audit: type=1400 audit(1513919078.260:7): avc: denied { map } for pid=3152 comm="syzkaller717822" path="/root/syzkaller717822551" 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 memcpy include/linux/string.h:344 [inline] BUG: KASAN: slab-out-of-bounds in sha3_update+0xdf/0x2e0 crypto/sha3_generic.c:161 Write of size 192 at addr ffff8801cf0e3b3c by task syzkaller717822/3152 CPU: 0 PID: 3152 Comm: syzkaller717822 Not tainted 4.15.0-rc4+ #232 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 check_memory_region_inline mm/kasan/kasan.c:260 [inline] check_memory_region+0x137/0x190 mm/kasan/kasan.c:267 memcpy+0x37/0x50 mm/kasan/kasan.c:303 memcpy include/linux/string.h:344 [inline] sha3_update+0xdf/0x2e0 crypto/sha3_generic.c:161 crypto_shash_update+0xda/0x240 crypto/shash.c:110 hmac_update+0x7e/0xa0 crypto/hmac.c:122 crypto_shash_update+0xda/0x240 crypto/shash.c:110 kdf_ctr security/keys/dh.c:181 [inline] keyctl_dh_compute_kdf security/keys/dh.c:226 [inline] __keyctl_dh_compute+0x160f/0x1990 security/keys/dh.c:398 keyctl_dh_compute+0xac/0xf3 security/keys/dh.c:434 SYSC_keyctl security/keys/keyctl.c:1741 [inline] SyS_keyctl+0x72/0x2c0 security/keys/keyctl.c:1637 entry_SYSCALL_64_fastpath+0x1f/0x96 RIP: 0033:0x43feb9 RSP: 002b:00007ffd3aef51a8 EFLAGS: 00000217 ORIG_RAX: 00000000000000fa RAX: ffffffffffffffda RBX: 00000000004002c8 RCX: 000000000043feb9 RDX: 0000000020c2cfff RSI: 00000000204c8ff4 RDI: 0000000000000017 RBP: 00000000006ca018 R08: 00000000208e6fd4 R09: 0000000000000000 R10: 0000000000000001 R11: 0000000000000217 R12: 0000000000401820 R13: 00000000004018b0 R14: 0000000000000000 R15: 0000000000000000 Allocated by task 3152: 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+0x162/0x760 mm/slab.c:3717 kmalloc include/linux/slab.h:504 [inline] kdf_alloc security/keys/dh.c:111 [inline] __keyctl_dh_compute+0x2b0/0x1990 security/keys/dh.c:288 keyctl_dh_compute+0xac/0xf3 security/keys/dh.c:434 SYSC_keyctl security/keys/keyctl.c:1741 [inline] SyS_keyctl+0x72/0x2c0 security/keys/keyctl.c:1637 entry_SYSCALL_64_fastpath+0x1f/0x96 Freed by task 1637: 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 kernfs_fop_release+0x13f/0x180 fs/kernfs/file.c:783 __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+0x94/0x96 The buggy address belongs to the object at ffff8801cf0e3a40 which belongs to the cache kmalloc-512 of size 512 The buggy address is located 252 bytes inside of 512-byte region [ffff8801cf0e3a40, ffff8801cf0e3c40) The buggy address belongs to the page: page:000000001ae65fa7 count:1 mapcount:0 mapping:0000000077bf18b4 index:0xffff8801cf0e3cc0 flags: 0x2fffc0000000100(slab) raw: 02fffc0000000100 ffff8801cf0e3040 ffff8801cf0e3cc0 0000000100000005 raw: ffff8801db001738 ffffea00073c1c20 ffff8801db000940 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff8801cf0e3a80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff8801cf0e3b00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 >ffff8801cf0e3b80: 00 00 00 00 00 00 00 00 00 fc fc fc fc fc fc fc ^ ffff8801cf0e3c00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff8801cf0e3c80: fc fc fc fc fc fc fc fc fb fb fb fb fb fb fb fb ==================================================================