audit: type=1400 audit(1516862763.622:125): avc: denied { setgid } for pid=11240 comm="syz-executor6" capability=6 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 QAT: Invalid ioctl QAT: Invalid ioctl ================================================================== BUG: KASAN: use-after-free in __list_add_valid+0xb1/0xd0 lib/list_debug.c:23 Read of size 8 at addr ffff8801a48a5510 by task syz-executor0/11264 CPU: 1 PID: 11264 Comm: syz-executor0 Not tainted 4.15.0-rc9+ #188 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+0x194/0x257 lib/dump_stack.c:53 print_address_description+0x73/0x250 mm/kasan/report.c:252 kasan_report_error mm/kasan/report.c:351 [inline] kasan_report+0x25b/0x340 mm/kasan/report.c:409 __asan_report_load8_noabort+0x14/0x20 mm/kasan/report.c:430 __list_add_valid+0xb1/0xd0 lib/list_debug.c:23 __list_add include/linux/list.h:60 [inline] list_add include/linux/list.h:79 [inline] __add_wait_queue include/linux/wait.h:156 [inline] add_wait_queue+0xcf/0x290 kernel/sched/wait.c:30 vhost_poll_func+0x3d/0x50 drivers/vhost/vhost.c:165 poll_wait include/linux/poll.h:46 [inline] eventfd_poll+0xe8/0x1f0 fs/eventfd.c:123 vhost_poll_start+0x97/0x1c0 drivers/vhost/vhost.c:212 vhost_vring_ioctl+0xe28/0x19b0 drivers/vhost/vhost.c:1556 vhost_net_ioctl+0x9df/0x1910 drivers/vhost/net.c:1320 vhost_net_compat_ioctl+0x24/0x30 drivers/vhost/net.c:1332 C_SYSC_ioctl fs/compat_ioctl.c:1473 [inline] compat_SyS_ioctl+0x151/0x2a30 fs/compat_ioctl.c:1419 do_syscall_32_irqs_on arch/x86/entry/common.c:327 [inline] do_fast_syscall_32+0x3ee/0xf9d arch/x86/entry/common.c:389 entry_SYSENTER_compat+0x54/0x63 arch/x86/entry/entry_64_compat.S:129 RIP: 0023:0xf7f6fc79 RSP: 002b:00000000f774a08c EFLAGS: 00000296 ORIG_RAX: 0000000000000036 RAX: ffffffffffffffda RBX: 0000000000000017 RCX: 000000004008af20 RDX: 00000000208ffff8 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 Allocated by task 11253: 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:551 __do_kmalloc_node mm/slab.c:3672 [inline] __kmalloc_node+0x47/0x70 mm/slab.c:3679 kmalloc_node include/linux/slab.h:541 [inline] kvmalloc_node+0x64/0xd0 mm/util.c:397 kvmalloc include/linux/mm.h:541 [inline] vhost_net_open+0x27/0x670 drivers/vhost/net.c:902 misc_open+0x382/0x500 drivers/char/misc.c:154 chrdev_open+0x257/0x730 fs/char_dev.c:417 do_dentry_open+0x667/0xd40 fs/open.c:752 vfs_open+0x107/0x220 fs/open.c:866 do_last fs/namei.c:3379 [inline] path_openat+0x1151/0x3530 fs/namei.c:3519 do_filp_open+0x25b/0x3b0 fs/namei.c:3554 do_sys_open+0x502/0x6d0 fs/open.c:1059 C_SYSC_openat fs/open.c:1105 [inline] compat_SyS_openat+0x2d/0x40 fs/open.c:1103 do_syscall_32_irqs_on arch/x86/entry/common.c:327 [inline] do_fast_syscall_32+0x3ee/0xf9d arch/x86/entry/common.c:389 entry_SYSENTER_compat+0x54/0x63 arch/x86/entry/entry_64_compat.S:129 Freed by task 11253: save_stack+0x43/0xd0 mm/kasan/kasan.c:447 set_track mm/kasan/kasan.c:459 [inline] kasan_slab_free+0x71/0xc0 mm/kasan/kasan.c:524 __cache_free mm/slab.c:3488 [inline] kfree+0xd6/0x260 mm/slab.c:3803 kvfree+0x36/0x60 mm/util.c:416 vhost_net_release+0x159/0x190 drivers/vhost/net.c:1012 __fput+0x327/0x7e0 fs/file_table.c:210 ____fput+0x15/0x20 fs/file_table.c:244 task_work_run+0x199/0x270 kernel/task_work.c:113 tracehook_notify_resume include/linux/tracehook.h:191 [inline] exit_to_usermode_loop+0x296/0x310 arch/x86/entry/common.c:162 prepare_exit_to_usermode arch/x86/entry/common.c:195 [inline] syscall_return_slowpath arch/x86/entry/common.c:264 [inline] do_syscall_32_irqs_on arch/x86/entry/common.c:333 [inline] do_fast_syscall_32+0xbfd/0xf9d arch/x86/entry/common.c:389 entry_SYSENTER_compat+0x54/0x63 arch/x86/entry/entry_64_compat.S:129 The buggy address belongs to the object at ffff8801a48a5280 which belongs to the cache kmalloc-65536 of size 65536 The buggy address is located 656 bytes inside of 65536-byte region [ffff8801a48a5280, ffff8801a48b5280) The buggy address belongs to the page: page:ffffea0006922800 count:1 mapcount:0 mapping:ffff8801a48a5280 index:0x0 compound_mapcount: 0 flags: 0x2fffc0000008100(slab|head) raw: 02fffc0000008100 ffff8801a48a5280 0000000000000000 0000000100000001 raw: ffffea0006927820 ffffea0006927020 ffff8801dac02500 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff8801a48a5400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8801a48a5480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff8801a48a5500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff8801a48a5580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8801a48a5600: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================