IPv6: ADDRCONF(NETDEV_CHANGE): veth1_to_batadv: link becomes ready audit: type=1400 audit(1582716278.347:41): avc: denied { associate } for pid=8171 comm="syz-executor.0" name="syz0" scontext=unconfined_u:object_r:unlabeled_t:s0 tcontext=system_u:object_r:unlabeled_t:s0 tclass=filesystem permissive=1 ================================================================== BUG: KASAN: use-after-free in __list_add_valid+0x9a/0xa0 lib/list_debug.c:26 Read of size 8 at addr ffff888094b4d360 by task syz-executor.0/8231 CPU: 1 PID: 8231 Comm: syz-executor.0 Not tainted 4.19.106-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+0x197/0x210 lib/dump_stack.c:118 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 __asan_report_load8_noabort+0x14/0x20 mm/kasan/report.c:433 __list_add_valid+0x9a/0xa0 lib/list_debug.c:26 __list_add include/linux/list.h:60 [inline] list_add_tail include/linux/list.h:93 [inline] cma_listen_on_all drivers/infiniband/core/cma.c:2380 [inline] rdma_listen+0x63b/0x8e0 drivers/infiniband/core/cma.c:3408 ucma_listen+0x14d/0x1c0 drivers/infiniband/core/ucma.c:1100 ucma_write+0x2d7/0x3c0 drivers/infiniband/core/ucma.c:1689 __vfs_write+0x114/0x810 fs/read_write.c:485 vfs_write+0x20c/0x560 fs/read_write.c:549 ksys_write+0x14f/0x2d0 fs/read_write.c:599 __do_sys_write fs/read_write.c:611 [inline] __se_sys_write fs/read_write.c:608 [inline] __x64_sys_write+0x73/0xb0 fs/read_write.c:608 do_syscall_64+0xfd/0x620 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x45c449 Code: ad b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 7b b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007f071bd0fc78 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 00007f071bd106d4 RCX: 000000000045c449 RDX: 0000000000000010 RSI: 0000000020000140 RDI: 0000000000000003 RBP: 000000000076bf20 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff R13: 0000000000000cbe R14: 00000000004cea14 R15: 000000000076bf2c Allocated by task 8225: 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 kmem_cache_alloc_trace+0x152/0x760 mm/slab.c:3625 kmalloc include/linux/slab.h:515 [inline] kzalloc include/linux/slab.h:709 [inline] __rdma_create_id+0x5e/0x610 drivers/infiniband/core/cma.c:784 ucma_create_id+0x1de/0x640 drivers/infiniband/core/ucma.c:506 ucma_write+0x2d7/0x3c0 drivers/infiniband/core/ucma.c:1689 __vfs_write+0x114/0x810 fs/read_write.c:485 vfs_write+0x20c/0x560 fs/read_write.c:549 ksys_write+0x14f/0x2d0 fs/read_write.c:599 __do_sys_write fs/read_write.c:611 [inline] __se_sys_write fs/read_write.c:608 [inline] __x64_sys_write+0x73/0xb0 fs/read_write.c:608 do_syscall_64+0xfd/0x620 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe Freed by task 8225: 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] kfree+0xcf/0x220 mm/slab.c:3822 rdma_destroy_id+0x726/0xab0 drivers/infiniband/core/cma.c:1752 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 tracehook_notify_resume include/linux/tracehook.h:193 [inline] exit_to_usermode_loop+0x273/0x2c0 arch/x86/entry/common.c:167 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 ffff888094b4d180 which belongs to the cache kmalloc-2048 of size 2048 The buggy address is located 480 bytes inside of 2048-byte region [ffff888094b4d180, ffff888094b4d980) The buggy address belongs to the page: page:ffffea000252d300 count:1 mapcount:0 mapping:ffff88812c31cc40 index:0x0 compound_mapcount: 0 flags: 0xfffe0000008100(slab|head) raw: 00fffe0000008100 ffffea00024e6788 ffffea0002254808 ffff88812c31cc40 raw: 0000000000000000 ffff888094b4c080 0000000100000003 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff888094b4d200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888094b4d280: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff888094b4d300: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff888094b4d380: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888094b4d400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================