bridge0: port 3(gretap0) entered disabled state device gretap0 entered promiscuous mode bridge0: port 3(gretap0) entered blocking state bridge0: port 3(gretap0) entered forwarding state ================================================================== BUG: KASAN: use-after-free in atomic_dec_and_test include/asm-generic/atomic-instrumented.h:259 [inline] BUG: KASAN: use-after-free in put_task_struct include/linux/sched/task.h:95 [inline] BUG: KASAN: use-after-free in rdma_restrack_del+0x86/0x240 drivers/infiniband/core/restrack.c:229 Write of size 4 at addr ffff888059712020 by task syz-executor.2/9491 CPU: 1 PID: 9491 Comm: syz-executor.2 Not tainted 4.19.75 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x172/0x1f0 lib/dump_stack.c:113 print_address_description.cold+0x7c/0x20d mm/kasan/report.c:256 kasan_report_error mm/kasan/report.c:354 [inline] kasan_report mm/kasan/report.c:412 [inline] kasan_report.cold+0x8c/0x2ba mm/kasan/report.c:396 check_memory_region_inline mm/kasan/kasan.c:260 [inline] check_memory_region+0x123/0x190 mm/kasan/kasan.c:267 kasan_check_write+0x14/0x20 mm/kasan/kasan.c:278 atomic_dec_and_test include/asm-generic/atomic-instrumented.h:259 [inline] put_task_struct include/linux/sched/task.h:95 [inline] rdma_restrack_del+0x86/0x240 drivers/infiniband/core/restrack.c:229 rdma_destroy_id+0xac/0xab0 drivers/infiniband/core/cma.c:1726 ucma_close+0x115/0x320 drivers/infiniband/core/ucma.c:1770 __fput+0x2dd/0x8b0 fs/file_table.c:278 ____fput+0x16/0x20 fs/file_table.c:309 task_work_run+0x145/0x1c0 kernel/task_work.c:113 exit_task_work include/linux/task_work.h:22 [inline] do_exit+0x994/0x2fa0 kernel/exit.c:876 do_group_exit+0x135/0x370 kernel/exit.c:979 get_signal+0x3ec/0x1fc0 kernel/signal.c:2574 do_signal+0x95/0x1960 arch/x86/kernel/signal.c:821 exit_to_usermode_loop+0x244/0x2c0 arch/x86/entry/common.c:163 prepare_exit_to_usermode arch/x86/entry/common.c:198 [inline] syscall_return_slowpath arch/x86/entry/common.c:271 [inline] do_syscall_64+0x53d/0x620 arch/x86/entry/common.c:296 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x459a29 Code: cc 48 8b 74 24 08 48 8b 5c 24 10 8a 44 24 18 4c 8d 44 24 20 e9 08 00 00 00 cc cc cc cc cc cc cc cc 66 48 0f 6e c0 66 0f 60 c0 <66> 0f 60 c0 66 0f 70 c0 00 48 83 fb 10 7c 6e 49 c7 c4 00 00 00 00 RSP: 002b:00007fceaf427cf8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca RAX: fffffffffffffe00 RBX: 000000000075c078 RCX: 0000000000459a29 RDX: 0000000000000000 RSI: 0000000000000080 RDI: 000000000075c078 RBP: 000000000075c070 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000075c07c R13: 00007ffc4d9a75df R14: 00007fceaf4289c0 R15: 000000000075c07c Allocated by task 9478: save_stack+0x45/0xd0 mm/kasan/kasan.c:448 set_track mm/kasan/kasan.c:460 [inline] kasan_kmalloc mm/kasan/kasan.c:553 [inline] kasan_kmalloc+0xce/0xf0 mm/kasan/kasan.c:531 kasan_slab_alloc+0xf/0x20 mm/kasan/kasan.c:490 kmem_cache_alloc_node+0x144/0x710 mm/slab.c:3649 alloc_task_struct_node kernel/fork.c:157 [inline] dup_task_struct kernel/fork.c:802 [inline] copy_process.part.0+0x1ce0/0x7a30 kernel/fork.c:1732 copy_process kernel/fork.c:1689 [inline] _do_fork+0x257/0xfd0 kernel/fork.c:2202 __do_sys_clone kernel/fork.c:2309 [inline] __se_sys_clone kernel/fork.c:2303 [inline] __x64_sys_clone+0xbf/0x150 kernel/fork.c:2303 do_syscall_64+0xfd/0x620 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe Freed by task 9491: save_stack+0x45/0xd0 mm/kasan/kasan.c:448 set_track mm/kasan/kasan.c:460 [inline] __kasan_slab_free+0x102/0x150 mm/kasan/kasan.c:521 kasan_slab_free+0xe/0x10 mm/kasan/kasan.c:528 __cache_free mm/slab.c:3503 [inline] kmem_cache_free+0x86/0x260 mm/slab.c:3765 free_task_struct kernel/fork.c:162 [inline] free_task+0xdd/0x120 kernel/fork.c:416 __put_task_struct+0x20f/0x4c0 kernel/fork.c:689 put_task_struct include/linux/sched/task.h:96 [inline] _free_event+0xc76/0x1220 kernel/events/core.c:4460 put_event+0x47/0x60 kernel/events/core.c:4547 perf_event_release_kernel+0x6d1/0xd80 kernel/events/core.c:4662 perf_release+0x37/0x50 kernel/events/core.c:4672 __fput+0x2dd/0x8b0 fs/file_table.c:278 ____fput+0x16/0x20 fs/file_table.c:309 task_work_run+0x145/0x1c0 kernel/task_work.c:113 exit_task_work include/linux/task_work.h:22 [inline] do_exit+0x994/0x2fa0 kernel/exit.c:876 do_group_exit+0x135/0x370 kernel/exit.c:979 get_signal+0x3ec/0x1fc0 kernel/signal.c:2574 do_signal+0x95/0x1960 arch/x86/kernel/signal.c:821 exit_to_usermode_loop+0x244/0x2c0 arch/x86/entry/common.c:163 prepare_exit_to_usermode arch/x86/entry/common.c:198 [inline] syscall_return_slowpath arch/x86/entry/common.c:271 [inline] do_syscall_64+0x53d/0x620 arch/x86/entry/common.c:296 entry_SYSCALL_64_after_hwframe+0x49/0xbe The buggy address belongs to the object at ffff888059712000 which belongs to the cache task_struct(49:syz2) of size 6080 The buggy address is located 32 bytes inside of 6080-byte region [ffff888059712000, ffff8880597137c0) The buggy address belongs to the page: page:ffffea000165c480 count:1 mapcount:0 mapping:ffff8880a58d1500 index:0x0 compound_mapcount: 0 flags: 0x1fffc0000008100(slab|head) raw: 01fffc0000008100 ffffea000135cc08 ffffea000155a508 ffff8880a58d1500 raw: 0000000000000000 ffff888059712000 0000000100000001 ffff8880581cc4c0 page dumped because: kasan: bad access detected page->mem_cgroup:ffff8880581cc4c0 Memory state around the buggy address: ffff888059711f00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff888059711f80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff888059712000: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff888059712080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888059712100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================