syzbot


KASAN: use-after-free Read in xfs_inode_item_push (3)

Status: upstream: reported on 2026/01/22 12:51
Reported-by: syzbot+2e2883b75fabb8171bd8@syzkaller.appspotmail.com
First crash: 6d21h, last: 6d21h
Similar bugs (8)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-6.1 KASAN: use-after-free Read in xfs_inode_item_push (2) 19 1 510d 510d 0/3 auto-obsoleted due to no activity on 2024/12/14 11:37
upstream KASAN: use-after-free Read in xfs_inode_item_push xfs 19 16 858d 1084d 0/29 auto-obsoleted due to no activity on 2024/01/02 00:00
linux-6.1 KASAN: use-after-free Read in xfs_inode_item_push 19 1 1005d 1005d 0/3 auto-obsoleted due to no activity on 2023/08/23 09:03
linux-5.15 KASAN: use-after-free Read in xfs_inode_item_push (2) origin:lts-only 19 C inconclusive 2 235d 363d 0/3 upstream: reported C repro on 2025/01/31 01:44
linux-5.15 KASAN: use-after-free Read in xfs_inode_item_push 19 2 985d 987d 0/3 auto-obsoleted due to no activity on 2023/08/28 08:02
upstream KASAN: slab-use-after-free Read in xfs_inode_item_push xfs 19 C error 318 1d11h 658d 0/29 upstream: reported C repro on 2024/04/10 12:45
linux-6.6 KFENCE: use-after-free read in xfs_inode_item_push 19 2 108d 115d 0/2 auto-obsoleted due to no activity on 2026/01/20 14:10
linux-6.6 KASAN: slab-use-after-free Read in xfs_inode_item_push 19 1 1d20h 1d20h 0/2 upstream: reported on 2026/01/27 13:32

Sample crash report:
==================================================================
BUG: KASAN: use-after-free in xfs_inode_item_push+0x240/0x28c fs/xfs/xfs_inode_item.c:776
Read of size 8 at addr ffff0000e0640d00 by task xfsaild/loop5/8963

CPU: 0 PID: 8963 Comm: xfsaild/loop5 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/03/2025
Call trace:
 dump_backtrace+0x1c0/0x1ec arch/arm64/kernel/stacktrace.c:158
 show_stack+0x2c/0x3c arch/arm64/kernel/stacktrace.c:165
 __dump_stack+0x30/0x40 lib/dump_stack.c:88
 dump_stack_lvl+0xf4/0x15c lib/dump_stack.c:106
 print_address_description+0x88/0x218 mm/kasan/report.c:316
 print_report+0x50/0x68 mm/kasan/report.c:420
 kasan_report+0xa8/0xfc mm/kasan/report.c:524
 __asan_report_load8_noabort+0x2c/0x38 mm/kasan/report_generic.c:351
 xfs_inode_item_push+0x240/0x28c fs/xfs/xfs_inode_item.c:776
 xfsaild_push_item fs/xfs/xfs_trans_ail.c:414 [inline]
 xfsaild_push fs/xfs/xfs_trans_ail.c:484 [inline]
 xfsaild+0xaa4/0x2848 fs/xfs/xfs_trans_ail.c:669
 kthread+0x250/0x2d8 kernel/kthread.c:376
 ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:850

Allocated by task 8973:
 kasan_save_stack mm/kasan/common.c:46 [inline]
 kasan_set_track+0x4c/0x80 mm/kasan/common.c:53
 kasan_save_alloc_info+0x24/0x30 mm/kasan/generic.c:505
 __kasan_slab_alloc+0x70/0x88 mm/kasan/common.c:329
 kasan_slab_alloc include/linux/kasan.h:201 [inline]
 slab_post_alloc_hook+0x74/0x430 mm/slab.h:737
 slab_alloc_node mm/slub.c:3359 [inline]
 slab_alloc mm/slub.c:3367 [inline]
 __kmem_cache_alloc_lru mm/slub.c:3374 [inline]
 kmem_cache_alloc+0x22c/0x308 mm/slub.c:3383
 kmem_cache_zalloc include/linux/slab.h:689 [inline]
 xfs_inode_item_init+0x3c/0xc0 fs/xfs/xfs_inode_item.c:871
 xfs_trans_ijoin+0xd4/0x120 fs/xfs/libxfs/xfs_trans_inode.c:36
 xfs_setattr_size+0x464/0xb1c fs/xfs/xfs_iops.c:905
 xfs_vn_setattr_size fs/xfs/xfs_iops.c:991 [inline]
 xfs_vn_setattr+0x2f8/0x37c fs/xfs/xfs_iops.c:1016
 notify_change+0xb0c/0xdcc fs/attr.c:499
 do_truncate+0x188/0x20c fs/open.c:65
 handle_truncate fs/namei.c:3293 [inline]
 do_open fs/namei.c:3638 [inline]
 path_openat+0x2110/0x26bc fs/namei.c:3791
 do_filp_open+0x194/0x384 fs/namei.c:3818
 do_sys_openat2+0x134/0x3f4 fs/open.c:1320
 do_sys_open fs/open.c:1336 [inline]
 __do_sys_openat fs/open.c:1352 [inline]
 __se_sys_openat fs/open.c:1347 [inline]
 __arm64_sys_openat+0x118/0x14c fs/open.c:1347
 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
 invoke_syscall+0x98/0x2b4 arch/arm64/kernel/syscall.c:52
 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:140
 do_el0_svc+0x58/0x130 arch/arm64/kernel/syscall.c:204
 el0_svc+0x58/0x128 arch/arm64/kernel/entry-common.c:637
 el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:655
 el0t_64_sync+0x18c/0x190 arch/arm64/kernel/entry.S:585

Freed by task 21:
 kasan_save_stack mm/kasan/common.c:46 [inline]
 kasan_set_track+0x4c/0x80 mm/kasan/common.c:53
 kasan_save_free_info+0x38/0x5c mm/kasan/generic.c:516
 ____kasan_slab_free+0x148/0x1b0 mm/kasan/common.c:237
 __kasan_slab_free+0x18/0x28 mm/kasan/common.c:245
 kasan_slab_free include/linux/kasan.h:177 [inline]
 slab_free_hook mm/slub.c:1729 [inline]
 slab_free_freelist_hook+0x16c/0x1e8 mm/slub.c:1755
 slab_free mm/slub.c:3687 [inline]
 kmem_cache_free+0x118/0x314 mm/slub.c:3709
 xfs_inode_item_destroy+0x70/0x84 fs/xfs/xfs_inode_item.c:893
 xfs_inode_free_callback+0x14c/0x1bc fs/xfs/xfs_icache.c:145
 rcu_do_batch kernel/rcu/tree.c:2297 [inline]
 rcu_core+0x828/0x18b0 kernel/rcu/tree.c:2557
 rcu_core_si+0x10/0x1c kernel/rcu/tree.c:2574
 handle_softirqs+0x318/0xc60 kernel/softirq.c:596
 run_ksoftirqd+0x7c/0x2ac kernel/softirq.c:968
 smpboot_thread_fn+0x4b0/0x964 kernel/smpboot.c:164
 kthread+0x250/0x2d8 kernel/kthread.c:376
 ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:850

The buggy address belongs to the object at ffff0000e0640cd0
 which belongs to the cache xfs_ili of size 264
The buggy address is located 48 bytes inside of
 264-byte region [ffff0000e0640cd0, ffff0000e0640dd8)

The buggy address belongs to the physical page:
page:0000000072eab60e refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff0000e0640b88 pfn:0x120640
flags: 0x5ffc00000000200(slab|node=0|zone=2|lastcpupid=0x7ff)
raw: 05ffc00000000200 fffffc0003880580 dead000000000003 ffff0000c4c18d80
raw: ffff0000e0640b88 00000000800c000a 00000001ffffffff 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff0000e0640c00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff0000e0640c80: fb fb fc fc fc fc fc fc fc fc fa fb fb fb fb fb
>ffff0000e0640d00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                   ^
 ffff0000e0640d80: fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc fc
 ffff0000e0640e00: fc fc fc fa fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/01/22 12:50 linux-6.1.y cd9b81672742 a16aed1d .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 KASAN: use-after-free Read in xfs_inode_item_push
* Struck through repros no longer work on HEAD.