================================================================== BUG: KASAN: slab-out-of-bounds in fl6_update_dst+0x2bb/0x2c0 net/ipv6/exthdrs.c:1356 Read of size 16 at addr ffff8880937c1258 by task syz-executor184/7029 CPU: 0 PID: 7029 Comm: syz-executor184 Not tainted 5.7.0-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+0x188/0x20d lib/dump_stack.c:118 print_address_description.constprop.0.cold+0xd3/0x315 mm/kasan/report.c:382 __kasan_report.cold+0x35/0x4d mm/kasan/report.c:511 kasan_report+0x33/0x50 mm/kasan/common.c:625 fl6_update_dst+0x2bb/0x2c0 net/ipv6/exthdrs.c:1356 sctp_v6_get_dst+0x5e7/0x1c30 net/sctp/ipv6.c:276 sctp_transport_route+0x125/0x350 net/sctp/transport.c:297 sctp_assoc_add_peer+0x5a0/0x1030 net/sctp/associola.c:659 sctp_connect_new_asoc+0x19b/0x580 net/sctp/socket.c:1092 sctp_sendmsg_new_asoc net/sctp/socket.c:1694 [inline] sctp_sendmsg+0x1396/0x1f30 net/sctp/socket.c:2004 inet_sendmsg+0x99/0xe0 net/ipv4/af_inet.c:807 sock_sendmsg_nosec net/socket.c:652 [inline] sock_sendmsg+0xcf/0x120 net/socket.c:672 ____sys_sendmsg+0x308/0x7e0 net/socket.c:2362 ___sys_sendmsg+0x100/0x170 net/socket.c:2416 __sys_sendmmsg+0x195/0x480 net/socket.c:2506 __do_sys_sendmmsg net/socket.c:2535 [inline] __se_sys_sendmmsg net/socket.c:2532 [inline] __x64_sys_sendmmsg+0x99/0x100 net/socket.c:2532 do_syscall_64+0xf6/0x7d0 arch/x86/entry/common.c:295 entry_SYSCALL_64_after_hwframe+0x49/0xb3 RIP: 0033:0x440309 Code: 18 89 d0 c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 fb 13 fc ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007fffd69d01b8 EFLAGS: 00000246 ORIG_RAX: 0000000000000133 RAX: ffffffffffffffda RBX: 00000000004002c8 RCX: 0000000000440309 RDX: 0000000000000001 RSI: 0000000020000140 RDI: 0000000000000003 RBP: 00000000006ca018 R08: 00000000004002c8 R09: 00000000004002c8 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000401b90 R13: 0000000000401c20 R14: 0000000000000000 R15: 0000000000000000 Allocated by task 7029: save_stack+0x1b/0x40 mm/kasan/common.c:49 set_track mm/kasan/common.c:57 [inline] __kasan_kmalloc mm/kasan/common.c:495 [inline] __kasan_kmalloc.constprop.0+0xbf/0xd0 mm/kasan/common.c:468 __do_kmalloc mm/slab.c:3656 [inline] __kmalloc+0x161/0x7a0 mm/slab.c:3665 kmalloc include/linux/slab.h:560 [inline] sock_kmalloc net/core/sock.c:2166 [inline] sock_kmalloc+0xb5/0x100 net/core/sock.c:2157 ipv6_renew_options+0x274/0x940 net/ipv6/exthdrs.c:1275 do_ipv6_setsockopt.isra.0+0x2eaf/0x42f0 net/ipv6/ipv6_sockglue.c:435 ipv6_setsockopt+0xfb/0x180 net/ipv6/ipv6_sockglue.c:949 sctp_setsockopt+0x13e/0x7090 net/sctp/socket.c:4685 __sys_setsockopt+0x248/0x480 net/socket.c:2132 __do_sys_setsockopt net/socket.c:2148 [inline] __se_sys_setsockopt net/socket.c:2145 [inline] __x64_sys_setsockopt+0xba/0x150 net/socket.c:2145 do_syscall_64+0xf6/0x7d0 arch/x86/entry/common.c:295 entry_SYSCALL_64_after_hwframe+0x49/0xb3 Freed by task 5049: save_stack+0x1b/0x40 mm/kasan/common.c:49 set_track mm/kasan/common.c:57 [inline] kasan_set_free_info mm/kasan/common.c:317 [inline] __kasan_slab_free+0xf7/0x140 mm/kasan/common.c:456 __cache_free mm/slab.c:3426 [inline] kfree+0x109/0x2b0 mm/slab.c:3757 tomoyo_path_perm+0x236/0x400 security/tomoyo/file.c:842 security_inode_getattr+0xeb/0x150 security/security.c:1273 vfs_getattr+0x22/0x60 fs/stat.c:117 vfs_statx_fd+0x6a/0xb0 fs/stat.c:147 vfs_fstat include/linux/fs.h:3295 [inline] __do_sys_newfstat+0x8b/0x100 fs/stat.c:388 do_syscall_64+0xf6/0x7d0 arch/x86/entry/common.c:295 entry_SYSCALL_64_after_hwframe+0x49/0xb3 The buggy address belongs to the object at ffff8880937c1200 which belongs to the cache kmalloc-96 of size 96 The buggy address is located 88 bytes inside of 96-byte region [ffff8880937c1200, ffff8880937c1260) The buggy address belongs to the page: page:ffffea00024df040 refcount:1 mapcount:0 mapping:00000000d119b653 index:0xffff8880937c1400 flags: 0xfffe0000000200(slab) raw: 00fffe0000000200 ffffea00025ab248 ffffea00024b5388 ffff8880aa000540 raw: ffff8880937c1400 ffff8880937c1000 0000000100000019 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff8880937c1100: fb fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc ffff8880937c1180: 00 00 00 00 00 00 00 00 00 fc fc fc fc fc fc fc >ffff8880937c1200: 00 00 00 00 00 00 00 00 00 00 00 fc fc fc fc fc ^ ffff8880937c1280: fb fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc ffff8880937c1300: fb fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc ==================================================================