audit: type=1400 audit(1514656959.329:7): avc: denied { map } for pid=3194 comm="syzkaller150350" path="/root/syzkaller150350154" dev="sda1" ino=16481 scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=unconfined_u:object_r:user_home_t:s0 tclass=file permissive=1 ================================================================== BUG: KASAN: slab-out-of-bounds in cap_convert_nscap+0x501/0x610 security/commoncap.c:498 Read of size 4 at addr ffff8801c61c7280 by task syzkaller150350/3194 CPU: 0 PID: 3194 Comm: syzkaller150350 Not tainted 4.15.0-rc5+ #242 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_load4_noabort+0x14/0x20 mm/kasan/report.c:429 cap_convert_nscap+0x501/0x610 security/commoncap.c:498 setxattr+0x365/0x400 fs/xattr.c:446 SYSC_fsetxattr fs/xattr.c:508 [inline] SyS_fsetxattr+0x130/0x190 fs/xattr.c:497 entry_SYSCALL_64_fastpath+0x1f/0x96 RIP: 0033:0x43fcf9 RSP: 002b:00007ffdc0d4c408 EFLAGS: 00000203 ORIG_RAX: 00000000000000be RAX: ffffffffffffffda RBX: 6f72746e6f632f2e RCX: 000000000043fcf9 RDX: 00000000208c4fe9 RSI: 0000000020f4c000 RDI: 0000000000000003 RBP: 00000000006ca018 R08: 0000000000000001 R09: 0000000000000000 R10: 0000000000000001 R11: 0000000000000203 R12: 0000000000401660 R13: 00000000004016f0 R14: 0000000000000000 R15: 0000000000000000 Allocated by task 3194: 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_node mm/slab.c:3672 [inline] __kmalloc_node+0x47/0x70 mm/slab.c:3679 kmalloc_node include/linux/slab.h:541 [inline] kvmalloc_node+0x99/0xd0 mm/util.c:397 kvmalloc include/linux/mm.h:541 [inline] setxattr+0x152/0x400 fs/xattr.c:435 SYSC_fsetxattr fs/xattr.c:508 [inline] SyS_fsetxattr+0x130/0x190 fs/xattr.c:497 entry_SYSCALL_64_fastpath+0x1f/0x96 Freed by task 1679: 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:3488 [inline] kfree+0xd6/0x260 mm/slab.c:3803 kfree_link+0x15/0x20 fs/libfs.c:1066 do_delayed_call include/linux/delayed_call.h:28 [inline] put_link fs/namei.c:898 [inline] step_into fs/namei.c:1746 [inline] walk_component+0x54d/0x13d0 fs/namei.c:1803 link_path_walk+0x6a9/0x1470 fs/namei.c:2110 path_openat+0x2bc/0x3530 fs/namei.c:3519 do_filp_open+0x25b/0x3b0 fs/namei.c:3554 do_sys_open+0x502/0x6d0 fs/open.c:1059 SYSC_open fs/open.c:1077 [inline] SyS_open+0x2d/0x40 fs/open.c:1072 entry_SYSCALL_64_fastpath+0x1f/0x96 The buggy address belongs to the object at ffff8801c61c7280 which belongs to the cache kmalloc-32 of size 32 The buggy address is located 0 bytes inside of 32-byte region [ffff8801c61c7280, ffff8801c61c72a0) The buggy address belongs to the page: page:0000000077f4e811 count:1 mapcount:0 mapping:000000007008f3c4 index:0xffff8801c61c7fc1 flags: 0x2fffc0000000100(slab) raw: 02fffc0000000100 ffff8801c61c7000 ffff8801c61c7fc1 000000010000003f raw: ffffea000718a160 ffffea00071875a0 ffff8801dac001c0 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff8801c61c7180: fb fb fb fb fc fc fc fc fb fb fb fb fc fc fc fc ffff8801c61c7200: fb fb fb fb fc fc fc fc 00 00 00 fc fc fc fc fc >ffff8801c61c7280: 01 fc fc fc fc fc fc fc fb fb fb fb fc fc fc fc ^ ffff8801c61c7300: fb fb fb fb fc fc fc fc fb fb fb fb fc fc fc fc ffff8801c61c7380: fb fb fb fb fc fc fc fc 00 00 01 fc fc fc fc fc ==================================================================