================================================================== BUG: KASAN: slab-use-after-free in jfs_lazycommit+0xa29/0xb20 fs/jfs/jfs_txnmgr.c:2736 Read of size 4 at addr ffff88805acfdc94 by task jfsCommit/137 CPU: 2 PID: 137 Comm: jfsCommit Not tainted 6.9.0-rc4-syzkaller-00274-g3b68086599f8 #0 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-debian-1.16.2-1 04/01/2014 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:114 print_address_description mm/kasan/report.c:377 [inline] print_report+0xc3/0x620 mm/kasan/report.c:488 kasan_report+0xd9/0x110 mm/kasan/report.c:601 jfs_lazycommit+0xa29/0xb20 fs/jfs/jfs_txnmgr.c:2736 kthread+0x2c1/0x3a0 kernel/kthread.c:388 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 Allocated by task 6217: kasan_save_stack+0x33/0x60 mm/kasan/common.c:47 kasan_save_track+0x14/0x30 mm/kasan/common.c:68 poison_kmalloc_redzone mm/kasan/common.c:370 [inline] __kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:387 kmalloc include/linux/slab.h:628 [inline] kzalloc include/linux/slab.h:749 [inline] jfs_fill_super+0xe5/0xd20 fs/jfs/super.c:495 mount_bdev+0x1e3/0x2d0 fs/super.c:1658 legacy_get_tree+0x109/0x220 fs/fs_context.c:662 vfs_get_tree+0x8f/0x380 fs/super.c:1779 do_new_mount fs/namespace.c:3352 [inline] path_mount+0x6e1/0x1f10 fs/namespace.c:3679 do_mount fs/namespace.c:3692 [inline] __do_sys_mount fs/namespace.c:3898 [inline] __se_sys_mount fs/namespace.c:3875 [inline] __ia32_sys_mount+0x295/0x320 fs/namespace.c:3875 do_syscall_32_irqs_on arch/x86/entry/common.c:165 [inline] __do_fast_syscall_32+0x75/0x120 arch/x86/entry/common.c:386 do_fast_syscall_32+0x32/0x80 arch/x86/entry/common.c:411 entry_SYSENTER_compat_after_hwframe+0x84/0x8e Freed by task 5211: kasan_save_stack+0x33/0x60 mm/kasan/common.c:47 kasan_save_track+0x14/0x30 mm/kasan/common.c:68 kasan_save_free_info+0x3b/0x60 mm/kasan/generic.c:579 poison_slab_object mm/kasan/common.c:240 [inline] __kasan_slab_free+0x11d/0x1a0 mm/kasan/common.c:256 kasan_slab_free include/linux/kasan.h:184 [inline] slab_free_hook mm/slub.c:2106 [inline] slab_free mm/slub.c:4280 [inline] kfree+0x129/0x390 mm/slub.c:4390 generic_shutdown_super+0x159/0x3d0 fs/super.c:641 kill_block_super+0x3b/0x90 fs/super.c:1675 deactivate_locked_super+0xbe/0x1a0 fs/super.c:472 deactivate_super+0xde/0x100 fs/super.c:505 cleanup_mnt+0x222/0x450 fs/namespace.c:1267 task_work_run+0x14e/0x250 kernel/task_work.c:180 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+0x278/0x2a0 kernel/entry/common.c:218 __do_fast_syscall_32+0x82/0x120 arch/x86/entry/common.c:389 do_fast_syscall_32+0x32/0x80 arch/x86/entry/common.c:411 entry_SYSENTER_compat_after_hwframe+0x84/0x8e The buggy address belongs to the object at ffff88805acfdc00 which belongs to the cache kmalloc-256 of size 256 The buggy address is located 148 bytes inside of freed 256-byte region [ffff88805acfdc00, ffff88805acfdd00) The buggy address belongs to the physical page: page: refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x5acfc head: order:1 entire_mapcount:0 nr_pages_mapped:0 pincount:0 anon flags: 0x4fff80000000840(slab|head|node=1|zone=1|lastcpupid=0xfff) page_type: 0xffffffff() raw: 04fff80000000840 ffff888014c42b40 ffffea00017a3d80 dead000000000005 raw: 0000000000000000 0000000080100010 00000001ffffffff 0000000000000000 head: 04fff80000000840 ffff888014c42b40 ffffea00017a3d80 dead000000000005 head: 0000000000000000 0000000080100010 00000001ffffffff 0000000000000000 head: 04fff80000000001 ffffea00016b3f01 dead000000000122 00000000ffffffff head: 0000000200000000 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 5213, tgid 1328124219 (syz-executor.0), ts 5213, free_ts 0 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x2d4/0x350 mm/page_alloc.c:1534 prep_new_page mm/page_alloc.c:1541 [inline] get_page_from_freelist+0xa28/0x3780 mm/page_alloc.c:3317 __alloc_pages+0x22b/0x2460 mm/page_alloc.c:4575 __alloc_pages_node include/linux/gfp.h:238 [inline] alloc_pages_node include/linux/gfp.h:261 [inline] alloc_slab_page mm/slub.c:2175 [inline] allocate_slab mm/slub.c:2338 [inline] new_slab+0xcc/0x3a0 mm/slub.c:2391 ___slab_alloc+0x670/0x16d0 mm/slub.c:3525 __slab_alloc.constprop.0+0x56/0xb0 mm/slub.c:3610 __slab_alloc_node mm/slub.c:3663 [inline] slab_alloc_node mm/slub.c:3835 [inline] __do_kmalloc_node mm/slub.c:3965 [inline] __kmalloc+0x3b4/0x440 mm/slub.c:3979 kmalloc include/linux/slab.h:632 [inline] kzalloc include/linux/slab.h:749 [inline] fib_create_info+0x852/0x4d30 net/ipv4/fib_semantics.c:1459 fib_table_insert+0x1d7/0x1d70 net/ipv4/fib_trie.c:1237 fib_magic+0x4d6/0x5c0 net/ipv4/fib_frontend.c:1109 fib_add_ifaddr+0x4c0/0x560 net/ipv4/fib_frontend.c:1153 fib_netdev_event+0x38d/0x710 net/ipv4/fib_frontend.c:1491 notifier_call_chain+0xb9/0x410 kernel/notifier.c:93 call_netdevice_notifiers_info+0xbe/0x140 net/core/dev.c:1950 call_netdevice_notifiers_extack net/core/dev.c:1988 [inline] call_netdevice_notifiers net/core/dev.c:2002 [inline] __dev_notify_flags+0x12d/0x2e0 net/core/dev.c:8731 dev_change_flags+0x10c/0x160 net/core/dev.c:8769 page_owner free stack trace missing Memory state around the buggy address: ffff88805acfdb80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff88805acfdc00: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff88805acfdc80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88805acfdd00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff88805acfdd80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ==================================================================