================================================================== BUG: KASAN: slab-use-after-free in jfs_lazycommit+0xa46/0xb30 fs/jfs/jfs_txnmgr.c:2737 Read of size 4 at addr ffff888078b45694 by task jfsCommit/110 CPU: 0 UID: 0 PID: 110 Comm: jfsCommit Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120 print_address_description mm/kasan/report.c:378 [inline] print_report+0xcd/0x630 mm/kasan/report.c:482 kasan_report+0xe0/0x110 mm/kasan/report.c:595 jfs_lazycommit+0xa46/0xb30 fs/jfs/jfs_txnmgr.c:2737 kthread+0x3c5/0x780 kernel/kthread.c:463 ret_from_fork+0x983/0xb10 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246 Allocated by task 15307: kasan_save_stack+0x33/0x60 mm/kasan/common.c:56 kasan_save_track+0x14/0x30 mm/kasan/common.c:77 poison_kmalloc_redzone mm/kasan/common.c:400 [inline] __kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:417 kmalloc_noprof include/linux/slab.h:957 [inline] kzalloc_noprof include/linux/slab.h:1094 [inline] jfs_fill_super+0xca/0x1040 fs/jfs/super.c:452 get_tree_bdev_flags+0x38c/0x620 fs/super.c:1699 vfs_get_tree+0x8e/0x330 fs/super.c:1759 fc_mount fs/namespace.c:1199 [inline] do_new_mount_fc fs/namespace.c:3636 [inline] do_new_mount fs/namespace.c:3712 [inline] path_mount+0x7bf/0x23a0 fs/namespace.c:4022 do_mount fs/namespace.c:4035 [inline] __do_sys_mount fs/namespace.c:4224 [inline] __se_sys_mount fs/namespace.c:4201 [inline] __x64_sys_mount+0x293/0x310 fs/namespace.c:4201 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xcd/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f Freed by task 13016: kasan_save_stack+0x33/0x60 mm/kasan/common.c:56 kasan_save_track+0x14/0x30 mm/kasan/common.c:77 __kasan_save_free_info+0x3b/0x60 mm/kasan/generic.c:587 kasan_save_free_info mm/kasan/kasan.h:406 [inline] poison_slab_object mm/kasan/common.c:252 [inline] __kasan_slab_free+0x5f/0x80 mm/kasan/common.c:284 kasan_slab_free include/linux/kasan.h:234 [inline] slab_free_hook mm/slub.c:2543 [inline] slab_free mm/slub.c:6642 [inline] kfree+0x29e/0x710 mm/slub.c:6849 generic_shutdown_super+0x156/0x390 fs/super.c:643 kill_block_super+0x3b/0x90 fs/super.c:1730 deactivate_locked_super+0xc1/0x1a0 fs/super.c:474 deactivate_super fs/super.c:507 [inline] deactivate_super+0xde/0x100 fs/super.c:503 cleanup_mnt+0x225/0x450 fs/namespace.c:1318 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:44 [inline] exit_to_user_mode_loop+0xfb/0x540 kernel/entry/common.c:75 __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_work include/linux/entry-common.h:159 [inline] syscall_exit_to_user_mode include/linux/entry-common.h:194 [inline] do_syscall_64+0x4ee/0xf80 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f The buggy address belongs to the object at ffff888078b45600 which belongs to the cache kmalloc-256 of size 256 The buggy address is located 148 bytes inside of freed 256-byte region [ffff888078b45600, ffff888078b45700) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x78b44 head: order:1 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0 anon flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff) page_type: f5(slab) raw: 00fff00000000040 ffff88813ff26b40 0000000000000000 dead000000000001 raw: 0000000000000000 0000000000100010 00000000f5000000 0000000000000000 head: 00fff00000000040 ffff88813ff26b40 0000000000000000 dead000000000001 head: 0000000000000000 0000000000100010 00000000f5000000 0000000000000000 head: 00fff00000000001 ffffea0001e2d101 00000000ffffffff 00000000ffffffff head: ffffffffffffffff 0000000000000000 00000000ffffffff 0000000000000002 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 1, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 5849, tgid 5849 (syz-executor), ts 112325728669, free_ts 112324844149 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x1af/0x220 mm/page_alloc.c:1845 prep_new_page mm/page_alloc.c:1853 [inline] get_page_from_freelist+0xd0b/0x31a0 mm/page_alloc.c:3879 __alloc_frozen_pages_noprof+0x25f/0x2440 mm/page_alloc.c:5178 alloc_pages_mpol+0x1fb/0x550 mm/mempolicy.c:2416 alloc_slab_page mm/slub.c:3059 [inline] allocate_slab mm/slub.c:3232 [inline] new_slab+0x24a/0x360 mm/slub.c:3286 ___slab_alloc+0xee7/0x1cd0 mm/slub.c:4655 __slab_alloc.constprop.0+0x63/0x110 mm/slub.c:4778 __slab_alloc_node mm/slub.c:4854 [inline] slab_alloc_node mm/slub.c:5276 [inline] __do_kmalloc_node mm/slub.c:5649 [inline] __kmalloc_noprof+0x501/0x870 mm/slub.c:5662 kmalloc_noprof include/linux/slab.h:961 [inline] kzalloc_noprof include/linux/slab.h:1094 [inline] fib_create_info+0x53f/0x4680 net/ipv4/fib_semantics.c:1402 fib_table_insert+0x177/0x1c40 net/ipv4/fib_trie.c:1212 fib_magic+0x4d4/0x5c0 net/ipv4/fib_frontend.c:1134 fib_add_ifaddr+0x16d/0x580 net/ipv4/fib_frontend.c:1156 fib_netdev_event+0x38a/0x710 net/ipv4/fib_frontend.c:1516 notifier_call_chain+0xbc/0x3e0 kernel/notifier.c:85 call_netdevice_notifiers_info+0xbe/0x110 net/core/dev.c:2229 call_netdevice_notifiers_extack net/core/dev.c:2267 [inline] call_netdevice_notifiers net/core/dev.c:2281 [inline] __dev_notify_flags+0x12c/0x2e0 net/core/dev.c:9676 page last free pid 5849 tgid 5849 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1394 [inline] __free_frozen_pages+0x7df/0x1160 mm/page_alloc.c:2901 discard_slab mm/slub.c:3330 [inline] __put_partials+0x130/0x170 mm/slub.c:3876 qlink_free mm/kasan/quarantine.c:163 [inline] qlist_free_all+0x4d/0x120 mm/kasan/quarantine.c:179 kasan_quarantine_reduce+0x195/0x1e0 mm/kasan/quarantine.c:286 __kasan_slab_alloc+0x69/0x90 mm/kasan/common.c:352 kasan_slab_alloc include/linux/kasan.h:252 [inline] slab_post_alloc_hook mm/slub.c:4978 [inline] slab_alloc_node mm/slub.c:5288 [inline] __do_kmalloc_node mm/slub.c:5649 [inline] __kmalloc_noprof+0x2e8/0x870 mm/slub.c:5662 kmalloc_noprof include/linux/slab.h:961 [inline] kzalloc_noprof include/linux/slab.h:1094 [inline] fib_create_info+0x53f/0x4680 net/ipv4/fib_semantics.c:1402 fib_table_insert+0x177/0x1c40 net/ipv4/fib_trie.c:1212 fib_magic+0x4d4/0x5c0 net/ipv4/fib_frontend.c:1134 fib_add_ifaddr+0x4d2/0x580 net/ipv4/fib_frontend.c:1178 fib_inetaddr_event+0x147/0x270 net/ipv4/fib_frontend.c:1470 notifier_call_chain+0xbc/0x3e0 kernel/notifier.c:85 blocking_notifier_call_chain kernel/notifier.c:380 [inline] blocking_notifier_call_chain+0x69/0xa0 kernel/notifier.c:368 __inet_insert_ifa+0x925/0xc80 net/ipv4/devinet.c:566 inet_insert_ifa net/ipv4/devinet.c:578 [inline] inet_insert_ifa net/ipv4/devinet.c:571 [inline] inetdev_event+0xaee/0x1840 net/ipv4/devinet.c:1627 notifier_call_chain+0xbc/0x3e0 kernel/notifier.c:85 Memory state around the buggy address: ffff888078b45580: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff888078b45600: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff888078b45680: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff888078b45700: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff888078b45780: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ==================================================================