audit: type=1400 audit(1521133204.939:7): avc: denied { map } for pid=4096 comm="syzkaller144721" path="/root/syzkaller144721791" dev="sda1" ino=16481 scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=unconfined_u:object_r:user_home_t:s0 tclass=file permissive=1 ================================================================== BUG: KASAN: use-after-free in __list_del_entry_valid+0x144/0x150 lib/list_debug.c:54 Read of size 8 at addr ffff8801d2435ce0 by task syzkaller144721/4121 CPU: 0 PID: 4121 Comm: syzkaller144721 Not tainted 4.16.0-rc5+ #354 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:17 [inline] dump_stack+0x194/0x24d lib/dump_stack.c:53 print_address_description+0x73/0x250 mm/kasan/report.c:256 kasan_report_error mm/kasan/report.c:354 [inline] kasan_report+0x23c/0x360 mm/kasan/report.c:412 __asan_report_load8_noabort+0x14/0x20 mm/kasan/report.c:433 __list_del_entry_valid+0x144/0x150 lib/list_debug.c:54 __list_del_entry include/linux/list.h:117 [inline] list_del include/linux/list.h:125 [inline] cma_cancel_listens drivers/infiniband/core/cma.c:1569 [inline] cma_cancel_operation+0x455/0xd60 drivers/infiniband/core/cma.c:1597 rdma_destroy_id+0xff/0xda0 drivers/infiniband/core/cma.c:1661 ucma_close+0x100/0x2f0 drivers/infiniband/core/ucma.c:1712 __fput+0x327/0x7e0 fs/file_table.c:209 ____fput+0x15/0x20 fs/file_table.c:243 task_work_run+0x199/0x270 kernel/task_work.c:113 exit_task_work include/linux/task_work.h:22 [inline] do_exit+0x9bb/0x1ad0 kernel/exit.c:865 do_group_exit+0x149/0x400 kernel/exit.c:968 get_signal+0x73a/0x16d0 kernel/signal.c:2469 do_signal+0x90/0x1e90 arch/x86/kernel/signal.c:809 exit_to_usermode_loop+0x258/0x2f0 arch/x86/entry/common.c:162 prepare_exit_to_usermode arch/x86/entry/common.c:196 [inline] syscall_return_slowpath arch/x86/entry/common.c:265 [inline] do_syscall_64+0x6ec/0x940 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x42/0xb7 RIP: 0033:0x446af9 RSP: 002b:00007fc143953da8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca RAX: fffffffffffffe00 RBX: 00000000006e29fc RCX: 0000000000446af9 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 00000000006e29fc RBP: 00000000006e29f8 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 006d635f616d6472 R13: 2f646e6162696e69 R14: 666e692f7665642f R15: 0000000000000005 Allocated by task 4121: save_stack+0x43/0xd0 mm/kasan/kasan.c:447 set_track mm/kasan/kasan.c:459 [inline] kasan_kmalloc+0xad/0xe0 mm/kasan/kasan.c:552 kmem_cache_alloc_trace+0x136/0x740 mm/slab.c:3607 kmalloc include/linux/slab.h:512 [inline] kzalloc include/linux/slab.h:701 [inline] rdma_create_id+0xd0/0x630 drivers/infiniband/core/cma.c:787 ucma_create_id+0x31a/0x620 drivers/infiniband/core/ucma.c:479 ucma_write+0x2d6/0x3d0 drivers/infiniband/core/ucma.c:1633 __vfs_write+0xef/0x970 fs/read_write.c:480 vfs_write+0x189/0x510 fs/read_write.c:544 SYSC_write fs/read_write.c:589 [inline] SyS_write+0xef/0x220 fs/read_write.c:581 do_syscall_64+0x281/0x940 arch/x86/entry/common.c:287 entry_SYSCALL_64_after_hwframe+0x42/0xb7 Freed by task 4121: save_stack+0x43/0xd0 mm/kasan/kasan.c:447 set_track mm/kasan/kasan.c:459 [inline] __kasan_slab_free+0x11a/0x170 mm/kasan/kasan.c:520 kasan_slab_free+0xe/0x10 mm/kasan/kasan.c:527 __cache_free mm/slab.c:3485 [inline] kfree+0xd9/0x260 mm/slab.c:3800 rdma_destroy_id+0x821/0xda0 drivers/infiniband/core/cma.c:1691 ucma_close+0x100/0x2f0 drivers/infiniband/core/ucma.c:1712 __fput+0x327/0x7e0 fs/file_table.c:209 ____fput+0x15/0x20 fs/file_table.c:243 task_work_run+0x199/0x270 kernel/task_work.c:113 exit_task_work include/linux/task_work.h:22 [inline] do_exit+0x9bb/0x1ad0 kernel/exit.c:865 do_group_exit+0x149/0x400 kernel/exit.c:968 get_signal+0x73a/0x16d0 kernel/signal.c:2469 do_signal+0x90/0x1e90 arch/x86/kernel/signal.c:809 exit_to_usermode_loop+0x258/0x2f0 arch/x86/entry/common.c:162 prepare_exit_to_usermode arch/x86/entry/common.c:196 [inline] syscall_return_slowpath arch/x86/entry/common.c:265 [inline] do_syscall_64+0x6ec/0x940 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x42/0xb7 The buggy address belongs to the object at ffff8801d2435b00 which belongs to the cache kmalloc-1024 of size 1024 The buggy address is located 480 bytes inside of 1024-byte region [ffff8801d2435b00, ffff8801d2435f00) The buggy address belongs to the page: page:ffffea0007490d00 count:1 mapcount:0 mapping:ffff8801d2434000 index:0x0 compound_mapcount: 0 flags: 0x2fffc0000008100(slab|head) raw: 02fffc0000008100 ffff8801d2434000 0000000000000000 0000000100000007 raw: ffffea000730eb20 ffff8801dac01848 ffff8801dac00ac0 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff8801d2435b80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8801d2435c00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff8801d2435c80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff8801d2435d00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8801d2435d80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================