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Gaosheng Cui c7e9624d90 ALSA: mts64: fix possible null-ptr-defer in snd_mts64_interrupt
[ Upstream commit cf2ea3c86ad90d63d1c572b43e1ca9276b0357ad ]

I got a null-ptr-defer error report when I do the following tests
on the qemu platform:

make defconfig and CONFIG_PARPORT=m, CONFIG_PARPORT_PC=m,
CONFIG_SND_MTS64=m

Then making test scripts:
cat>test_mod1.sh<<EOF
modprobe snd-mts64
modprobe snd-mts64
EOF

Executing the script, perhaps several times, we will get a null-ptr-defer
report, as follow:

syzkaller:~# ./test_mod.sh
snd_mts64: probe of snd_mts64.0 failed with error -5
modprobe: ERROR: could not insert 'snd_mts64': No such device
 BUG: kernel NULL pointer dereference, address: 0000000000000000
 #PF: supervisor write access in kernel mode
 #PF: error_code(0x0002) - not-present page
 PGD 0 P4D 0
 Oops: 0002 [#1] PREEMPT SMP PTI
 CPU: 0 PID: 205 Comm: modprobe Not tainted 6.1.0-rc8-00588-g76dcd734eca2 #6
 Call Trace:
  <IRQ>
  snd_mts64_interrupt+0x24/0xa0 [snd_mts64]
  parport_irq_handler+0x37/0x50 [parport]
  __handle_irq_event_percpu+0x39/0x190
  handle_irq_event_percpu+0xa/0x30
  handle_irq_event+0x2f/0x50
  handle_edge_irq+0x99/0x1b0
  __common_interrupt+0x5d/0x100
  common_interrupt+0xa0/0xc0
  </IRQ>
  <TASK>
  asm_common_interrupt+0x22/0x40
 RIP: 0010:_raw_write_unlock_irqrestore+0x11/0x30
  parport_claim+0xbd/0x230 [parport]
  snd_mts64_probe+0x14a/0x465 [snd_mts64]
  platform_probe+0x3f/0xa0
  really_probe+0x129/0x2c0
  __driver_probe_device+0x6d/0xc0
  driver_probe_device+0x1a/0xa0
  __device_attach_driver+0x7a/0xb0
  bus_for_each_drv+0x62/0xb0
  __device_attach+0xe4/0x180
  bus_probe_device+0x82/0xa0
  device_add+0x550/0x920
  platform_device_add+0x106/0x220
  snd_mts64_attach+0x2e/0x80 [snd_mts64]
  port_check+0x14/0x20 [parport]
  bus_for_each_dev+0x6e/0xc0
  __parport_register_driver+0x7c/0xb0 [parport]
  snd_mts64_module_init+0x31/0x1000 [snd_mts64]
  do_one_initcall+0x3c/0x1f0
  do_init_module+0x46/0x1c6
  load_module+0x1d8d/0x1e10
  __do_sys_finit_module+0xa2/0xf0
  do_syscall_64+0x37/0x90
  entry_SYSCALL_64_after_hwframe+0x63/0xcd
  </TASK>
 Kernel panic - not syncing: Fatal exception in interrupt
 Rebooting in 1 seconds..

The mts wa not initialized during interrupt,  we add check for
mts to fix this bug.

Fixes: 68ab801e32 ("[ALSA] Add snd-mts64 driver for ESI Miditerminal 4140")
Signed-off-by: Gaosheng Cui <cuigaosheng1@huawei.com>
Link: https://lore.kernel.org/r/20221206061004.1222966-1-cuigaosheng1@huawei.com
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-01-18 11:41:09 +01:00
arch MIPS: OCTEON: warn only once if deprecated link status is being used 2023-01-18 11:40:58 +01:00
block block: unhash blkdev part inode when the part is deleted 2022-12-19 12:24:16 +01:00
certs certs/blacklist_hashes.c: fix const confusion in certs blacklist 2022-06-22 14:11:22 +02:00
crypto crypto: akcipher - default implementation for setting a private key 2022-10-26 13:22:45 +02:00
Documentation ASoC: dt-bindings: wcd9335: fix reset line polarity in example 2023-01-18 11:41:06 +01:00
drivers media: saa7164: fix missing pci_disable_device() 2023-01-18 11:41:09 +01:00
fs configfs: fix possible memory leak in configfs_create_dir() 2023-01-18 11:41:09 +01:00
include bonding: Rename slave_arr to usable_slaves 2023-01-18 11:41:05 +01:00
init init/Kconfig: fix CC_HAS_ASM_GOTO_TIED_OUTPUT test with dash 2022-12-08 11:22:59 +01:00
ipc ipc/sem: Fix dangling sem_array access in semtimedop race 2022-12-08 11:23:06 +01:00
kernel bpf: propagate precision in ALU/ALU64 operations 2023-01-18 11:41:02 +01:00
lib lib/notifier-error-inject: fix error when writing -errno to debugfs file 2023-01-18 11:40:55 +01:00
LICENSES LICENSES: Rename other to deprecated 2019-05-03 06:34:32 -06:00
mm mm/hugetlb: fix races when looking up a CONT-PTE/PMD size hugetlb page 2022-12-19 12:24:15 +01:00
net bpf, sockmap: fix race in sock_map_free() 2023-01-18 11:41:09 +01:00
samples samples/kretprobes: Fix return value if register_kretprobe() failed 2021-11-17 09:48:39 +01:00
scripts scripts/faddr2line: Fix regression in name resolution on ppc64le 2022-12-08 11:23:02 +01:00
security ima: Fix misuse of dereference of pointer in template_desc_init_fields() 2023-01-18 11:41:03 +01:00
sound ALSA: mts64: fix possible null-ptr-defer in snd_mts64_interrupt 2023-01-18 11:41:09 +01:00
tools netfilter: conntrack: set icmpv6 redirects as RELATED 2023-01-18 11:41:08 +01:00
usr initramfs: restore default compression behavior 2020-04-08 09:08:38 +02:00
virt KVM: arm64: vgic: Fix exit condition in scan_its_table() 2022-10-29 10:20:35 +02:00
.clang-format clang-format: Update with the latest for_each macro list 2019-08-31 10:00:51 +02:00
.cocciconfig
.get_maintainer.ignore Opt out of scripts/get_maintainer.pl 2019-05-16 10:53:40 -07:00
.gitattributes
.gitignore Modules updates for v5.4 2019-09-22 10:34:46 -07:00
.mailmap ARM: SoC fixes 2019-11-10 13:41:59 -08:00
COPYING COPYING: use the new text with points to the license files 2018-03-23 12:41:45 -06:00
CREDITS MAINTAINERS: Remove Simon as Renesas SoC Co-Maintainer 2019-10-10 08:12:51 -07:00
Kbuild kbuild: do not descend to ./Kbuild when cleaning 2019-08-21 21:03:58 +09:00
Kconfig docs: kbuild: convert docs to ReST and rename to *.rst 2019-06-14 14:21:21 -06:00
MAINTAINERS MAINTAINERS: add Chandan as xfs maintainer for 5.4.y 2022-09-28 11:03:58 +02:00
Makefile Linux 5.4.228 2022-12-19 12:24:17 +01:00
README Drop all 00-INDEX files from Documentation/ 2018-09-09 15:08:58 -06:00

Linux kernel
============

There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.

In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``.  The formatted documentation can also be read online at:

    https://www.kernel.org/doc/html/latest/

There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.

Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.