kernel/linux
0
Fork 0
mirror of https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ synced 2026-10-26 19:14:18 +00:00
Code Issues Releases Packages Activity
No description
1,227,524 commits 117 branches 5,805 tags 5.9 GiB
  • C 96.8%
  • Assembly 0.9%
  • Rust 0.7%
  • Shell 0.6%
  • Python 0.5%
  • Other 0.3%
Find a file
Baokun Li e0d724932a fscache: delete fscache_cookie_lru_timer when fscache exits to avoid UAF 
commit 72a6e22c60 upstream.

The fscache_cookie_lru_timer is initialized when the fscache module
is inserted, but is not deleted when the fscache module is removed.
If timer_reduce() is called before removing the fscache module,
the fscache_cookie_lru_timer will be added to the timer list of
the current cpu. Afterwards, a use-after-free will be triggered
in the softIRQ after removing the fscache module, as follows:

==================================================================
BUG: unable to handle page fault for address: fffffbfff803c9e9
 PF: supervisor read access in kernel mode
 PF: error_code(0x0000) - not-present page
PGD 21ffea067 P4D 21ffea067 PUD 21ffe6067 PMD 110a7c067 PTE 0
Oops: Oops: 0000 [#1] PREEMPT SMP KASAN PTI
CPU: 1 UID: 0 PID: 0 Comm: swapper/1 Tainted: G W 6.11.0-rc3 #855
Tainted: [W]=WARN
RIP: 0010:__run_timer_base.part.0+0x254/0x8a0
Call Trace:
 <IRQ>
 tmigr_handle_remote_up+0x627/0x810
 __walk_groups.isra.0+0x47/0x140
 tmigr_handle_remote+0x1fa/0x2f0
 handle_softirqs+0x180/0x590
 irq_exit_rcu+0x84/0xb0
 sysvec_apic_timer_interrupt+0x6e/0x90
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20
RIP: 0010:default_idle+0xf/0x20
 default_idle_call+0x38/0x60
 do_idle+0x2b5/0x300
 cpu_startup_entry+0x54/0x60
 start_secondary+0x20d/0x280
 common_startup_64+0x13e/0x148
 </TASK>
Modules linked in: [last unloaded: netfs]
==================================================================

Therefore delete fscache_cookie_lru_timer when removing the fscahe module.

Fixes: 12bb21a29c ("fscache: Implement cookie user counting and resource pinning")
Cc: stable@kernel.org
Signed-off-by: Baokun Li <libaokun1@huawei.com>
Link: https://lore.kernel.org/r/20240826112056.2458299-1-libaokun@huaweicloud.com
Acked-by: David Howells <dhowells@redhat.com>
Signed-off-by: Christian Brauner <brauner@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
History 2024-09-12 11:11:27 +02:00
arch
block
certs
crypto
Documentation
drivers
fs
include
init
io_uring
ipc
kernel
lib
LICENSES
mm
net
rust
samples
scripts
security
sound
tools
usr
virt
.clang-format
.cocciconfig
.get_maintainer.ignore
.gitattributes
.gitignore
.mailmap
.rustfmt.toml
COPYING
CREDITS
Kbuild
Kconfig
MAINTAINERS
Makefile
README

README 

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.