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ChenXiaoSong 1228934cf2 ntfs: fix use-after-free in ntfs_ucsncmp()
commit 38c9c22a85aeed28d0831f230136e9cf6fa2ed44 upstream.

Syzkaller reported use-after-free bug as follows:

==================================================================
BUG: KASAN: use-after-free in ntfs_ucsncmp+0x123/0x130
Read of size 2 at addr ffff8880751acee8 by task a.out/879

CPU: 7 PID: 879 Comm: a.out Not tainted 5.19.0-rc4-next-20220630-00001-gcc5218c8bd2c-dirty #7
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.0-0-gd239552ce722-prebuilt.qemu.org 04/01/2014
Call Trace:
 <TASK>
 dump_stack_lvl+0x1c0/0x2b0
 print_address_description.constprop.0.cold+0xd4/0x484
 print_report.cold+0x55/0x232
 kasan_report+0xbf/0xf0
 ntfs_ucsncmp+0x123/0x130
 ntfs_are_names_equal.cold+0x2b/0x41
 ntfs_attr_find+0x43b/0xb90
 ntfs_attr_lookup+0x16d/0x1e0
 ntfs_read_locked_attr_inode+0x4aa/0x2360
 ntfs_attr_iget+0x1af/0x220
 ntfs_read_locked_inode+0x246c/0x5120
 ntfs_iget+0x132/0x180
 load_system_files+0x1cc6/0x3480
 ntfs_fill_super+0xa66/0x1cf0
 mount_bdev+0x38d/0x460
 legacy_get_tree+0x10d/0x220
 vfs_get_tree+0x93/0x300
 do_new_mount+0x2da/0x6d0
 path_mount+0x496/0x19d0
 __x64_sys_mount+0x284/0x300
 do_syscall_64+0x3b/0xc0
 entry_SYSCALL_64_after_hwframe+0x46/0xb0
RIP: 0033:0x7f3f2118d9ea
Code: 48 8b 0d a9 f4 0b 00 f7 d8 64 89 01 48 83 c8 ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 49 89 ca b8 a5 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d 76 f4 0b 00 f7 d8 64 89 01 48
RSP: 002b:00007ffc269deac8 EFLAGS: 00000202 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f3f2118d9ea
RDX: 0000000020000000 RSI: 0000000020000100 RDI: 00007ffc269dec00
RBP: 00007ffc269dec80 R08: 00007ffc269deb00 R09: 00007ffc269dec44
R10: 0000000000000000 R11: 0000000000000202 R12: 000055f81ab1d220
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
 </TASK>

The buggy address belongs to the physical page:
page:0000000085430378 refcount:1 mapcount:1 mapping:0000000000000000 index:0x555c6a81d pfn:0x751ac
memcg:ffff888101f7e180
anon flags: 0xfffffc00a0014(uptodate|lru|mappedtodisk|swapbacked|node=0|zone=1|lastcpupid=0x1fffff)
raw: 000fffffc00a0014 ffffea0001bf2988 ffffea0001de2448 ffff88801712e201
raw: 0000000555c6a81d 0000000000000000 0000000100000000 ffff888101f7e180
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff8880751acd80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff8880751ace00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>ffff8880751ace80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
                                                          ^
 ffff8880751acf00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff8880751acf80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
==================================================================

The reason is that struct ATTR_RECORD->name_offset is 6485, end address of
name string is out of bounds.

Fix this by adding sanity check on end address of attribute name string.

[akpm@linux-foundation.org: coding-style cleanups]
[chenxiaosong2@huawei.com: cleanup suggested by Hawkins Jiawei]
  Link: https://lkml.kernel.org/r/20220709064511.3304299-1-chenxiaosong2@huawei.com
Link: https://lkml.kernel.org/r/20220707105329.4020708-1-chenxiaosong2@huawei.com
Signed-off-by: ChenXiaoSong <chenxiaosong2@huawei.com>
Signed-off-by: Hawkins Jiawei <yin31149@gmail.com>
Cc: Anton Altaparmakov <anton@tuxera.com>
Cc: ChenXiaoSong <chenxiaosong2@huawei.com>
Cc: Yongqiang Liu <liuyongqiang13@huawei.com>
Cc: Zhang Yi <yi.zhang@huawei.com>
Cc: Zhang Xiaoxu <zhangxiaoxu5@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-08-03 12:00:43 +02:00
arch tty: the rest, stop using tty_schedule_flip() 2022-07-29 17:19:28 +02:00
block block: Fix handling of offline queues in blk_mq_alloc_request_hctx() 2022-06-22 14:13:17 +02:00
certs certs/blacklist_hashes.c: fix const confusion in certs blacklist 2022-06-22 14:13:17 +02:00
crypto crypto: memneq - move into lib/ 2022-06-22 14:13:18 +02:00
Documentation docs: net: explain struct net_device lifetime 2022-07-29 17:19:07 +02:00
drivers net: usb: ax88179_178a needs FLAG_SEND_ZLP 2022-07-29 17:19:29 +02:00
fs ntfs: fix use-after-free in ntfs_ucsncmp() 2022-08-03 12:00:43 +02:00
include Bluetooth: L2CAP: Fix use-after-free caused by l2cap_chan_put 2022-08-03 12:00:43 +02:00
init Kconfig: Add option for asm goto w/ tied outputs to workaround clang-13 bug 2022-06-09 10:21:25 +02:00
ipc ipc/mqueue: use get_tree_nodev() in mqueue_get_tree() 2022-06-09 10:21:17 +02:00
kernel watch-queue: remove spurious double semicolon 2022-07-29 17:19:29 +02:00
lib ida: don't use BUG_ON() for debugging 2022-07-12 16:32:23 +02:00
LICENSES LICENSES/deprecated: add Zlib license text 2020-09-16 14:33:49 +02:00
mm mm/mempolicy: fix uninit-value in mpol_rebind_policy() 2022-07-29 17:19:23 +02:00
net Bluetooth: L2CAP: Fix use-after-free caused by l2cap_chan_put 2022-08-03 12:00:43 +02:00
samples x86: Prepare inline-asm for straight-line-speculation 2022-07-25 11:26:29 +02:00
scripts x86/retbleed: Add fine grained Kconfig knobs 2022-07-25 11:26:50 +02:00
security lockdown: Fix kexec lockdown bypass with ima policy 2022-07-29 17:19:06 +02:00
sound ALSA: memalloc: Align buffer allocations in page size 2022-07-29 17:19:25 +02:00
tools tools headers: Remove broken definition of __LITTLE_ENDIAN 2022-07-25 11:26:56 +02:00
usr usr/include/Makefile: add linux/nfc.h to the compile-test coverage 2022-02-01 17:25:48 +01:00
virt KVM: Don't null dereference ops->destroy 2022-07-29 17:19:23 +02:00
.clang-format RDMA 5.10 pull request 2020-10-17 11:18:18 -07:00
.cocciconfig
.get_maintainer.ignore Opt out of scripts/get_maintainer.pl 2019-05-16 10:53:40 -07:00
.gitattributes .gitattributes: use 'dts' diff driver for dts files 2019-12-04 19:44:11 -08:00
.gitignore kbuild: generate Module.symvers only when vmlinux exists 2021-05-19 10:12:59 +02:00
.mailmap mailmap: add two more addresses of Uwe Kleine-König 2020-12-06 10:19:07 -08:00
COPYING COPYING: state that all contributions really are covered by this file 2020-02-10 13:32:20 -08:00
CREDITS MAINTAINERS: Move Jason Cooper to CREDITS 2020-11-30 10:20:34 +01:00
Kbuild kbuild: rename hostprogs-y/always to hostprogs/always-y 2020-02-04 01:53:07 +09:00
Kconfig kbuild: ensure full rebuild when the compiler is updated 2020-05-12 13:28:33 +09:00
MAINTAINERS MAINTAINERS: add Amir as xfs maintainer for 5.10.y 2022-07-02 16:39:22 +02:00
Makefile Linux 5.10.134 2022-07-29 17:19:29 +02:00
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
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Documentation/admin-guide/README.rst first.

In order to build the documentation, use ``make htmldocs`` or
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    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.