================================================================== BUG: KASAN: slab-out-of-bounds in string+0x1e8/0x200 lib/vsprintf.c:595 audit: type=1400 audit(1517022639.570:90): avc: denied { dyntransition } for pid=19540 comm="syz-executor0" scontext=unconfined_u:system_r:insmod_t:s0-s0:c0 tcontext=unconfined_u:system_r:insmod_t:s0-s0:c0 tclass=process permissive=1 Read of size 1 at addr ffff8801d0716e90 by task syz-executor1/19577 CPU: 0 PID: 19577 Comm: syz-executor1 Not tainted 4.15.0-rc9+ #192 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 audit: type=1400 audit(1517022639.570:91): avc: denied { map } for pid=19587 comm="syz-executor0" path="/dev/usbmon0" dev="devtmpfs" ino=190 scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=system_u:object_r:usbmon_device_t:s0 tclass=chr_file permissive=1 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_load1_noabort+0x14/0x20 mm/kasan/report.c:427 string+0x1e8/0x200 lib/vsprintf.c:595 vsnprintf+0x863/0x1900 lib/vsprintf.c:2282 __request_module+0x1bf/0xc20 kernel/kmod.c:143 xt_request_find_target+0x8b/0xb0 net/netfilter/x_tables.c:257 check_compat_entry_size_and_hooks net/ipv4/netfilter/ip_tables.c:1339 [inline] translate_compat_table+0x910/0x1b90 net/ipv4/netfilter/ip_tables.c:1426 compat_do_replace.isra.15+0x30e/0x720 net/ipv4/netfilter/ip_tables.c:1529 compat_do_ipt_set_ctl+0x106/0x150 net/ipv4/netfilter/ip_tables.c:1558 compat_nf_sockopt net/netfilter/nf_sockopt.c:144 [inline] compat_nf_setsockopt+0x88/0x130 net/netfilter/nf_sockopt.c:156 compat_ip_setsockopt+0x9d/0xf0 net/ipv4/ip_sockglue.c:1285 compat_raw_setsockopt+0xb7/0xd0 net/ipv4/raw.c:866 compat_sock_common_setsockopt+0xb2/0x140 net/core/sock.c:2979 C_SYSC_setsockopt net/compat.c:403 [inline] compat_SyS_setsockopt+0x17c/0x410 net/compat.c:386 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: 0023:0xf7f7ac79 RSP: 002b:00000000f777608c EFLAGS: 00000296 ORIG_RAX: 000000000000016e RAX: ffffffffffffffda RBX: 0000000000000013 RCX: 0000000000000000 RDX: 0000000000000040 RSI: 0000000020007000 RDI: 00000000000000ec RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 Allocated by task 19577: 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+0x99/0xd0 mm/util.c:397 kvmalloc include/linux/mm.h:541 [inline] xt_alloc_table_info+0x64/0xe0 net/netfilter/x_tables.c:1006 compat_do_replace.isra.15+0x17f/0x720 net/ipv4/netfilter/ip_tables.c:1518 compat_do_ipt_set_ctl+0x106/0x150 net/ipv4/netfilter/ip_tables.c:1558 compat_nf_sockopt net/netfilter/nf_sockopt.c:144 [inline] compat_nf_setsockopt+0x88/0x130 net/netfilter/nf_sockopt.c:156 compat_ip_setsockopt+0x9d/0xf0 net/ipv4/ip_sockglue.c:1285 compat_raw_setsockopt+0xb7/0xd0 net/ipv4/raw.c:866 compat_sock_common_setsockopt+0xb2/0x140 net/core/sock.c:2979 C_SYSC_setsockopt net/compat.c:403 [inline] compat_SyS_setsockopt+0x17c/0x410 net/compat.c:386 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 1816: 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 seq_release+0x59/0x70 fs/seq_file.c:366 kernfs_fop_release+0x10b/0x180 fs/kernfs/file.c:781 __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+0x490/0x550 arch/x86/entry/common.c:264 entry_SYSCALL_64_fastpath+0x9e/0xa0 The buggy address belongs to the object at ffff8801d0716dc0 which belongs to the cache kmalloc-256 of size 256 The buggy address is located 208 bytes inside of 256-byte region [ffff8801d0716dc0, ffff8801d0716ec0) The buggy address belongs to the page: page:ffffea000741c580 count:1 mapcount:0 mapping:ffff8801d0716000 index:0xffff8801d0716500 flags: 0x2fffc0000000100(slab) raw: 02fffc0000000100 ffff8801d0716000 ffff8801d0716500 0000000100000009 raw: ffffea00074238a0 ffffea00074094e0 ffff8801dac007c0 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff8801d0716d80: fc fc fc fc fc fc fc fc 00 00 00 00 00 00 00 00 ffff8801d0716e00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 >ffff8801d0716e80: 00 00 fc fc fc fc fc fc fc fc fc fc fc fc fc fc ^ ffff8801d0716f00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff8801d0716f80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ==================================================================