Hello, syzbot found the following issue on: HEAD commit: 4f1b4da5 Merge branch 'net-atlantic-various-features' git tree: net-next console output: https://syzkaller.appspot.com/x/log.txt?x=14b3a040900000 kernel config: https://syzkaller.appspot.com/x/.config?x=2b7b67c0c1819c87 dashboard link: https://syzkaller.appspot.com/bug?extid=0e4699d000d8b874d8dc compiler: gcc (GCC) 10.1.0-syz 20200507 syz repro: https://syzkaller.appspot.com/x/repro.syz?x=14c93358900000 C reproducer: https://syzkaller.appspot.com/x/repro.c?x=14ab61f0900000 IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+0e4699d000d8b874d8dc@xxxxxxxxxxxxxxxxxxxxxxxxx sctp: [Deprecated]: syz-executor496 (pid 6834) Use of struct sctp_assoc_value in delayed_ack socket option. Use struct sctp_sack_info instead ================================================================== BUG: KASAN: slab-out-of-bounds in sctp_setsockopt_delayed_ack net/sctp/socket.c:2771 [inline] BUG: KASAN: slab-out-of-bounds in sctp_setsockopt net/sctp/socket.c:4499 [inline] BUG: KASAN: slab-out-of-bounds in sctp_setsockopt+0x9488/0x95e0 net/sctp/socket.c:4431 Write of size 4 at addr ffff8880a2709288 by task syz-executor496/6834 CPU: 0 PID: 6834 Comm: syz-executor496 Not tainted 5.8.0-rc4-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/0x436 mm/kasan/report.c:383 __kasan_report mm/kasan/report.c:513 [inline] kasan_report.cold+0x1f/0x37 mm/kasan/report.c:530 sctp_setsockopt_delayed_ack net/sctp/socket.c:2771 [inline] sctp_setsockopt net/sctp/socket.c:4499 [inline] sctp_setsockopt+0x9488/0x95e0 net/sctp/socket.c:4431 __sys_setsockopt+0x337/0x6a0 net/socket.c:2137 __do_sys_setsockopt net/socket.c:2153 [inline] __se_sys_setsockopt net/socket.c:2150 [inline] __x64_sys_setsockopt+0xba/0x150 net/socket.c:2150 do_syscall_64+0x60/0xe0 arch/x86/entry/common.c:384 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x440229 Code: Bad RIP value. RSP: 002b:00007ffc07ceda28 EFLAGS: 00000246 ORIG_RAX: 0000000000000036 RAX: ffffffffffffffda RBX: 00000000004002c8 RCX: 0000000000440229 RDX: 0000000000000010 RSI: 0000000000000084 RDI: 0000000000000003 RBP: 00000000006ca018 R08: 0000000000000008 R09: 00000000004002c8 R10: 0000000020000100 R11: 0000000000000246 R12: 0000000000401a30 R13: 0000000000401ac0 R14: 0000000000000000 R15: 0000000000000000 Allocated by task 6834: save_stack+0x1b/0x40 mm/kasan/common.c:48 set_track mm/kasan/common.c:56 [inline] __kasan_kmalloc.constprop.0+0xc2/0xd0 mm/kasan/common.c:494 __do_kmalloc mm/slab.c:3656 [inline] __kmalloc_track_caller+0x178/0x330 mm/slab.c:3671 memdup_user+0x22/0xd0 mm/util.c:172 sctp_setsockopt net/sctp/socket.c:4452 [inline] sctp_setsockopt+0x17a/0x95e0 net/sctp/socket.c:4431 __sys_setsockopt+0x337/0x6a0 net/socket.c:2137 __do_sys_setsockopt net/socket.c:2153 [inline] __se_sys_setsockopt net/socket.c:2150 [inline] __x64_sys_setsockopt+0xba/0x150 net/socket.c:2150 do_syscall_64+0x60/0xe0 arch/x86/entry/common.c:384 entry_SYSCALL_64_after_hwframe+0x44/0xa9 Freed by task 4827: save_stack+0x1b/0x40 mm/kasan/common.c:48 set_track mm/kasan/common.c:56 [inline] kasan_set_free_info mm/kasan/common.c:316 [inline] __kasan_slab_free+0xf5/0x140 mm/kasan/common.c:455 __cache_free mm/slab.c:3426 [inline] kfree+0x103/0x2c0 mm/slab.c:3757 tomoyo_path2_perm+0x28a/0x600 security/tomoyo/file.c:947 tomoyo_path_rename+0xd2/0x130 security/tomoyo/tomoyo.c:279 security_path_rename+0x1b5/0x2e0 security/security.c:1135 do_renameat2+0x481/0xbf0 fs/namei.c:4446 __do_sys_rename fs/namei.c:4496 [inline] __se_sys_rename fs/namei.c:4494 [inline] __x64_sys_rename+0x5d/0x80 fs/namei.c:4494 do_syscall_64+0x60/0xe0 arch/x86/entry/common.c:384 entry_SYSCALL_64_after_hwframe+0x44/0xa9 The buggy address belongs to the object at ffff8880a2709280 which belongs to the cache kmalloc-32 of size 32 The buggy address is located 8 bytes inside of 32-byte region [ffff8880a2709280, ffff8880a27092a0) The buggy address belongs to the page: page:ffffea000289c240 refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff8880a2709fc1 flags: 0xfffe0000000200(slab) raw: 00fffe0000000200 ffffea00026c1108 ffffea00026ae848 ffff8880aa0001c0 raw: ffff8880a2709fc1 ffff8880a2709000 000000010000003f 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff8880a2709180: 06 fc fc fc fc fc fc fc 06 fc fc fc fc fc fc fc ffff8880a2709200: 06 fc fc fc fc fc fc fc fb fb fb fb fc fc fc fc >ffff8880a2709280: 00 fc fc fc fc fc fc fc 05 fc fc fc fc fc fc fc ^ ffff8880a2709300: fb fb fb fb fc fc fc fc 06 fc fc fc fc fc fc fc ffff8880a2709380: 06 fc fc fc fc fc fc fc 06 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
