David Howells a751898a46 fscache: fix OOB Read in __fscache_acquire_volume ... [ Upstream commit 9f0933ac02 ] The type of a->key[0] is char in fscache_volume_same(). If the length of cache volume key is greater than 127, the value of a->key[0] is less than 0. In this case, klen becomes much larger than 255 after type conversion, because the type of klen is size_t. As a result, memcmp() is read out of bounds. This causes a slab-out-of-bounds Read in __fscache_acquire_volume(), as reported by Syzbot. Fix this by changing the type of the stored key to "u8 *" rather than "char *" (it isn't a simple string anyway). Also put in a check that the volume name doesn't exceed NAME_MAX. BUG: KASAN: slab-out-of-bounds in memcmp+0x16f/0x1c0 lib/string.c:757 Read of size 8 at addr ffff888016f3aa90 by task syz-executor344/3613 Call Trace: memcmp+0x16f/0x1c0 lib/string.c:757 memcmp include/linux/fortify-string.h:420 [inline] fscache_volume_same fs/fscache/volume.c:133 [inline] fscache_hash_volume fs/fscache/volume.c:171 [inline] __fscache_acquire_volume+0x76c/0x1080 fs/fscache/volume.c:328 fscache_acquire_volume include/linux/fscache.h:204 [inline] v9fs_cache_session_get_cookie+0x143/0x240 fs/9p/cache.c:34 v9fs_session_init+0x1166/0x1810 fs/9p/v9fs.c:473 v9fs_mount+0xba/0xc90 fs/9p/vfs_super.c:126 legacy_get_tree+0x105/0x220 fs/fs_context.c:610 vfs_get_tree+0x89/0x2f0 fs/super.c:1530 do_new_mount fs/namespace.c:3040 [inline] path_mount+0x1326/0x1e20 fs/namespace.c:3370 do_mount fs/namespace.c:3383 [inline] __do_sys_mount fs/namespace.c:3591 [inline] __se_sys_mount fs/namespace.c:3568 [inline] __x64_sys_mount+0x27f/0x300 fs/namespace.c:3568 Fixes: 62ab633523 ("fscache: Implement volume registration") Reported-by: syzbot+a76f6a6e524cf2080aa3@syzkaller.appspotmail.com Signed-off-by: David Howells <dhowells@redhat.com> Reviewed-by: Zhang Peng <zhangpeng362@huawei.com> Reviewed-by: Jingbo Xu <jefflexu@linux.alibaba.com> cc: Dominique Martinet <asmadeus@codewreck.org> cc: Jeff Layton <jlayton@kernel.org> cc: v9fs-developer@lists.sourceforge.net cc: linux-cachefs@redhat.com Link: https://lore.kernel.org/r/Y3OH+Dmi0QIOK18n@codewreck.org/ # Zhang Peng's v1 fix Link: https://lore.kernel.org/r/20221115140447.2971680-1-zhangpeng362@huawei.com/ # Zhang Peng's v2 fix Link: https://lore.kernel.org/r/166869954095.3793579.8500020902371015443.stgit@warthog.procyon.org.uk/ # v1 Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org>		2022-12-02 17:43:08 +01:00
..
acpi	ACPI: APEI: Fix integer overflow in ghes_estatus_pool_init()	2022-11-10 18:17:24 +01:00
asm-generic	vmlinux.lds.h: Fix placement of '.data..decrypted' section	2022-11-16 10:04:06 +01:00
clocksource	…
crypto	…
drm	drm/edid: Handle EDID 1.4 range descriptor h/vfreq offsets	2022-09-02 16:38:51 +03:00
dt-bindings	dt-bindings: clock: exynosautov9: correct clock numbering of peric0/c1	2022-10-21 12:38:32 +02:00
keys	…
kunit	kunit: fix assert_type for comparison macros	2022-09-01 13:00:32 -06:00
kvm	…
linux	fscache: fix OOB Read in __fscache_acquire_volume	2022-12-02 17:43:08 +01:00
math-emu	…
media	media: v4l: subdev: Fail graciously when getting try data for NULL state	2022-11-10 18:17:24 +01:00
memory	…
misc	…
net	net: neigh: decrement the family specific qlen	2022-12-02 17:43:04 +01:00
pcmcia	…
ras	mm, hwpoison: enable memory error handling on 1GB hugepage	2022-08-08 18:06:44 -07:00
rdma	…
rv	…
scsi	scsi: stex: Properly zero out the passthrough command structure	2022-10-15 08:02:56 +02:00
soc	ARM: at91: pm: avoid soft resetting AC DLL	2022-11-26 09:27:26 +01:00
sound	ASoC: Intel: common: add ACPI matching tables for Raptor Lake	2022-11-04 00:00:28 +09:00
target	…
trace	ARM: SoC fixes for 6.0-rc6	2022-09-22 11:10:11 -07:00
uapi	audit: fix undefined behavior in bit shift for AUDIT_BIT	2022-12-02 17:42:59 +01:00
ufs	scsi: ufs: core: Enable link lost interrupt	2022-08-11 22:04:32 -04:00
vdso	…
video	…
xen	x86/xen: Add support for HVMOP_set_evtchn_upcall_vector	2022-08-12 11:28:21 +02:00