kernel/linux.git/fs/jfs, branch v6.12.80

jfs: nlink overflow in jfs_rename

2026-03-04T12:21:10+00:00

[ Upstream commit 9218dc26fd922b09858ecd3666ed57dfd8098da8 ] If nlink is maximal for a directory (-1) and inside that directory you perform a rename for some child directory (not moving from the parent), then the nlink of the first directory is first incremented and later decremented. Normally this is fine, but when nlink = -1 this causes a wrap around to 0, and then drop_nlink issues a warning. After applying the patch syzbot no longer issues any warnings. I also ran some basic fs tests to look for any regressions. Signed-off-by: Jori Koolstra Reported-by: syzbot+9131ddfd7870623b719f@syzkaller.appspotmail.com Closes: https://syzbot.org/bug?extid=9131ddfd7870623b719f Signed-off-by: Dave Kleikamp Signed-off-by: Sasha Levin

jfs: Add missing set_freezable() for freezable kthread

2026-03-04T12:21:10+00:00

[ Upstream commit eb0cfcf265714b419cc3549895a00632e76732ae ] The jfsIOWait() thread calls try_to_freeze() but lacks set_freezable(), causing it to remain non-freezable by default. This prevents proper freezing during system suspend. Add set_freezable() to make the thread freezable as intended. Signed-off-by: Haotian Zhang Signed-off-by: Dave Kleikamp Signed-off-by: Sasha Levin

jfs: fix uninitialized waitqueue in transaction manager

2025-11-13T20:34:27+00:00

[ Upstream commit 300b072df72694ea330c4c673c035253e07827b8 ] The transaction manager initialization in txInit() was not properly initializing TxBlock[0].waitor waitqueue, causing a crash when txEnd(0) is called on read-only filesystems. When a filesystem is mounted read-only, txBegin() returns tid=0 to indicate no transaction. However, txEnd(0) still gets called and tries to access TxBlock[0].waitor via tid_to_tblock(0), but this waitqueue was never initialized because the initialization loop started at index 1 instead of 0. This causes a 'non-static key' lockdep warning and system crash: INFO: trying to register non-static key in txEnd Fix by ensuring all transaction blocks including TxBlock[0] have their waitqueues properly initialized during txInit(). Reported-by: syzbot+c4f3462d8b2ad7977bea@syzkaller.appspotmail.com Signed-off-by: Shaurya Rane Signed-off-by: Dave Kleikamp Signed-off-by: Sasha Levin

jfs: Verify inode mode when loading from disk

2025-11-13T20:34:27+00:00

[ Upstream commit 7a5aa54fba2bd591b22b9b624e6baa9037276986 ] The inode mode loaded from corrupted disk can be invalid. Do like what commit 0a9e74051313 ("isofs: Verify inode mode when loading from disk") does. Reported-by: syzbot Closes: https://syzkaller.appspot.com/bug?extid=895c23f6917da440ed0d Signed-off-by: Tetsuo Handa Signed-off-by: Dave Kleikamp Signed-off-by: Sasha Levin

jfs: upper bound check of tree index in dbAllocAG

2025-08-20T16:30:42+00:00

[ Upstream commit c214006856ff52a8ff17ed8da52d50601d54f9ce ] When computing the tree index in dbAllocAG, we never check if we are out of bounds realative to the size of the stree. This could happen in a scenario where the filesystem metadata are corrupted. Reported-by: syzbot+cffd18309153948f3c3e@syzkaller.appspotmail.com Closes: https://syzkaller.appspot.com/bug?extid=cffd18309153948f3c3e Tested-by: syzbot+cffd18309153948f3c3e@syzkaller.appspotmail.com Signed-off-by: Arnaud Lecomte Signed-off-by: Dave Kleikamp Signed-off-by: Sasha Levin

jfs: Regular file corruption check

2025-08-20T16:30:42+00:00

[ Upstream commit 2d04df8116426b6c7b9f8b9b371250f666a2a2fb ] The reproducer builds a corrupted file on disk with a negative i_size value. Add a check when opening this file to avoid subsequent operation failures. Reported-by: syzbot+630f6d40b3ccabc8e96e@syzkaller.appspotmail.com Closes: https://syzkaller.appspot.com/bug?extid=630f6d40b3ccabc8e96e Tested-by: syzbot+630f6d40b3ccabc8e96e@syzkaller.appspotmail.com Signed-off-by: Edward Adam Davis Signed-off-by: Dave Kleikamp Signed-off-by: Sasha Levin

jfs: truncate good inode pages when hard link is 0

2025-08-20T16:30:42+00:00

[ Upstream commit 2d91b3765cd05016335cd5df5e5c6a29708ec058 ] The fileset value of the inode copy from the disk by the reproducer is AGGR_RESERVED_I. When executing evict, its hard link number is 0, so its inode pages are not truncated. This causes the bugon to be triggered when executing clear_inode() because nrpages is greater than 0. Reported-by: syzbot+6e516bb515d93230bc7b@syzkaller.appspotmail.com Closes: https://syzkaller.appspot.com/bug?extid=6e516bb515d93230bc7b Signed-off-by: Lizhi Xu Signed-off-by: Dave Kleikamp Signed-off-by: Sasha Levin

jfs: fix metapage reference count leak in dbAllocCtl

2025-08-15T10:13:57+00:00

[ Upstream commit 856db37592021e9155384094e331e2d4589f28b1 ] In dbAllocCtl(), read_metapage() increases the reference count of the metapage. However, when dp->tree.budmin < 0, the function returns -EIO without calling release_metapage() to decrease the reference count, leading to a memory leak. Add release_metapage(mp) before the error return to properly manage the metapage reference count and prevent the leak. Fixes: a5f5e4698f8abbb25fe4959814093fb5bfa1aa9d ("jfs: fix shift-out-of-bounds in dbSplit") Signed-off-by: Zheng Yu Signed-off-by: Dave Kleikamp Signed-off-by: Sasha Levin

jfs: reject on-disk inodes of an unsupported type

2025-08-01T08:48:44+00:00

commit 8c3f9a70d2d4dd6c640afe294b05c6a0a45434d9 upstream. Syzbot has reported the following BUG: kernel BUG at fs/inode.c:668! Oops: invalid opcode: 0000 [#1] PREEMPT SMP KASAN PTI CPU: 3 UID: 0 PID: 139 Comm: jfsCommit Not tainted 6.12.0-rc4-syzkaller-00085-g4e46774408d9 #0 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.3-3.fc41 04/01/2014 RIP: 0010:clear_inode+0x168/0x190 Code: 4c 89 f7 e8 ba fe e5 ff e9 61 ff ff ff 44 89 f1 80 e1 07 80 c1 03 38 c1 7c c1 4c 89 f7 e8 90 ff e5 ff eb b7 0b e8 01 5d 7f ff 90 0f 0b e8 f9 5c 7f ff 90 0f 0b e8 f1 5c 7f RSP: 0018:ffffc900027dfae8 EFLAGS: 00010093 RAX: ffffffff82157a87 RBX: 0000000000000001 RCX: ffff888104d4b980 RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000 RBP: ffffc900027dfc90 R08: ffffffff82157977 R09: fffff520004fbf38 R10: dffffc0000000000 R11: fffff520004fbf38 R12: dffffc0000000000 R13: ffff88811315bc00 R14: ffff88811315bda8 R15: ffff88811315bb80 FS: 0000000000000000(0000) GS:ffff888135f00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00005565222e0578 CR3: 0000000026ef0000 CR4: 00000000000006f0 Call Trace: ? __die_body+0x5f/0xb0 ? die+0x9e/0xc0 ? do_trap+0x15a/0x3a0 ? clear_inode+0x168/0x190 ? do_error_trap+0x1dc/0x2c0 ? clear_inode+0x168/0x190 ? __pfx_do_error_trap+0x10/0x10 ? report_bug+0x3cd/0x500 ? handle_invalid_op+0x34/0x40 ? clear_inode+0x168/0x190 ? exc_invalid_op+0x38/0x50 ? asm_exc_invalid_op+0x1a/0x20 ? clear_inode+0x57/0x190 ? clear_inode+0x167/0x190 ? clear_inode+0x168/0x190 ? clear_inode+0x167/0x190 jfs_evict_inode+0xb5/0x440 ? __pfx_jfs_evict_inode+0x10/0x10 evict+0x4ea/0x9b0 ? __pfx_evict+0x10/0x10 ? iput+0x713/0xa50 txUpdateMap+0x931/0xb10 ? __pfx_txUpdateMap+0x10/0x10 jfs_lazycommit+0x49a/0xb80 ? _raw_spin_unlock_irqrestore+0x8f/0x140 ? lockdep_hardirqs_on+0x99/0x150 ? __pfx_jfs_lazycommit+0x10/0x10 ? __pfx_default_wake_function+0x10/0x10 ? __kthread_parkme+0x169/0x1d0 ? __pfx_jfs_lazycommit+0x10/0x10 kthread+0x2f2/0x390 ? __pfx_jfs_lazycommit+0x10/0x10 ? __pfx_kthread+0x10/0x10 ret_from_fork+0x4d/0x80 ? __pfx_kthread+0x10/0x10 ret_from_fork_asm+0x1a/0x30 This happens when 'clear_inode()' makes an attempt to finalize an underlying JFS inode of unknown type. According to JFS layout description from https://jfs.sourceforge.net/project/pub/jfslayout.pdf, inode types from 5 to 15 are reserved for future extensions and should not be encountered on a valid filesystem. So add an extra check for valid inode type in 'copy_from_dinode()'. Reported-by: syzbot+ac2116e48989e84a2893@syzkaller.appspotmail.com Closes: https://syzkaller.appspot.com/bug?extid=ac2116e48989e84a2893 Fixes: 79ac5a46c5c1 ("jfs_lookup(): don't bother with . or ..") Signed-off-by: Dmitry Antipov Signed-off-by: Dave Kleikamp Signed-off-by: Aditya Dutt Signed-off-by: Greg Kroah-Hartman

jfs: validate AG parameters in dbMount() to prevent crashes

2025-07-06T09:01:37+00:00

[ Upstream commit 37bfb464ddca87f203071b5bd562cd91ddc0b40a ] 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: __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: 1da177e4c3f4 ("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 Signed-off-by: Dave Kleikamp Signed-off-by: Sasha Levin