================================================================== BUG: KASAN: use-after-free in instrument_atomic_read_write include/linux/instrumented.h:101 [inline] BUG: KASAN: use-after-free in atomic_dec_return include/asm-generic/atomic-instrumented.h:340 [inline] BUG: KASAN: use-after-free in rxrpc_put_bundle+0x1d/0x80 net/rxrpc/conn_client.c:141 Write of size 4 at addr ffff8880a8fcce20 by task syz-executor.0/19185 CPU: 0 PID: 19185 Comm: syz-executor.0 Not tainted 5.9.0-rc8-next-20201006-syzkaller #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+0x198/0x1fb lib/dump_stack.c:118 print_address_description.constprop.0.cold+0xae/0x497 mm/kasan/report.c:385 __kasan_report mm/kasan/report.c:545 [inline] kasan_report.cold+0x1f/0x37 mm/kasan/report.c:562 check_memory_region_inline mm/kasan/generic.c:186 [inline] check_memory_region+0x13d/0x180 mm/kasan/generic.c:192 instrument_atomic_read_write include/linux/instrumented.h:101 [inline] atomic_dec_return include/asm-generic/atomic-instrumented.h:340 [inline] rxrpc_put_bundle+0x1d/0x80 net/rxrpc/conn_client.c:141 rxrpc_destroy_connection+0x150/0x2f0 net/rxrpc/conn_object.c:367 rcu_do_batch kernel/rcu/tree.c:2484 [inline] rcu_core+0x645/0x1240 kernel/rcu/tree.c:2718 __do_softirq+0x203/0xab6 kernel/softirq.c:298 asm_call_irq_on_stack+0xf/0x20 __run_on_irqstack arch/x86/include/asm/irq_stack.h:26 [inline] run_on_irqstack_cond arch/x86/include/asm/irq_stack.h:77 [inline] do_softirq_own_stack+0x9b/0xd0 arch/x86/kernel/irq_64.c:77 invoke_softirq kernel/softirq.c:393 [inline] __irq_exit_rcu kernel/softirq.c:423 [inline] irq_exit_rcu+0x235/0x280 kernel/softirq.c:435 sysvec_apic_timer_interrupt+0x51/0xf0 arch/x86/kernel/apic/apic.c:1091 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:631 RIP: 0010:zap_pte_range mm/memory.c:1251 [inline] RIP: 0010:zap_pmd_range mm/memory.c:1392 [inline] RIP: 0010:zap_pud_range mm/memory.c:1421 [inline] RIP: 0010:zap_p4d_range mm/memory.c:1442 [inline] RIP: 0010:unmap_page_range+0xb23/0x2b50 mm/memory.c:1463 Code: 00 00 c7 84 24 bc 00 00 00 00 00 00 00 4c 8b 6c 24 28 49 81 c5 00 10 00 00 49 8d 85 00 f0 ff ff 48 89 44 24 28 e8 0d 41 ce ff <48> 8b 44 24 08 48 c1 e8 03 42 80 3c 30 00 0f 85 37 1a 00 00 48 8b RSP: 0018:ffffc90007257790 EFLAGS: 00000293 RAX: 0000000000000000 RBX: 00007fd9b2f98000 RCX: ffffffff81a70b4a RDX: ffff888048c90300 RSI: ffffffff81a70623 RDI: 0000000000000006 RBP: ffffea0002568d00 R08: 0000000000000000 R09: ffffea0002568d33 R10: 00007fd9b2f98000 R11: 0000000000000000 R12: ffffea0002568d30 R13: 00007fd9b2ee9000 R14: dffffc0000000000 R15: ffffea0002568d08 unmap_single_vma+0x198/0x300 mm/memory.c:1508 unmap_vmas+0x168/0x2e0 mm/memory.c:1540 exit_mmap+0x2b1/0x530 mm/mmap.c:3233 __mmput+0x122/0x470 kernel/fork.c:1077 mmput+0x53/0x60 kernel/fork.c:1098 exit_mm kernel/exit.c:483 [inline] do_exit+0xa31/0x2930 kernel/exit.c:793 do_group_exit+0x125/0x310 kernel/exit.c:903 get_signal+0x428/0x1f00 kernel/signal.c:2757 arch_do_signal+0x82/0x2470 arch/x86/kernel/signal.c:811 exit_to_user_mode_loop kernel/entry/common.c:161 [inline] exit_to_user_mode_prepare+0x194/0x1f0 kernel/entry/common.c:192 syscall_exit_to_user_mode+0x7a/0x2c0 kernel/entry/common.c:267 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x45de29 Code: Unable to access opcode bytes at RIP 0x45ddff. RSP: 002b:00007fd9b2395cf8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca RAX: fffffffffffffe00 RBX: 000000000118bf28 RCX: 000000000045de29 RDX: 0000000000000000 RSI: 0000000000000080 RDI: 000000000118bf28 RBP: 000000000118bf20 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000118bf2c R13: 00007ffc067a60bf R14: 00007fd9b23969c0 R15: 000000000118bf2c Allocated by task 19186: kasan_save_stack+0x1b/0x40 mm/kasan/common.c:48 kasan_set_track mm/kasan/common.c:56 [inline] __kasan_kmalloc.constprop.0+0xbf/0xd0 mm/kasan/common.c:461 kmem_cache_alloc_trace+0x1a0/0x480 mm/slab.c:3552 kmalloc include/linux/slab.h:554 [inline] kzalloc include/linux/slab.h:666 [inline] rxrpc_alloc_bundle+0x88/0x2c0 net/rxrpc/conn_client.c:121 rxrpc_look_up_bundle net/rxrpc/conn_client.c:275 [inline] rxrpc_prep_call net/rxrpc/conn_client.c:374 [inline] rxrpc_connect_call+0x85c/0x1580 net/rxrpc/conn_client.c:710 rxrpc_new_client_call+0x961/0x1020 net/rxrpc/call_object.c:331 rxrpc_new_client_call_for_sendmsg net/rxrpc/sendmsg.c:622 [inline] rxrpc_do_sendmsg+0xf14/0x1370 net/rxrpc/sendmsg.c:679 rxrpc_sendmsg+0x420/0x630 net/rxrpc/af_rxrpc.c:560 sock_sendmsg_nosec net/socket.c:651 [inline] sock_sendmsg+0xcf/0x120 net/socket.c:671 ____sys_sendmsg+0x6e8/0x810 net/socket.c:2362 ___sys_sendmsg+0xf3/0x170 net/socket.c:2416 __sys_sendmsg+0xe5/0x1b0 net/socket.c:2449 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xa9 Freed by task 7152: kasan_save_stack+0x1b/0x40 mm/kasan/common.c:48 kasan_set_track+0x1c/0x30 mm/kasan/common.c:56 kasan_set_free_info+0x1b/0x30 mm/kasan/generic.c:355 __kasan_slab_free+0xd8/0x120 mm/kasan/common.c:422 __cache_free mm/slab.c:3420 [inline] kfree+0x10e/0x2a0 mm/slab.c:3758 rxrpc_put_bundle net/rxrpc/conn_client.c:146 [inline] rxrpc_put_bundle+0x6b/0x80 net/rxrpc/conn_client.c:138 rxrpc_unbundle_conn+0x1f8/0x3d0 net/rxrpc/conn_client.c:935 rxrpc_clean_up_local_conns+0x38d/0x590 net/rxrpc/conn_client.c:1114 rxrpc_local_destroyer net/rxrpc/local_object.c:399 [inline] rxrpc_local_processor+0x38d/0x5e0 net/rxrpc/local_object.c:433 process_one_work+0x933/0x15a0 kernel/workqueue.c:2269 worker_thread+0x64c/0x1120 kernel/workqueue.c:2415 kthread+0x3af/0x4a0 kernel/kthread.c:292 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:296 The buggy address belongs to the object at ffff8880a8fcce00 which belongs to the cache kmalloc-192 of size 192 The buggy address is located 32 bytes inside of 192-byte region [ffff8880a8fcce00, ffff8880a8fccec0) The buggy address belongs to the page: page:0000000017f63074 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0xa8fcc flags: 0xfffe0000000200(slab) raw: 00fffe0000000200 ffffea00028309c8 ffffea0002495308 ffff8880aa040000 raw: 0000000000000000 ffff8880a8fcc000 0000000100000010 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff8880a8fccd00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff8880a8fccd80: 00 00 fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff8880a8fcce00: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff8880a8fcce80: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc ffff8880a8fccf00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ==================================================================