linux/fs/jfs
Vasiliy Kovalev 9242ff6245 jfs: validate AG parameters in dbMount() to prevent crashes
[ Upstream commit 37bfb464dd ]

Validate db_agheight, db_agwidth, and db_agstart in dbMount to catch
corrupted metadata early and avoid undefined behavior in dbAllocAG.
Limits are derived from L2LPERCTL, LPERCTL/MAXAG, and CTLTREESIZE:

- agheight: 0 to L2LPERCTL/2 (0 to 5) ensures shift
  (L2LPERCTL - 2*agheight) >= 0.
- agwidth: 1 to min(LPERCTL/MAXAG, 2^(L2LPERCTL - 2*agheight))
  ensures agperlev >= 1.
  - Ranges: 1-8 (agheight 0-3), 1-4 (agheight 4), 1 (agheight 5).
  - LPERCTL/MAXAG = 1024/128 = 8 limits leaves per AG;
    2^(10 - 2*agheight) prevents division to 0.
- agstart: 0 to CTLTREESIZE-1 - agwidth*(MAXAG-1) keeps ti within
  stree (size 1365).
  - Ranges: 0-1237 (agwidth 1), 0-348 (agwidth 8).

UBSAN: shift-out-of-bounds in fs/jfs/jfs_dmap.c:1400:9
shift exponent -335544310 is negative
CPU: 0 UID: 0 PID: 5822 Comm: syz-executor130 Not tainted 6.14.0-rc5-syzkaller #0
Hardware name: Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:94 [inline]
 dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120
 ubsan_epilogue lib/ubsan.c:231 [inline]
 __ubsan_handle_shift_out_of_bounds+0x3c8/0x420 lib/ubsan.c:468
 dbAllocAG+0x1087/0x10b0 fs/jfs/jfs_dmap.c:1400
 dbDiscardAG+0x352/0xa20 fs/jfs/jfs_dmap.c:1613
 jfs_ioc_trim+0x45a/0x6b0 fs/jfs/jfs_discard.c:105
 jfs_ioctl+0x2cd/0x3e0 fs/jfs/ioctl.c:131
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:906 [inline]
 __se_sys_ioctl+0xf5/0x170 fs/ioctl.c:892
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Found by Linux Verification Center (linuxtesting.org) with Syzkaller.

Cc: stable@vger.kernel.org
Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Reported-by: syzbot+fe8264911355151c487f@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=fe8264911355151c487f
Signed-off-by: Vasiliy Kovalev <kovalev@altlinux.org>
Signed-off-by: Dave Kleikamp <dave.kleikamp@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
History 2025-07-06 10:57:57 +02:00
..
acl.c vfs: add rcu argument to ->get_acl() callback 2021-08-18 22:08:24 +02:00
file.c attr: port attribute changes to new types 2022-06-26 18:18:56 +02:00
inode.c jfs: stop using the nobh helper 2022-08-02 12:34:04 -04:00
ioctl.c block: add a bdev_discard_granularity helper 2022-04-17 19:49:59 -06:00
jfs_acl.h vfs: add rcu argument to ->get_acl() callback 2021-08-18 22:08:24 +02:00
jfs_btree.h treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 156 2019-05-30 11:26:35 -07:00
jfs_debug.c proc: convert everything to "struct proc_ops" 2020-02-04 03:05:26 +00:00
jfs_debug.h treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 156 2019-05-30 11:26:35 -07:00
jfs_dinode.h jfs: define xtree root and page independently 2025-05-02 07:47:08 +02:00
jfs_discard.c jfs: Fix uaf in dbFreeBits 2024-10-17 15:21:44 +02:00
jfs_discard.h treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 156 2019-05-30 11:26:35 -07:00
jfs_dmap.c jfs: validate AG parameters in dbMount() to prevent crashes 2025-07-06 10:57:57 +02:00
jfs_dmap.h jfs: Fix array index bounds check in dbAdjTree 2020-11-13 16:03:07 -06:00
jfs_dtree.c jfs: add index corruption check to DT_GETPAGE() 2025-04-10 14:33:43 +02:00
jfs_dtree.h treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 156 2019-05-30 11:26:35 -07:00
jfs_extent.c jfs: validate max amount of blocks before allocation. 2023-09-13 09:42:49 +02:00
jfs_extent.h jfs: delete duplicated words + other fixes 2020-11-13 13:36:00 -06:00
jfs_filsys.h jfs: jfs_dmap: Validate db_l2nbperpage while mounting 2023-07-23 13:49:34 +02:00
jfs_imap.c jfs: define xtree root and page independently 2025-05-02 07:47:08 +02:00
jfs_imap.h treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 156 2019-05-30 11:26:35 -07:00
jfs_incore.h jfs: define xtree root and page independently 2025-05-02 07:47:08 +02:00
jfs_inode.c inode: make init and permission helpers idmapped mount aware 2021-01-24 14:27:16 +01:00
jfs_inode.h jfs: convert to fileattr 2021-04-12 15:04:29 +02:00
jfs_lock.h treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 156 2019-05-30 11:26:35 -07:00
jfs_logmgr.c fs/jfs: Remove dead code 2022-04-25 14:00:33 -05:00
jfs_logmgr.h jfs: delete duplicated words + other fixes 2020-11-13 13:36:00 -06:00
jfs_metapage.c jfs: Remove check for PageUptodate 2022-06-29 08:51:07 -04:00
jfs_metapage.h treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 156 2019-05-30 11:26:35 -07:00
jfs_mount.c jfs: fix uaf in jfs_evict_inode 2024-02-05 20:12:48 +00:00
jfs_superblock.h treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 156 2019-05-30 11:26:35 -07:00
jfs_txnmgr.c jfs: define xtree root and page independently 2025-05-02 07:47:08 +02:00
jfs_txnmgr.h treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 156 2019-05-30 11:26:35 -07:00
jfs_types.h treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 156 2019-05-30 11:26:35 -07:00
jfs_umount.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 156 2019-05-30 11:26:35 -07:00
jfs_unicode.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 156 2019-05-30 11:26:35 -07:00
jfs_unicode.h treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 156 2019-05-30 11:26:35 -07:00
jfs_uniupr.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 156 2019-05-30 11:26:35 -07:00
jfs_xattr.h jfs: Replace zero-length array with flexible-array member 2020-03-09 15:18:51 -05:00
jfs_xtree.c jfs: define xtree root and page independently 2025-05-02 07:47:08 +02:00
jfs_xtree.h jfs: define xtree root and page independently 2025-05-02 07:47:08 +02:00
Kconfig docs: fix a couple of new broken references 2019-07-31 14:12:26 -06:00
Makefile fs/jfs: Remove dead code 2022-04-25 14:00:33 -05:00
namei.c FS: JFS: Fix null-ptr-deref Read in txBegin 2023-07-27 08:50:33 +02:00
resize.c jfs: use sb_bdev_nr_blocks 2021-10-18 14:43:23 -06:00
super.c block: remove QUEUE_FLAG_DISCARD 2022-04-17 19:49:59 -06:00
symlink.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 156 2019-05-30 11:26:35 -07:00
xattr.c jfs: fix slab-out-of-bounds read in ea_get() 2025-04-10 14:33:43 +02:00