... Log Wrap ... Log Wrap ... Log Wrap ... ================================================================== BUG: KASAN: slab-use-after-free in lmLogSync+0x794/0x7b0 fs/jfs/jfs_logmgr.c:1005 Write of size 4 at addr ffff88802b670a20 by task jfsCommit/110 CPU: 1 UID: 0 PID: 110 Comm: jfsCommit Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x100/0x190 lib/dump_stack.c:120 print_address_description mm/kasan/report.c:378 [inline] print_report+0x156/0x4c9 mm/kasan/report.c:482 kasan_report+0xdf/0x1e0 mm/kasan/report.c:595 lmLogSync+0x794/0x7b0 fs/jfs/jfs_logmgr.c:1005 jfs_syncpt+0x89/0xa0 fs/jfs/jfs_logmgr.c:1041 txEnd+0x318/0x490 fs/jfs/jfs_txnmgr.c:550 txLazyCommit fs/jfs/jfs_txnmgr.c:2685 [inline] jfs_lazycommit+0x748/0xab0 fs/jfs/jfs_txnmgr.c:2734 kthread+0x370/0x450 kernel/kthread.c:467 ret_from_fork+0x754/0xd80 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Allocated by task 6101: kasan_save_stack+0x30/0x50 mm/kasan/common.c:57 kasan_save_track+0x14/0x30 mm/kasan/common.c:78 poison_kmalloc_redzone mm/kasan/common.c:398 [inline] __kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:415 kmalloc_noprof include/linux/slab.h:950 [inline] kzalloc_noprof include/linux/slab.h:1188 [inline] open_inline_log fs/jfs/jfs_logmgr.c:1159 [inline] lmLogOpen+0x571/0x1360 fs/jfs/jfs_logmgr.c:1069 jfs_mount_rw+0x2e0/0x690 fs/jfs/jfs_mount.c:257 jfs_fill_super+0xbc0/0xf50 fs/jfs/super.c:532 get_tree_bdev_flags+0x38c/0x620 fs/super.c:1694 vfs_get_tree+0x92/0x320 fs/super.c:1754 fc_mount fs/namespace.c:1193 [inline] do_new_mount_fc fs/namespace.c:3763 [inline] do_new_mount fs/namespace.c:3839 [inline] path_mount+0x7d0/0x23d0 fs/namespace.c:4159 do_mount fs/namespace.c:4172 [inline] __do_sys_mount fs/namespace.c:4361 [inline] __se_sys_mount fs/namespace.c:4338 [inline] __x64_sys_mount+0x293/0x310 fs/namespace.c:4338 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x106/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f Freed by task 5931: kasan_save_stack+0x30/0x50 mm/kasan/common.c:57 kasan_save_track+0x14/0x30 mm/kasan/common.c:78 kasan_save_free_info+0x3b/0x70 mm/kasan/generic.c:584 poison_slab_object mm/kasan/common.c:253 [inline] __kasan_slab_free+0x5f/0x80 mm/kasan/common.c:285 kasan_slab_free include/linux/kasan.h:235 [inline] slab_free_hook mm/slub.c:2692 [inline] slab_free mm/slub.c:6143 [inline] kfree+0x1f6/0x6b0 mm/slub.c:6461 lmLogClose+0x55f/0x6f0 fs/jfs/jfs_logmgr.c:1460 jfs_umount+0x2f0/0x410 fs/jfs/jfs_umount.c:114 jfs_put_super+0x88/0x1a0 fs/jfs/super.c:194 generic_shutdown_super+0x167/0x360 fs/super.c:646 kill_block_super+0x3b/0xa0 fs/super.c:1725 deactivate_locked_super+0xc1/0x1b0 fs/super.c:476 deactivate_super fs/super.c:509 [inline] deactivate_super+0xe7/0x110 fs/super.c:505 cleanup_mnt+0x21f/0x450 fs/namespace.c:1312 task_work_run+0x150/0x240 kernel/task_work.c:233 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline] __exit_to_user_mode_loop kernel/entry/common.c:67 [inline] exit_to_user_mode_loop+0x100/0x4a0 kernel/entry/common.c:98 __exit_to_user_mode_prepare include/linux/irq-entry-common.h:226 [inline] syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:256 [inline] syscall_exit_to_user_mode include/linux/entry-common.h:325 [inline] do_syscall_64+0x67c/0xf80 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f The buggy address belongs to the object at ffff88802b670800 which belongs to the cache kmalloc-1k of size 1024 The buggy address is located 544 bytes inside of freed 1024-byte region [ffff88802b670800, ffff88802b670c00) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0xffff88802b676800 pfn:0x2b670 head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0 flags: 0xfff00000000240(workingset|head|node=0|zone=1|lastcpupid=0x7ff) page_type: f5(slab) raw: 00fff00000000240 ffff88813fe39dc0 ffffea0001e5e210 ffffea0000dd5610 raw: ffff88802b676800 000000080010000f 00000000f5000000 0000000000000000 head: 00fff00000000240 ffff88813fe39dc0 ffffea0001e5e210 ffffea0000dd5610 head: ffff88802b676800 000000080010000f 00000000f5000000 0000000000000000 head: 00fff00000000003 ffffea0000ad9c01 00000000ffffffff 00000000ffffffff head: ffffffffffffffff 0000000000000000 00000000ffffffff 0000000000000008 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 3, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 5737, tgid 5737 (dhcpcd-run-hook), ts 72398914105, free_ts 72359868782 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x153/0x170 mm/page_alloc.c:1889 prep_new_page mm/page_alloc.c:1897 [inline] get_page_from_freelist+0x111d/0x3140 mm/page_alloc.c:3962 __alloc_frozen_pages_noprof+0x27c/0x2ba0 mm/page_alloc.c:5250 alloc_slab_page mm/slub.c:3269 [inline] allocate_slab mm/slub.c:3458 [inline] new_slab+0xa6/0x6d0 mm/slub.c:3516 refill_objects+0x26b/0x400 mm/slub.c:7153 refill_sheaf mm/slub.c:2818 [inline] alloc_full_sheaf mm/slub.c:2839 [inline] __pcs_replace_empty_main+0x19f/0x600 mm/slub.c:4602 alloc_from_pcs mm/slub.c:4695 [inline] slab_alloc_node mm/slub.c:4829 [inline] __do_kmalloc_node mm/slub.c:5237 [inline] __kmalloc_noprof+0x688/0x850 mm/slub.c:5250 kmalloc_noprof include/linux/slab.h:954 [inline] load_elf_phdrs+0x102/0x210 fs/binfmt_elf.c:541 load_elf_binary+0x29e/0x51b0 fs/binfmt_elf.c:870 search_binary_handler fs/exec.c:1664 [inline] exec_binprm fs/exec.c:1696 [inline] bprm_execve fs/exec.c:1748 [inline] bprm_execve+0x8fb/0x1680 fs/exec.c:1724 do_execveat_common.isra.0+0x4a5/0x580 fs/exec.c:1846 __do_sys_execve fs/exec.c:1930 [inline] __se_sys_execve fs/exec.c:1924 [inline] __x64_sys_execve+0x93/0xd0 fs/exec.c:1924 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x106/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f page last free pid 5736 tgid 5736 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] __free_pages_prepare mm/page_alloc.c:1433 [inline] __free_frozen_pages+0x7e1/0x10d0 mm/page_alloc.c:2978 qlink_free mm/kasan/quarantine.c:163 [inline] qlist_free_all+0x47/0xe0 mm/kasan/quarantine.c:179 kasan_quarantine_reduce+0x1a0/0x1f0 mm/kasan/quarantine.c:286 __kasan_slab_alloc+0x69/0x90 mm/kasan/common.c:350 kasan_slab_alloc include/linux/kasan.h:253 [inline] slab_post_alloc_hook mm/slub.c:4515 [inline] slab_alloc_node mm/slub.c:4844 [inline] __do_kmalloc_node mm/slub.c:5237 [inline] __kmalloc_noprof+0x2b9/0x850 mm/slub.c:5250 kmalloc_noprof include/linux/slab.h:954 [inline] tomoyo_realpath_from_path+0xb6/0x690 security/tomoyo/realpath.c:251 tomoyo_get_realpath security/tomoyo/file.c:151 [inline] tomoyo_path_perm+0x276/0x460 security/tomoyo/file.c:827 security_inode_getattr+0x116/0x280 security/security.c:1869 vfs_getattr fs/stat.c:259 [inline] vfs_fstat+0x4b/0xe0 fs/stat.c:281 __do_sys_newfstat+0x8b/0x110 fs/stat.c:551 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x106/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f Memory state around the buggy address: ffff88802b670900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88802b670980: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff88802b670a00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88802b670a80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88802b670b00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================