================================================================== BUG: KASAN: use-after-free in atomic64_try_cmpxchg include/asm-generic/atomic-instrumented.h:1503 [inline] BUG: KASAN: use-after-free in atomic_long_try_cmpxchg_acquire include/asm-generic/atomic-long.h:442 [inline] BUG: KASAN: use-after-free in __down_read_trylock kernel/locking/rwsem.c:1408 [inline] BUG: KASAN: use-after-free in down_read_trylock+0xba/0x1d0 kernel/locking/rwsem.c:1568 Write of size 8 at addr ffff8881aecce070 by task kworker/u4:3/363 CPU: 1 PID: 363 Comm: kworker/u4:3 Not tainted 5.4.225-syzkaller-00007-g250ac66f1853 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/02/2023 Workqueue: writeback wb_workfn (flush-7:2) Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x1d8/0x241 lib/dump_stack.c:118 print_address_description+0x8c/0x600 mm/kasan/report.c:384 __kasan_report+0xf3/0x120 mm/kasan/report.c:516 kasan_report+0x30/0x60 mm/kasan/common.c:653 check_memory_region_inline mm/kasan/generic.c:141 [inline] check_memory_region+0x272/0x280 mm/kasan/generic.c:191 atomic64_try_cmpxchg include/asm-generic/atomic-instrumented.h:1503 [inline] atomic_long_try_cmpxchg_acquire include/asm-generic/atomic-long.h:442 [inline] __down_read_trylock kernel/locking/rwsem.c:1408 [inline] down_read_trylock+0xba/0x1d0 kernel/locking/rwsem.c:1568 trylock_super+0x1b/0xf0 fs/super.c:418 __writeback_inodes_wb fs/fs-writeback.c:1792 [inline] wb_writeback+0x499/0xd70 fs/fs-writeback.c:1907 wb_check_start_all fs/fs-writeback.c:2031 [inline] wb_do_writeback fs/fs-writeback.c:2057 [inline] wb_workfn+0x860/0x10c0 fs/fs-writeback.c:2091 process_one_work+0x765/0xd20 kernel/workqueue.c:2287 worker_thread+0xaef/0x1470 kernel/workqueue.c:2433 kthread+0x2da/0x360 kernel/kthread.c:288 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:354 Allocated by task 16788: save_stack mm/kasan/common.c:70 [inline] set_track mm/kasan/common.c:78 [inline] __kasan_kmalloc+0x130/0x1d0 mm/kasan/common.c:529 kmalloc include/linux/slab.h:556 [inline] kzalloc include/linux/slab.h:690 [inline] alloc_super+0x56/0x760 fs/super.c:203 sget+0x1f1/0x4d0 fs/super.c:613 mount_bdev+0xe4/0x340 fs/super.c:1390 legacy_get_tree+0xdf/0x170 fs/fs_context.c:647 vfs_get_tree+0x85/0x260 fs/super.c:1547 do_new_mount+0x292/0x570 fs/namespace.c:2843 do_mount+0x688/0xdd0 fs/namespace.c:3163 ksys_mount+0xc2/0xf0 fs/namespace.c:3372 __do_sys_mount fs/namespace.c:3386 [inline] __se_sys_mount fs/namespace.c:3383 [inline] __x64_sys_mount+0xb1/0xc0 fs/namespace.c:3383 do_syscall_64+0xca/0x1c0 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x5c/0xc1 Freed by task 118: save_stack mm/kasan/common.c:70 [inline] set_track mm/kasan/common.c:78 [inline] kasan_set_free_info mm/kasan/common.c:345 [inline] __kasan_slab_free+0x178/0x230 mm/kasan/common.c:487 slab_free_hook mm/slub.c:1455 [inline] slab_free_freelist_hook mm/slub.c:1494 [inline] slab_free mm/slub.c:3080 [inline] kfree+0xeb/0x320 mm/slub.c:4071 process_one_work+0x765/0xd20 kernel/workqueue.c:2287 worker_thread+0xaef/0x1470 kernel/workqueue.c:2433 kthread+0x2da/0x360 kernel/kthread.c:288 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:354 The buggy address belongs to the object at ffff8881aecce000 which belongs to the cache kmalloc-2k of size 2048 The buggy address is located 112 bytes inside of 2048-byte region [ffff8881aecce000, ffff8881aecce800) The buggy address belongs to the page: page:ffffea0006bb3200 refcount:1 mapcount:0 mapping:ffff8881f5c0c000 index:0xffff8881aeccb000 compound_mapcount: 0 flags: 0x8000000000010200(slab|head) raw: 8000000000010200 ffffea0007855208 ffffea0007ae3008 ffff8881f5c0c000 raw: ffff8881aeccb000 0000000000080006 00000001ffffffff 0000000000000000 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 3, migratetype Unmovable, gfp_mask 0xd2a20(GFP_ATOMIC|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC) set_page_owner include/linux/page_owner.h:31 [inline] post_alloc_hook mm/page_alloc.c:2165 [inline] prep_new_page+0x18f/0x370 mm/page_alloc.c:2171 get_page_from_freelist+0x2ce8/0x2d70 mm/page_alloc.c:3794 __alloc_pages_nodemask+0x393/0x840 mm/page_alloc.c:4891 alloc_slab_page+0x39/0x3c0 mm/slub.c:343 allocate_slab mm/slub.c:1683 [inline] new_slab+0x97/0x440 mm/slub.c:1749 new_slab_objects mm/slub.c:2505 [inline] ___slab_alloc+0x2fe/0x490 mm/slub.c:2667 __slab_alloc+0x5a/0x90 mm/slub.c:2707 slab_alloc_node mm/slub.c:2792 [inline] slab_alloc mm/slub.c:2837 [inline] __kmalloc_track_caller+0x168/0x290 mm/slub.c:4449 __kmalloc_reserve net/core/skbuff.c:142 [inline] __alloc_skb+0xb4/0x4d0 net/core/skbuff.c:210 alloc_skb include/linux/skbuff.h:1079 [inline] igmpv3_newpack+0x156/0x1030 net/ipv4/igmp.c:361 add_grhead+0x75/0x2c0 net/ipv4/igmp.c:442 add_grec+0x12c9/0x15d0 net/ipv4/igmp.c:576 igmpv3_send_cr net/ipv4/igmp.c:713 [inline] igmp_ifc_timer_expire+0x7bc/0xea0 net/ipv4/igmp.c:811 call_timer_fn+0x36/0x390 kernel/time/timer.c:1418 expire_timers kernel/time/timer.c:1463 [inline] __run_timers+0x7c2/0xae0 kernel/time/timer.c:1787 run_timer_softirq+0x46/0x80 kernel/time/timer.c:1800 page_owner free stack trace missing Memory state around the buggy address: ffff8881aeccdf00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff8881aeccdf80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff8881aecce000: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff8881aecce080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8881aecce100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ================================================================== device bridge_slave_1 left promiscuous mode bridge0: port 2(bridge_slave_1) entered disabled state device bridge_slave_0 left promiscuous mode bridge0: port 1(bridge_slave_0) entered disabled state