================================================================== BUG: KASAN: slab-use-after-free in jfs_lazycommit+0x7e0/0xb80 fs/jfs/jfs_txnmgr.c:2736 Read of size 4 at addr ffff88804afbd294 by task jfsCommit/110 CPU: 1 UID: 0 PID: 110 Comm: jfsCommit Not tainted 6.12.0-rc1-syzkaller-00165-g360c1f1f24c6 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120 print_address_description mm/kasan/report.c:377 [inline] print_report+0x169/0x550 mm/kasan/report.c:488 kasan_report+0x143/0x180 mm/kasan/report.c:601 jfs_lazycommit+0x7e0/0xb80 fs/jfs/jfs_txnmgr.c:2736 kthread+0x2f2/0x390 kernel/kthread.c:389 ret_from_fork+0x4d/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 Allocated by task 21605: kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3f/0x80 mm/kasan/common.c:68 poison_kmalloc_redzone mm/kasan/common.c:377 [inline] __kasan_kmalloc+0x98/0xb0 mm/kasan/common.c:394 kasan_kmalloc include/linux/kasan.h:257 [inline] __kmalloc_cache_noprof+0x19c/0x2c0 mm/slub.c:4296 kmalloc_noprof include/linux/slab.h:878 [inline] kzalloc_noprof include/linux/slab.h:1014 [inline] jfs_fill_super+0xff/0xc50 fs/jfs/super.c:495 mount_bdev+0x20c/0x2d0 fs/super.c:1679 legacy_get_tree+0xf0/0x190 fs/fs_context.c:662 vfs_get_tree+0x92/0x2b0 fs/super.c:1800 do_new_mount+0x2be/0xb40 fs/namespace.c:3507 do_mount fs/namespace.c:3847 [inline] __do_sys_mount fs/namespace.c:4055 [inline] __se_sys_mount+0x2d6/0x3c0 fs/namespace.c:4032 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 Freed by task 10824: kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3f/0x80 mm/kasan/common.c:68 kasan_save_free_info+0x40/0x50 mm/kasan/generic.c:579 poison_slab_object mm/kasan/common.c:247 [inline] __kasan_slab_free+0x59/0x70 mm/kasan/common.c:264 kasan_slab_free include/linux/kasan.h:230 [inline] slab_free_hook mm/slub.c:2343 [inline] slab_free mm/slub.c:4580 [inline] kfree+0x1a0/0x440 mm/slub.c:4728 generic_shutdown_super+0x13b/0x2d0 fs/super.c:642 kill_block_super+0x44/0x90 fs/super.c:1696 deactivate_locked_super+0xc6/0x130 fs/super.c:473 cleanup_mnt+0x41f/0x4b0 fs/namespace.c:1373 task_work_run+0x251/0x310 kernel/task_work.c:228 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline] exit_to_user_mode_loop kernel/entry/common.c:114 [inline] exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline] __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline] syscall_exit_to_user_mode+0x168/0x370 kernel/entry/common.c:218 do_syscall_64+0x100/0x230 arch/x86/entry/common.c:89 entry_SYSCALL_64_after_hwframe+0x77/0x7f The buggy address belongs to the object at ffff88804afbd200 which belongs to the cache kmalloc-256 of size 256 The buggy address is located 148 bytes inside of freed 256-byte region [ffff88804afbd200, ffff88804afbd300) The buggy address belongs to the physical page: page: refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x4afbc head: order:1 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0 flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff) page_type: f5(slab) raw: 00fff00000000040 ffff88801ac41b40 ffffea000134da80 dead000000000004 raw: 0000000000000000 0000000000100010 00000001f5000000 0000000000000000 head: 00fff00000000040 ffff88801ac41b40 ffffea000134da80 dead000000000004 head: 0000000000000000 0000000000100010 00000001f5000000 0000000000000000 head: 00fff00000000001 ffffea00012bef01 ffffffffffffffff 0000000000000000 head: 0000000000000002 0000000000000000 00000000ffffffff 0000000000000000 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 5232, tgid 5232 (syz-executor), ts 65557633803, free_ts 65549268276 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x1f3/0x230 mm/page_alloc.c:1537 prep_new_page mm/page_alloc.c:1545 [inline] get_page_from_freelist+0x3045/0x3190 mm/page_alloc.c:3457 __alloc_pages_noprof+0x256/0x6c0 mm/page_alloc.c:4733 alloc_pages_mpol_noprof+0x3e8/0x680 mm/mempolicy.c:2265 alloc_slab_page+0x6a/0x120 mm/slub.c:2413 allocate_slab+0x5a/0x2f0 mm/slub.c:2579 new_slab mm/slub.c:2632 [inline] ___slab_alloc+0xcd1/0x14b0 mm/slub.c:3819 __slab_alloc+0x58/0xa0 mm/slub.c:3909 __slab_alloc_node mm/slub.c:3962 [inline] slab_alloc_node mm/slub.c:4123 [inline] __do_kmalloc_node mm/slub.c:4264 [inline] __kmalloc_noprof+0x25a/0x400 mm/slub.c:4277 kmalloc_noprof include/linux/slab.h:882 [inline] kzalloc_noprof include/linux/slab.h:1014 [inline] fib_create_info+0xa49/0x24e0 net/ipv4/fib_semantics.c:1458 fib_table_insert+0x1f6/0x1f30 net/ipv4/fib_trie.c:1237 fib_magic+0x3d8/0x620 net/ipv4/fib_frontend.c:1104 fib_add_ifaddr+0x14c/0x5e0 net/ipv4/fib_frontend.c:1126 fib_netdev_event+0x375/0x490 net/ipv4/fib_frontend.c:1486 notifier_call_chain+0x1a1/0x3e0 kernel/notifier.c:93 __dev_notify_flags+0x207/0x400 page last free pid 24 tgid 24 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1108 [inline] free_unref_page+0xcfb/0xf20 mm/page_alloc.c:2638 rcu_do_batch kernel/rcu/tree.c:2567 [inline] rcu_core+0xaac/0x17a0 kernel/rcu/tree.c:2823 handle_softirqs+0x2c7/0x980 kernel/softirq.c:554 run_ksoftirqd+0xca/0x130 kernel/softirq.c:927 smpboot_thread_fn+0x546/0xa30 kernel/smpboot.c:164 kthread+0x2f2/0x390 kernel/kthread.c:389 ret_from_fork+0x4d/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 Memory state around the buggy address: ffff88804afbd180: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff88804afbd200: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff88804afbd280: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88804afbd300: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff88804afbd380: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ==================================================================