Kernel for Galaxy S24, rebased on CLO sources (WIP)
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Dave Wysochanski b5b52de321 fscache: Fix oops due to race with cookie_lru and use_cookie
If a cookie expires from the LRU and the LRU_DISCARD flag is set, but
the state machine has not run yet, it's possible another thread can call
fscache_use_cookie and begin to use it.

When the cookie_worker finally runs, it will see the LRU_DISCARD flag
set, transition the cookie->state to LRU_DISCARDING, which will then
withdraw the cookie.  Once the cookie is withdrawn the object is removed
the below oops will occur because the object associated with the cookie
is now NULL.

Fix the oops by clearing the LRU_DISCARD bit if another thread uses the
cookie before the cookie_worker runs.

  BUG: kernel NULL pointer dereference, address: 0000000000000008
  ...
  CPU: 31 PID: 44773 Comm: kworker/u130:1 Tainted: G     E    6.0.0-5.dneg.x86_64 #1
  Hardware name: Google Compute Engine/Google Compute Engine, BIOS Google 08/26/2022
  Workqueue: events_unbound netfs_rreq_write_to_cache_work [netfs]
  RIP: 0010:cachefiles_prepare_write+0x28/0x90 [cachefiles]
  ...
  Call Trace:
    netfs_rreq_write_to_cache_work+0x11c/0x320 [netfs]
    process_one_work+0x217/0x3e0
    worker_thread+0x4a/0x3b0
    kthread+0xd6/0x100

Fixes: 12bb21a29c ("fscache: Implement cookie user counting and resource pinning")
Reported-by: Daire Byrne <daire.byrne@gmail.com>
Signed-off-by: Dave Wysochanski <dwysocha@redhat.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Tested-by: Daire Byrne <daire@dneg.com>
Link: https://lore.kernel.org/r/20221117115023.1350181-1-dwysocha@redhat.com/ # v1
Link: https://lore.kernel.org/r/20221117142915.1366990-1-dwysocha@redhat.com/ # v2
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2022-12-07 11:49:18 -08:00
arch Revert the dropping of the cache invalidation from the arm64 2022-12-06 11:03:03 -08:00
block block-6.1-2022-11-25 2022-11-25 17:50:57 -08:00
certs certs: make system keyring depend on built-in x509 parser 2022-09-24 04:31:18 +09:00
crypto treewide: use get_random_bytes() when possible 2022-10-11 17:42:58 -06:00
Documentation * Document the interaction between KVM_CAP_HALT_POLL and halt_poll_ns 2022-12-06 10:49:19 -08:00
drivers media: videobuf2-core: take mmap_lock in vb2_get_unmapped_area() 2022-12-07 11:25:40 -08:00
fs fscache: Fix oops due to race with cookie_lru and use_cookie 2022-12-07 11:49:18 -08:00
include fscache: Fix oops due to race with cookie_lru and use_cookie 2022-12-07 11:49:18 -08:00
init init/Kconfig: fix CC_HAS_ASM_GOTO_TIED_OUTPUT test with dash 2022-11-22 22:42:38 +09:00
io_uring io_uring: clear TIF_NOTIFY_SIGNAL if set and task_work not available 2022-11-25 10:55:08 -07:00
ipc ipc/sem: Fix dangling sem_array access in semtimedop race 2022-12-05 10:54:44 -08:00
kernel proc: proc_skip_spaces() shouldn't think it is working on C strings 2022-12-05 12:09:06 -08:00
lib 15 hotfixes. 11 marked cc:stable. Only three or four of the latter 2022-12-02 13:39:38 -08:00
LICENSES LICENSES/LGPL-2.1: Add LGPL-2.1-or-later as valid identifiers 2021-12-16 14:33:10 +01:00
mm Revert "mm: align larger anonymous mappings on THP boundaries" 2022-12-04 12:51:59 -08:00
net Including fixes from bpf, can and wifi. 2022-11-29 09:52:10 -08:00
rust Kbuild: add Rust support 2022-09-28 09:02:20 +02:00
samples VFIO updates for v6.1-rc1 2022-10-12 14:46:48 -07:00
scripts - Handle different output of readelf on different distros running 2022-11-27 12:08:17 -08:00
security lsm/stable-6.1 PR 20221031 2022-10-31 12:09:42 -07:00
sound ASoC: Fixes for v6.1 2022-11-30 17:26:55 +01:00
tools 15 hotfixes. 11 marked cc:stable. Only three or four of the latter 2022-12-02 13:39:38 -08:00
usr usr/gen_init_cpio.c: remove unnecessary -1 values from int file 2022-10-03 14:21:44 -07:00
virt Merge branch 'kvm-dwmw2-fixes' into HEAD 2022-11-23 18:59:45 -05:00
.clang-format PCI/DOE: Add DOE mailbox support functions 2022-07-19 15:38:04 -07:00
.cocciconfig
.get_maintainer.ignore get_maintainer: add Alan to .get_maintainer.ignore 2022-08-20 15:17:44 -07:00
.gitattributes .gitattributes: use 'dts' diff driver for dts files 2019-12-04 19:44:11 -08:00
.gitignore Kbuild: add Rust support 2022-09-28 09:02:20 +02:00
.mailmap Including fixes from bpf, can and wifi. 2022-11-29 09:52:10 -08:00
.rustfmt.toml rust: add .rustfmt.toml 2022-09-28 09:02:20 +02:00
COPYING COPYING: state that all contributions really are covered by this file 2020-02-10 13:32:20 -08:00
CREDITS MAINTAINERS: Remove Michal Marek from Kbuild maintainers 2022-11-16 14:53:00 +09:00
Kbuild Kbuild updates for v6.1 2022-10-10 12:00:45 -07:00
Kconfig kbuild: ensure full rebuild when the compiler is updated 2020-05-12 13:28:33 +09:00
MAINTAINERS Including fixes from bpf, can and wifi. 2022-11-29 09:52:10 -08:00
Makefile Linux 6.1-rc8 2022-12-04 14:48:12 -08:00
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.