audit: type=1400 audit(1514753657.623:7): avc: denied { map } for pid=3504 comm="syzkaller926656" path="/root/syzkaller926656864" 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_inode_getsecurity+0x621/0x7d0 security/commoncap.c:408 Read of size 4 at addr ffff8801bea30b00 by task syzkaller926656/3504 CPU: 1 PID: 3504 Comm: syzkaller926656 Not tainted 4.15.0-rc5+ #244 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_inode_getsecurity+0x621/0x7d0 security/commoncap.c:408 security_inode_getsecurity+0xcd/0x110 security/security.c:809 xattr_getsecurity+0xd3/0x1f0 fs/xattr.c:244 vfs_getxattr+0xc8/0x110 fs/xattr.c:333 getxattr+0x116/0x2a0 fs/xattr.c:540 path_getxattr+0xed/0x170 fs/xattr.c:568 SYSC_getxattr fs/xattr.c:580 [inline] SyS_getxattr+0x33/0x40 fs/xattr.c:577 entry_SYSCALL_64_fastpath+0x23/0x9a RIP: 0033:0x43fd09 RSP: 002b:00007ffcf95c1178 EFLAGS: 00000217 ORIG_RAX: 00000000000000bf RAX: ffffffffffffffda RBX: 0030656c69662f2e RCX: 000000000043fd09 RDX: 0000000020227f74 RSI: 0000000020b29f57 RDI: 000000002072d000 RBP: 00000000006ca018 R08: 0000000000000000 R09: 0000000000000000 R10: 000000000000008c R11: 0000000000000217 R12: 0000000000401670 R13: 0000000000401700 R14: 0000000000000000 R15: 0000000000000000 Allocated by task 3504: 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:3708 [inline] __kmalloc_track_caller+0x15e/0x760 mm/slab.c:3723 __do_krealloc mm/slab_common.c:1407 [inline] krealloc+0x65/0xc0 mm/slab_common.c:1454 vfs_getxattr_alloc+0x177/0x270 fs/xattr.c:290 cap_inode_getsecurity+0xfa/0x7d0 security/commoncap.c:399 security_inode_getsecurity+0xcd/0x110 security/security.c:809 xattr_getsecurity+0xd3/0x1f0 fs/xattr.c:244 vfs_getxattr+0xc8/0x110 fs/xattr.c:333 getxattr+0x116/0x2a0 fs/xattr.c:540 path_getxattr+0xed/0x170 fs/xattr.c:568 SYSC_getxattr fs/xattr.c:580 [inline] SyS_getxattr+0x33/0x40 fs/xattr.c:577 entry_SYSCALL_64_fastpath+0x23/0x9a Freed by task 1970: 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 single_release+0x88/0xb0 fs/seq_file.c:603 __fput+0x327/0x7e0 fs/file_table.c:210 ____fput+0x15/0x20 fs/file_table.c:244 task_work_run+0x199/0x270 kernel/task_work.c:113 tracehook_notify_resume include/linux/tracehook.h:191 [inline] exit_to_usermode_loop+0x296/0x310 arch/x86/entry/common.c:162 prepare_exit_to_usermode arch/x86/entry/common.c:195 [inline] syscall_return_slowpath+0x490/0x550 arch/x86/entry/common.c:264 entry_SYSCALL_64_fastpath+0x98/0x9a The buggy address belongs to the object at ffff8801bea30b00 which belongs to the cache kmalloc-32 of size 32 The buggy address is located 0 bytes inside of 32-byte region [ffff8801bea30b00, ffff8801bea30b20) The buggy address belongs to the page: page:00000000bdc64004 count:1 mapcount:0 mapping:00000000f92bbf6b index:0xffff8801bea30fc1 flags: 0x2fffc0000000100(slab) raw: 02fffc0000000100 ffff8801bea30000 ffff8801bea30fc1 000000010000003f raw: ffffea0006fa4ea0 ffffea0006fa54e0 ffff8801dac001c0 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff8801bea30a00: fb fb fb fb fc fc fc fc 00 00 00 fc fc fc fc fc ffff8801bea30a80: fb fb fb fb fc fc fc fc fb fb fb fb fc fc fc fc >ffff8801bea30b00: 01 fc fc fc fc fc fc fc fb fb fb fb fc fc fc fc ^ ffff8801bea30b80: fb fb fb fb fc fc fc fc fb fb fb fb fc fc fc fc ffff8801bea30c00: fb fb fb fb fc fc fc fc fb fb fb fb fc fc fc fc ==================================================================