regression. It's just semantically correct to use fdget() and return an error right from there instead of taking a reference and returning an error later. Signed-off-by: Christian Brauner <christian@brauner.io> Acked-by: Oleg Nesterov <oleg@redhat.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Cc: Kees Cook <keescook@chromium.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Jann Horn <jann@thejh.net> Cc: David Howells <dhowells@redhat.com> Cc: "Michael Kerrisk (man-pages)" <mtk.manpages@gmail.com> Cc: Andy Lutomirsky <luto@kernel.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Aleksa Sarai <cyphar@cyphar.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
||
Jann Horn
|
556a888a14
|
signal: don't silently convert SI_USER signals to non-current pidfd
The current sys_pidfd_send_signal() silently turns signals with explicit
SI_USER context that are sent to non-current tasks into signals with
kernel-generated siginfo.
This is unlike do_rt_sigqueueinfo(), which returns -EPERM in this case.
If a user actually wants to send a signal with kernel-provided siginfo,
they can do that with pidfd_send_signal(pidfd, sig, NULL, 0); so allowing
this case is unnecessary.
Instead of silently replacing the siginfo, just bail out with an error;
this is consistent with other interfaces and avoids special-casing behavior
based on security checks.
Fixes:
|
||
|
Linus Torvalds
|
a9dce6679d |
pidfd patches for v5.1-rc1
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Merge tag 'pidfd-v5.1-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/brauner/linux
Pull pidfd system call from Christian Brauner:
"This introduces the ability to use file descriptors from /proc/<pid>/
as stable handles on struct pid. Even if a pid is recycled the handle
will not change. For a start these fds can be used to send signals to
the processes they refer to.
With the ability to use /proc/<pid> fds as stable handles on struct
pid we can fix a long-standing issue where after a process has exited
its pid can be reused by another process. If a caller sends a signal
to a reused pid it will end up signaling the wrong process.
With this patchset we enable a variety of use cases. One obvious
example is that we can now safely delegate an important part of
process management - sending signals - to processes other than the
parent of a given process by sending file descriptors around via scm
rights and not fearing that the given process will have been recycled
in the meantime. It also allows for easy testing whether a given
process is still alive or not by sending signal 0 to a pidfd which is
quite handy.
There has been some interest in this feature e.g. from systems
management (systemd, glibc) and container managers. I have requested
and gotten comments from glibc to make sure that this syscall is
suitable for their needs as well. In the future I expect it to take on
most other pid-based signal syscalls. But such features are left for
the future once they are needed.
This has been sitting in linux-next for quite a while and has not
caused any issues. It comes with selftests which verify basic
functionality and also test that a recycled pid cannot be signaled via
a pidfd.
Jon has written about a prior version of this patchset. It should
cover the basic functionality since not a lot has changed since then:
https://lwn.net/Articles/773459/
The commit message for the syscall itself is extensively documenting
the syscall, including it's functionality and extensibility"
* tag 'pidfd-v5.1-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/brauner/linux:
selftests: add tests for pidfd_send_signal()
signal: add pidfd_send_signal() syscall
|