Hello, syzbot found the following issue on: HEAD commit: 4b6c093e Merge tag 'block-5.9-2020-08-14' of git://git.ker.. git tree: upstream console output: https://syzkaller.appspot.com/x/log.txt?x=14741412900000 kernel config: https://syzkaller.appspot.com/x/.config?x=a98b778f5fca0653 dashboard link: https://syzkaller.appspot.com/bug?extid=cfc0247ac173f597aaaa compiler: gcc (GCC) 10.1.0-syz 20200507 userspace arch: i386 syz repro: https://syzkaller.appspot.com/x/repro.syz?x=1283a731900000 C reproducer: https://syzkaller.appspot.com/x/repro.c?x=10dd10ce900000 IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+cfc0247ac173f597aaaa@xxxxxxxxxxxxxxxxxxxxxxxxx ================================================================== BUG: KASAN: slab-out-of-bounds in memset include/linux/string.h:391 [inline] BUG: KASAN: slab-out-of-bounds in xt_compat_target_from_user+0x232/0x470 net/netfilter/x_tables.c:1129 Write of size 4 at addr ffff88809c971ba1 by task syz-executor166/6841 CPU: 1 PID: 6841 Comm: syz-executor166 Not tainted 5.8.0-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+0x18f/0x20d lib/dump_stack.c:118 print_address_description.constprop.0.cold+0xae/0x497 mm/kasan/report.c:383 __kasan_report mm/kasan/report.c:513 [inline] kasan_report.cold+0x1f/0x37 mm/kasan/report.c:530 check_memory_region_inline mm/kasan/generic.c:186 [inline] check_memory_region+0x13d/0x180 mm/kasan/generic.c:192 memset+0x20/0x40 mm/kasan/common.c:84 memset include/linux/string.h:391 [inline] xt_compat_target_from_user+0x232/0x470 net/netfilter/x_tables.c:1129 compat_copy_entry_from_user net/ipv6/netfilter/ip6_tables.c:1392 [inline] translate_compat_table+0x1011/0x1720 net/ipv6/netfilter/ip6_tables.c:1455 compat_do_replace.constprop.0+0x1f0/0x470 net/ipv6/netfilter/ip6_tables.c:1526 do_ip6t_set_ctl+0x5b0/0xb73 net/ipv6/netfilter/ip6_tables.c:1633 nf_setsockopt+0x83/0xe0 net/netfilter/nf_sockopt.c:101 ipv6_setsockopt+0x122/0x180 net/ipv6/ipv6_sockglue.c:1008 udpv6_setsockopt+0x76/0xc0 net/ipv6/udp.c:1626 __sys_setsockopt+0x2db/0x610 net/socket.c:2132 __do_sys_setsockopt net/socket.c:2143 [inline] __se_sys_setsockopt net/socket.c:2140 [inline] __ia32_sys_setsockopt+0xb9/0x150 net/socket.c:2140 do_syscall_32_irqs_on arch/x86/entry/common.c:84 [inline] __do_fast_syscall_32+0x57/0x80 arch/x86/entry/common.c:126 do_fast_syscall_32+0x2f/0x70 arch/x86/entry/common.c:149 entry_SYSENTER_compat_after_hwframe+0x4d/0x5c RIP: 0023:0xf7fd3549 Code: b8 01 10 06 03 74 b4 01 10 07 03 74 b0 01 10 08 03 74 d8 01 00 00 00 00 00 00 00 00 00 00 00 00 00 51 52 55 89 e5 0f 34 cd 80 <5d> 5a 59 c3 90 90 90 90 eb 0d 90 90 90 90 90 90 90 90 90 90 90 90 RSP: 002b:00000000f7fad18c EFLAGS: 00000292 ORIG_RAX: 000000000000016e RAX: ffffffffffffffda RBX: 0000000000000004 RCX: 0000000000000029 RDX: 0000000000000040 RSI: 0000000020000a00 RDI: 0000000000000001 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 Allocated by task 6841: kasan_save_stack+0x1b/0x40 mm/kasan/common.c:48 kasan_set_track mm/kasan/common.c:56 [inline] __kasan_kmalloc.constprop.0+0xbf/0xd0 mm/kasan/common.c:461 kmalloc_node include/linux/slab.h:577 [inline] kvmalloc_node+0x61/0xf0 mm/util.c:574 kvmalloc include/linux/mm.h:750 [inline] xt_alloc_table_info+0x3c/0xa0 net/netfilter/x_tables.c:1176 translate_compat_table+0xc50/0x1720 net/ipv6/netfilter/ip6_tables.c:1442 compat_do_replace.constprop.0+0x1f0/0x470 net/ipv6/netfilter/ip6_tables.c:1526 do_ip6t_set_ctl+0x5b0/0xb73 net/ipv6/netfilter/ip6_tables.c:1633 nf_setsockopt+0x83/0xe0 net/netfilter/nf_sockopt.c:101 ipv6_setsockopt+0x122/0x180 net/ipv6/ipv6_sockglue.c:1008 udpv6_setsockopt+0x76/0xc0 net/ipv6/udp.c:1626 __sys_setsockopt+0x2db/0x610 net/socket.c:2132 __do_sys_setsockopt net/socket.c:2143 [inline] __se_sys_setsockopt net/socket.c:2140 [inline] __ia32_sys_setsockopt+0xb9/0x150 net/socket.c:2140 do_syscall_32_irqs_on arch/x86/entry/common.c:84 [inline] __do_fast_syscall_32+0x57/0x80 arch/x86/entry/common.c:126 do_fast_syscall_32+0x2f/0x70 arch/x86/entry/common.c:149 entry_SYSENTER_compat_after_hwframe+0x4d/0x5c The buggy address belongs to the object at ffff88809c971800 which belongs to the cache kmalloc-1k of size 1024 The buggy address is located 929 bytes inside of 1024-byte region [ffff88809c971800, ffff88809c971c00) The buggy address belongs to the page: page:00000000d9974640 refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff88809c971000 pfn:0x9c971 flags: 0xfffe0000000200(slab) raw: 00fffe0000000200 ffffea000269a448 ffffea00027cc908 ffff8880aa040700 raw: ffff88809c971000 ffff88809c971000 0000000100000001 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff88809c971a80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff88809c971b00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 >ffff88809c971b80: 00 00 fc fc fc fc fc fc fc fc fc fc fc fc fc fc ^ ffff88809c971c00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff88809c971c80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ================================================================== --- This report is generated by a bot. It may contain errors. See https://goo.gl/tpsmEJ for more information about syzbot. syzbot engineers can be reached at syzkaller@xxxxxxxxxxxxxxxx. syzbot will keep track of this issue. See: https://goo.gl/tpsmEJ#status for how to communicate with syzbot. syzbot can test patches for this issue, for details see: https://goo.gl/tpsmEJ#testing-patches
