================================================================== BUG: KASAN: slab-out-of-bounds in fl6_update_dst+0x159/0x1a0 net/ipv6/exthdrs.c:1356 Read of size 16 at addr ffff888097e87298 by task syz-executor.4/10309 CPU: 0 PID: 10309 Comm: syz-executor.4 Not tainted 5.7.0-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+0x1e9/0x30e lib/dump_stack.c:118 print_address_description+0x66/0x5a0 mm/kasan/report.c:383 __kasan_report mm/kasan/report.c:513 [inline] kasan_report+0x132/0x1d0 mm/kasan/report.c:530 check_memory_region_inline mm/kasan/generic.c:183 [inline] check_memory_region+0x2b5/0x2f0 mm/kasan/generic.c:192 memcpy+0x25/0x60 mm/kasan/common.c:105 fl6_update_dst+0x159/0x1a0 net/ipv6/exthdrs.c:1356 udpv6_sendmsg+0x1ce7/0x3200 net/ipv6/udp.c:1431 sock_sendmsg_nosec net/socket.c:652 [inline] sock_sendmsg net/socket.c:672 [inline] __sys_sendto+0x429/0x5c0 net/socket.c:1995 __do_sys_sendto net/socket.c:2007 [inline] __se_sys_sendto net/socket.c:2003 [inline] __x64_sys_sendto+0xda/0xf0 net/socket.c:2003 do_syscall_64+0xf3/0x1b0 arch/x86/entry/common.c:295 entry_SYSCALL_64_after_hwframe+0x49/0xb3 RIP: 0033:0x45ca59 Code: 0d b7 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 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 db b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007ffaa427cc78 EFLAGS: 00000246 ORIG_RAX: 000000000000002c RAX: ffffffffffffffda RBX: 0000000000501e60 RCX: 000000000045ca59 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000004 RBP: 000000000078bfa0 R08: 0000000020000300 R09: 000000000000001c R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff R13: 0000000000000a30 R14: 00000000004cd10c R15: 00007ffaa427d6d4 Allocated by task 10297: save_stack mm/kasan/common.c:48 [inline] set_track mm/kasan/common.c:56 [inline] __kasan_kmalloc+0x103/0x140 mm/kasan/common.c:494 __do_kmalloc mm/slab.c:3656 [inline] __kmalloc+0x24b/0x330 mm/slab.c:3665 kmalloc include/linux/slab.h:560 [inline] sock_kmalloc+0x98/0x100 net/core/sock.c:2255 ipv6_renew_options+0x27c/0xa70 net/ipv6/exthdrs.c:1275 do_ipv6_setsockopt+0x2467/0x3a30 net/ipv6/ipv6_sockglue.c:471 ipv6_setsockopt+0x49/0x160 net/ipv6/ipv6_sockglue.c:900 __sys_setsockopt+0x564/0x710 net/socket.c:2127 __do_sys_setsockopt net/socket.c:2143 [inline] __se_sys_setsockopt net/socket.c:2140 [inline] __x64_sys_setsockopt+0xb1/0xc0 net/socket.c:2140 do_syscall_64+0xf3/0x1b0 arch/x86/entry/common.c:295 entry_SYSCALL_64_after_hwframe+0x49/0xb3 Freed by task 10008: save_stack mm/kasan/common.c:48 [inline] set_track mm/kasan/common.c:56 [inline] kasan_set_free_info mm/kasan/common.c:316 [inline] __kasan_slab_free+0x114/0x170 mm/kasan/common.c:455 __cache_free mm/slab.c:3426 [inline] kfree+0x10a/0x220 mm/slab.c:3757 security_cred_free+0xbf/0x100 security/security.c:1604 put_cred_rcu+0xca/0x350 kernel/cred.c:114 do_faccessat+0x3cc/0x870 fs/open.c:464 do_syscall_64+0xf3/0x1b0 arch/x86/entry/common.c:295 entry_SYSCALL_64_after_hwframe+0x49/0xb3 The buggy address belongs to the object at ffff888097e87200 which belongs to the cache kmalloc-192 of size 192 The buggy address is located 152 bytes inside of 192-byte region [ffff888097e87200, ffff888097e872c0) The buggy address belongs to the page: page:ffffea00025fa1c0 refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff888097e87e00 flags: 0xfffe0000000200(slab) raw: 00fffe0000000200 ffffea0002a097c8 ffffea000228f588 ffff8880aa400000 raw: ffff888097e87e00 ffff888097e87000 0000000100000006 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff888097e87180: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc ffff888097e87200: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 >ffff888097e87280: 00 00 00 fc fc fc fc fc fc fc fc fc fc fc fc fc ^ ffff888097e87300: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff888097e87380: 00 00 fc fc fc fc fc fc fc fc fc fc fc fc fc fc ==================================================================