================================================================== BUG: KASAN: slab-out-of-bounds in strnlen+0xc1/0xd0 lib/string.c:498 Read of size 1 at addr ffff8801d187aad1 by task syz-executor7/3342 CPU: 1 PID: 3342 Comm: syz-executor7 Not tainted 4.4.113-g202e079 #1 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 0000000000000000 928aafbd43341b50 ffff8801d30c7580 ffffffff81d0278d ffffea0007461e80 ffff8801d187aad1 0000000000000000 ffff8801d187aad1 ffff8801d30c7850 ffff8801d30c75b8 ffffffff814fd053 ffff8801d187aad1 Call Trace: [] __dump_stack lib/dump_stack.c:15 [inline] [] dump_stack+0xc1/0x124 lib/dump_stack.c:51 [] print_address_description+0x73/0x260 mm/kasan/report.c:252 [] kasan_report_error mm/kasan/report.c:351 [inline] [] kasan_report+0x285/0x370 mm/kasan/report.c:408 [] __asan_report_load1_noabort+0x14/0x20 mm/kasan/report.c:426 [] strnlen+0xc1/0xd0 lib/string.c:498 [] string.isra.4+0x4c/0x240 lib/vsprintf.c:518 [] vsnprintf+0x766/0x15f0 lib/vsprintf.c:1907 [] __request_module+0x14f/0x810 kernel/kmod.c:146 [] xt_request_find_target+0x8b/0xb0 net/netfilter/x_tables.c:255 [] check_compat_entry_size_and_hooks net/ipv4/netfilter/ip_tables.c:1490 [inline] [] translate_compat_table+0x568/0x1760 net/ipv4/netfilter/ip_tables.c:1582 [] ? 0xffffffff810002b8 [] compat_do_replace.isra.15+0x1f1/0x410 net/ipv4/netfilter/ip_tables.c:1690 [] compat_do_ipt_set_ctl+0x106/0x150 net/ipv4/netfilter/ip_tables.c:1721 [] compat_nf_sockopt net/netfilter/nf_sockopt.c:143 [inline] [] compat_nf_setsockopt+0x88/0x130 net/netfilter/nf_sockopt.c:155 [] compat_ip_setsockopt+0x9d/0xf0 net/ipv4/ip_sockglue.c:1255 [] inet_csk_compat_setsockopt+0x95/0x120 net/ipv4/inet_connection_sock.c:914 [] compat_tcp_setsockopt+0x3d/0x70 net/ipv4/tcp.c:2643 [] compat_sock_common_setsockopt+0xb2/0x140 net/core/sock.c:2670 [] C_SYSC_setsockopt net/compat.c:384 [inline] [] compat_SyS_setsockopt+0x149/0x290 net/compat.c:367 [] do_syscall_32_irqs_on arch/x86/entry/common.c:390 [inline] [] do_fast_syscall_32+0x314/0x890 arch/x86/entry/common.c:457 [] sysenter_flags_fixed+0xd/0x17 Allocated by task 3342: [] save_stack_trace+0x26/0x50 arch/x86/kernel/stacktrace.c:63 [] save_stack+0x43/0xd0 mm/kasan/kasan.c:512 [] set_track mm/kasan/kasan.c:524 [inline] [] kasan_kmalloc+0xad/0xe0 mm/kasan/kasan.c:616 [] __kmalloc+0x124/0x320 mm/slub.c:3613 [] kmalloc include/linux/slab.h:481 [inline] [] xt_alloc_table_info+0x71/0x100 net/netfilter/x_tables.c:911 [] compat_do_replace.isra.15+0x16b/0x410 net/ipv4/netfilter/ip_tables.c:1679 [] compat_do_ipt_set_ctl+0x106/0x150 net/ipv4/netfilter/ip_tables.c:1721 [] compat_nf_sockopt net/netfilter/nf_sockopt.c:143 [inline] [] compat_nf_setsockopt+0x88/0x130 net/netfilter/nf_sockopt.c:155 [] compat_ip_setsockopt+0x9d/0xf0 net/ipv4/ip_sockglue.c:1255 [] inet_csk_compat_setsockopt+0x95/0x120 net/ipv4/inet_connection_sock.c:914 [] compat_tcp_setsockopt+0x3d/0x70 net/ipv4/tcp.c:2643 [] compat_sock_common_setsockopt+0xb2/0x140 net/core/sock.c:2670 [] C_SYSC_setsockopt net/compat.c:384 [inline] [] compat_SyS_setsockopt+0x149/0x290 net/compat.c:367 [] do_syscall_32_irqs_on arch/x86/entry/common.c:390 [inline] [] do_fast_syscall_32+0x314/0x890 arch/x86/entry/common.c:457 [] sysenter_flags_fixed+0xd/0x17 Freed by task 0: (stack is not available) The buggy address belongs to the object at ffff8801d187aa00 which belongs to the cache kmalloc-256 of size 256 The buggy address is located 209 bytes inside of 256-byte region [ffff8801d187aa00, ffff8801d187ab00) The buggy address belongs to the page: ------------[ cut here ]------------ WARNING: CPU: 0 PID: 0 at lib/debugobjects.c:263 debug_print_object+0x17d/0x220 lib/debugobjects.c:260() ODEBUG: deactivate not available (active state 0) object type: timer_list hint: process_timeout+0x0/0x20 include/trace/events/timer.h:32