================================================================== BUG: KASAN: slab-out-of-bounds in strcmp+0x96/0xb0 lib/string.c:328 Read of size 1 at addr ffff8801c7cd5b83 by task syz-executor7/17621 CPU: 1 PID: 17621 Comm: syz-executor7 Not tainted 4.15.0-rc1+ #205 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:17 [inline] dump_stack+0x194/0x257 lib/dump_stack.c:53 print_address_description+0x73/0x250 mm/kasan/report.c:252 kasan_report_error mm/kasan/report.c:351 [inline] kasan_report+0x25b/0x340 mm/kasan/report.c:409 __asan_report_load1_noabort+0x14/0x20 mm/kasan/report.c:427 strcmp+0x96/0xb0 lib/string.c:328 security_context_to_sid_core+0x437/0x620 security/selinux/ss/services.c:1420 security_context_to_sid+0x32/0x40 security/selinux/ss/services.c:1479 selinux_setprocattr+0x51c/0xb50 security/selinux/hooks.c:5985 security_setprocattr+0x85/0xc0 security/security.c:1264 proc_pid_attr_write+0x1e6/0x280 fs/proc/base.c:2545 __vfs_write+0xef/0x970 fs/read_write.c:480 __kernel_write+0xfe/0x350 fs/read_write.c:501 write_pipe_buf+0x175/0x220 fs/splice.c:797 splice_from_pipe_feed fs/splice.c:502 [inline] __splice_from_pipe+0x328/0x730 fs/splice.c:626 splice_from_pipe+0x1e9/0x330 fs/splice.c:661 default_file_splice_write+0x40/0x90 fs/splice.c:809 do_splice_from fs/splice.c:851 [inline] direct_splice_actor+0x125/0x180 fs/splice.c:1018 splice_direct_to_actor+0x2c1/0x820 fs/splice.c:973 do_splice_direct+0x2a7/0x3d0 fs/splice.c:1061 do_sendfile+0x5d5/0xe90 fs/read_write.c:1413 SYSC_sendfile64 fs/read_write.c:1468 [inline] SyS_sendfile64+0xbd/0x160 fs/read_write.c:1460 do_syscall_64+0x26c/0x920 arch/x86/entry/common.c:285 entry_SYSCALL64_slow_path+0x25/0x25 RIP: 0033:0x4529d9 RSP: 002b:00007fbd38ac9c58 EFLAGS: 00000212 ORIG_RAX: 0000000000000028 RAX: ffffffffffffffda RBX: 0000000000758020 RCX: 00000000004529d9 RDX: 0000000020c18000 RSI: 0000000000000013 RDI: 0000000000000013 RBP: 000000000000044a R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000003 R11: 0000000000000212 R12: 00000000006f3790 R13: 00000000ffffffff R14: 00007fbd38aca6d4 R15: 0000000000000000 Allocated by task 17621: save_stack+0x43/0xd0 mm/kasan/kasan.c:447 set_track mm/kasan/kasan.c:459 [inline] kasan_kmalloc+0xad/0xe0 mm/kasan/kasan.c:551 __do_kmalloc mm/slab.c:3711 [inline] __kmalloc_track_caller+0x15e/0x760 mm/slab.c:3726 memdup_user+0x2c/0x90 mm/util.c:164 proc_pid_attr_write+0x115/0x280 fs/proc/base.c:2534 __vfs_write+0xef/0x970 fs/read_write.c:480 __kernel_write+0xfe/0x350 fs/read_write.c:501 write_pipe_buf+0x175/0x220 fs/splice.c:797 splice_from_pipe_feed fs/splice.c:502 [inline] __splice_from_pipe+0x328/0x730 fs/splice.c:626 splice_from_pipe+0x1e9/0x330 fs/splice.c:661 default_file_splice_write+0x40/0x90 fs/splice.c:809 do_splice_from fs/splice.c:851 [inline] direct_splice_actor+0x125/0x180 fs/splice.c:1018 splice_direct_to_actor+0x2c1/0x820 fs/splice.c:973 do_splice_direct+0x2a7/0x3d0 fs/splice.c:1061 do_sendfile+0x5d5/0xe90 fs/read_write.c:1413 SYSC_sendfile64 fs/read_write.c:1468 [inline] SyS_sendfile64+0xbd/0x160 fs/read_write.c:1460 do_syscall_64+0x26c/0x920 arch/x86/entry/common.c:285 return_from_SYSCALL_64+0x0/0x75 Freed by task 16017: save_stack+0x43/0xd0 mm/kasan/kasan.c:447 set_track mm/kasan/kasan.c:459 [inline] kasan_slab_free+0x71/0xc0 mm/kasan/kasan.c:524 __cache_free mm/slab.c:3491 [inline] kfree+0xca/0x250 mm/slab.c:3806 selinux_sk_free_security+0x4f/0x60 security/selinux/hooks.c:4908 security_sk_free+0x48/0x80 security/security.c:1431 sk_prot_free net/core/sock.c:1502 [inline] __sk_destruct+0x609/0x910 net/core/sock.c:1585 sk_destruct+0x47/0x80 net/core/sock.c:1593 __sk_free+0x57/0x230 net/core/sock.c:1601 sk_free+0x2a/0x40 net/core/sock.c:1612 sock_put include/net/sock.h:1655 [inline] sctp_close+0x487/0x980 net/sctp/socket.c:1590 inet_release+0xed/0x1c0 net/ipv4/af_inet.c:426 inet6_release+0x50/0x70 net/ipv6/af_inet6.c:433 sock_release+0x8d/0x1e0 net/socket.c:596 SYSC_socketpair net/socket.c:1446 [inline] SyS_socketpair+0x4ae/0x640 net/socket.c:1352 entry_SYSCALL_64_fastpath+0x1f/0x96 The buggy address belongs to the object at ffff8801c7cd5b80 which belongs to the cache kmalloc-32 of size 32 The buggy address is located 3 bytes inside of 32-byte region [ffff8801c7cd5b80, ffff8801c7cd5ba0) The buggy address belongs to the page: page:000000009848884e count:1 mapcount:0 mapping:000000008721cf8c index:0xffff8801c7cd5fc1 flags: 0x2fffc0000000100(slab) raw: 02fffc0000000100 ffff8801c7cd5000 ffff8801c7cd5fc1 000000010000003e raw: ffffea00071d2520 ffffea00072ca660 ffff8801db0001c0 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff8801c7cd5a80: fb fb fb fb fc fc fc fc fb fb fb fb fc fc fc fc ffff8801c7cd5b00: fb fb fb fb fc fc fc fc fb fb fb fb fc fc fc fc >ffff8801c7cd5b80: 03 fc fc fc fc fc fc fc fb fb fb fb fc fc fc fc ^ ffff8801c7cd5c00: fb fb fb fb fc fc fc fc fb fb fb fb fc fc fc fc ffff8801c7cd5c80: 00 fc fc fc fc fc fc fc fb fb fb fb fc fc fc fc ==================================================================