audit: type=1400 audit(1520709421.439:11370): avc: denied { map } for pid=24983 comm="sh" path="/bin/dash" dev="sda1" ino=1473 scontext=system_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=system_u:object_r:file_t:s0 tclass=file permissive=1 bond0 (unregistering): Released all slaves ================================================================== BUG: KASAN: use-after-free in __read_once_size include/linux/compiler.h:188 [inline] BUG: KASAN: use-after-free in atomic_read arch/x86/include/asm/atomic.h:27 [inline] BUG: KASAN: use-after-free in refcount_read include/linux/refcount.h:42 [inline] BUG: KASAN: use-after-free in check_net include/net/net_namespace.h:228 [inline] BUG: KASAN: use-after-free in rds_destroy_pending net/rds/rds.h:868 [inline] BUG: KASAN: use-after-free in rds_queue_reconnect+0x89f/0x970 net/rds/threads.c:152 Read of size 4 at addr ffff8801b1cca184 by task kworker/u4:10/18494 CPU: 1 PID: 18494 Comm: kworker/u4:10 Not tainted 4.16.0-rc4+ #258 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: krdsd rds_connect_worker 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_load4_noabort+0x14/0x20 mm/kasan/report.c:432 __read_once_size include/linux/compiler.h:188 [inline] atomic_read arch/x86/include/asm/atomic.h:27 [inline] refcount_read include/linux/refcount.h:42 [inline] check_net include/net/net_namespace.h:228 [inline] rds_destroy_pending net/rds/rds.h:868 [inline] rds_queue_reconnect+0x89f/0x970 net/rds/threads.c:152 rds_connect_worker+0x1a2/0x1f0 net/rds/threads.c:183 process_one_work+0xc47/0x1bb0 kernel/workqueue.c:2113 worker_thread+0x223/0x1990 kernel/workqueue.c:2247 IPVS: ftp: loaded support on port[0] = 21 kthread+0x33c/0x400 kernel/kthread.c:238 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:406 Allocated by task 4230: 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 kasan_slab_alloc+0x12/0x20 mm/kasan/kasan.c:489 kmem_cache_alloc+0x12e/0x760 mm/slab.c:3541 kmem_cache_zalloc include/linux/slab.h:691 [inline] net_alloc net/core/net_namespace.c:369 [inline] copy_net_ns+0x152/0x580 net/core/net_namespace.c:409 create_new_namespaces+0x425/0x880 kernel/nsproxy.c:107 unshare_nsproxy_namespaces+0xae/0x1e0 kernel/nsproxy.c:206 SYSC_unshare kernel/fork.c:2407 [inline] SyS_unshare+0x653/0xfa0 kernel/fork.c:2357 do_syscall_32_irqs_on arch/x86/entry/common.c:330 [inline] do_fast_syscall_32+0x3ec/0xf9f arch/x86/entry/common.c:392 entry_SYSENTER_compat+0x70/0x7f arch/x86/entry/entry_64_compat.S:139 Freed by task 18494: 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] kmem_cache_free+0x83/0x2a0 mm/slab.c:3743 net_free+0xca/0x110 net/core/net_namespace.c:385 net_drop_ns.part.11+0x26/0x30 net/core/net_namespace.c:392 net_drop_ns net/core/net_namespace.c:391 [inline] cleanup_net+0x977/0xcb0 net/core/net_namespace.c:535 process_one_work+0xc47/0x1bb0 kernel/workqueue.c:2113 worker_thread+0x223/0x1990 kernel/workqueue.c:2247 kthread+0x33c/0x400 kernel/kthread.c:238 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:406 The buggy address belongs to the object at ffff8801b1cca180 which belongs to the cache net_namespace of size 6720 The buggy address is located 4 bytes inside of 6720-byte region [ffff8801b1cca180, ffff8801b1ccbbc0) The buggy address belongs to the page: page:ffffea0006c73280 count:1 mapcount:0 mapping:ffff8801b1cca180 index:0x0 compound_mapcount: 0 audit: type=1400 audit(1520709440.849:11371): avc: denied { map } for pid=24985 comm="syz-executor5" path="/root/syz-executor5" dev="sda1" ino=16480 scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=unconfined_u:object_r:user_home_t:s0 tclass=file permissive=1 flags: 0x2fffc0000008100(slab|head) raw: 02fffc0000008100 ffff8801b1cca180 0000000000000000 0000000100000001 raw: ffffea0006c88220 ffffea00074648a0 ffff8801d9bece00 0000000000000000 page dumped because: kasan: bad access detected audit: type=1400 audit(1520709440.849:11372): avc: denied { map } for pid=24985 comm="syz-executor5" path="/sys/kernel/debug/kcov" dev="debugfs" ino=77 scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=system_u:object_r:debugfs_t:s0 tclass=file permissive=1 Memory state around the buggy address: ffff8801b1cca080: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff8801b1cca100: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff8801b1cca180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff8801b1cca200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8801b1cca280: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ================================================================== audit: type=1400 audit(1520709440.849:11373): avc: denied { sys_admin } for pid=24985 comm="syz-executor5" capability=21 scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tclass=cap_userns permissive=1