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Luís Henriques 50d927880e ocfs2: fix use-after-free when unmounting read-only filesystem
It's trivial to trigger a use-after-free bug in the ocfs2 quotas code using
fstest generic/452.  After a read-only remount, quotas are suspended and
ocfs2_mem_dqinfo is freed through ->ocfs2_local_free_info().  When unmounting
the filesystem, an UAF access to the oinfo will eventually cause a crash.
 
BUG: KASAN: slab-use-after-free in timer_delete+0x54/0xc0
Read of size 8 at addr ffff8880389a8208 by task umount/669
...
Call Trace:
 <TASK>
 ...
 timer_delete+0x54/0xc0
 try_to_grab_pending+0x31/0x230
 __cancel_work_timer+0x6c/0x270
 ocfs2_disable_quotas.isra.0+0x3e/0xf0 [ocfs2]
 ocfs2_dismount_volume+0xdd/0x450 [ocfs2]
 generic_shutdown_super+0xaa/0x280
 kill_block_super+0x46/0x70
 deactivate_locked_super+0x4d/0xb0
 cleanup_mnt+0x135/0x1f0
 ...
 </TASK>

Allocated by task 632:
 kasan_save_stack+0x1c/0x40
 kasan_set_track+0x21/0x30
 __kasan_kmalloc+0x8b/0x90
 ocfs2_local_read_info+0xe3/0x9a0 [ocfs2]
 dquot_load_quota_sb+0x34b/0x680
 dquot_load_quota_inode+0xfe/0x1a0
 ocfs2_enable_quotas+0x190/0x2f0 [ocfs2]
 ocfs2_fill_super+0x14ef/0x2120 [ocfs2]
 mount_bdev+0x1be/0x200
 legacy_get_tree+0x6c/0xb0
 vfs_get_tree+0x3e/0x110
 path_mount+0xa90/0xe10
 __x64_sys_mount+0x16f/0x1a0
 do_syscall_64+0x43/0x90
 entry_SYSCALL_64_after_hwframe+0x72/0xdc

Freed by task 650:
 kasan_save_stack+0x1c/0x40
 kasan_set_track+0x21/0x30
 kasan_save_free_info+0x2a/0x50
 __kasan_slab_free+0xf9/0x150
 __kmem_cache_free+0x89/0x180
 ocfs2_local_free_info+0x2ba/0x3f0 [ocfs2]
 dquot_disable+0x35f/0xa70
 ocfs2_susp_quotas.isra.0+0x159/0x1a0 [ocfs2]
 ocfs2_remount+0x150/0x580 [ocfs2]
 reconfigure_super+0x1a5/0x3a0
 path_mount+0xc8a/0xe10
 __x64_sys_mount+0x16f/0x1a0
 do_syscall_64+0x43/0x90
 entry_SYSCALL_64_after_hwframe+0x72/0xdc

Link: https://lkml.kernel.org/r/20230522102112.9031-1-lhenriques@suse.de
Signed-off-by: Luís Henriques <lhenriques@suse.de>
Reviewed-by: Joseph Qi <joseph.qi@linux.alibaba.com>
Tested-by: Joseph Qi <joseph.qi@linux.alibaba.com>
Cc: Mark Fasheh <mark@fasheh.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Junxiao Bi <junxiao.bi@oracle.com>
Cc: Changwei Ge <gechangwei@live.cn>
Cc: Gang He <ghe@suse.com>
Cc: Jun Piao <piaojun@huawei.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-06-12 11:31:51 -07:00
arch riscv/purgatory: remove PGO flags 2023-06-12 11:31:51 -07:00
block block: make bio_check_eod work for zero sized devices 2023-05-24 08:19:26 -06:00
certs KEYS: Add missing function documentation 2023-04-24 16:15:52 +03:00
crypto This push fixes the following problems: 2023-05-07 10:57:14 -07:00
Documentation Tracing fixes: 2023-05-29 07:20:13 -04:00
drivers phy fixes for 6.4 2023-05-28 20:05:07 -04:00
fs ocfs2: fix use-after-free when unmounting read-only filesystem 2023-06-12 11:31:51 -07:00
include Tracing fixes: 2023-05-29 07:20:13 -04:00
init Objtool changes for v6.4: 2023-04-28 14:02:54 -07:00
io_uring io_uring: unlock sqd->lock before sq thread release CPU 2023-05-25 09:30:13 -06:00
ipc Merge branch 'work.namespace' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2023-02-24 19:20:07 -08:00
kernel kexec: support purgatories with .text.hot sections 2023-06-12 11:31:50 -07:00
lib lib/test_vmalloc.c: avoid garbage in page array 2023-06-12 11:31:51 -07:00
LICENSES LICENSES: Add the copyleft-next-0.3.1 license 2022-11-08 15:44:01 +01:00
mm mm: fix zswap writeback race condition 2023-05-17 15:24:33 -07:00
net Networking fixes for 6.4-rc4, including fixes from bluetooth and bpf 2023-05-25 10:55:26 -07:00
rust Rust changes for v6.4 2023-04-30 11:20:22 -07:00
samples samples/bpf: Drop unnecessary fallthrough 2023-05-16 19:44:05 +02:00
scripts Locking changes in v6.4: 2023-05-05 12:56:55 -07:00
security integrity-v6.4 2023-04-29 10:11:32 -07:00
sound ALSA: hda/realtek: Enable headset onLenovo M70/M90 2023-05-24 14:18:59 +02:00
tools radix-tree: move declarations to header 2023-06-12 11:31:50 -07:00
usr initramfs: Check negative timestamp to prevent broken cpio archive 2023-04-16 17:37:01 +09:00
virt KVM: Fix vcpu_array[0] races 2023-05-19 13:56:26 -04:00
.clang-format cxl for v6.4 2023-04-30 11:51:51 -07:00
.cocciconfig scripts: add Linux .cocciconfig for coccinelle 2016-07-22 12:13:39 +02:00
.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 *.dtso files 2023-02-26 15:28:23 +09:00
.gitignore linux-kselftest-kunit-6.4-rc1 2023-04-24 12:31:32 -07:00
.mailmap mailmap: add entries for Nikolay Aleksandrov 2023-05-17 09:35:05 +01:00
.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: sctp: move Neil to CREDITS 2023-05-12 08:51:32 +01:00
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 ARM: SoC fixes for 6.4 2023-05-26 16:17:56 -07:00
Makefile Linux 6.4-rc4 2023-05-28 07:49:00 -04:00
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.