================================================================== 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 202 at addr ffff8801d6129e3c by task syz-executor2/6778 CPU: 0 PID: 6778 Comm: syz-executor2 Not tainted 4.15.0-rc4-next-20171221+ #78 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: 0033:0x452ac9 RSP: 002b:00007f2f422dbc58 EFLAGS: 00000212 ORIG_RAX: 00000000000000fa RAX: ffffffffffffffda RBX: 00007f2f422dc700 RCX: 0000000000452ac9 RDX: 00000000205cd000 RSI: 0000000020c86000 RDI: 0000000000000017 RBP: 0000000000000000 R08: 000000002010c000 R09: 0000000000000000 R10: 0000000000000001 R11: 0000000000000212 R12: 0000000000000000 R13: 0000000000a2f7ef R14: 00007f2f422dc9c0 R15: 0000000000000000 Allocated by task 6778: 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:3709 [inline] __kmalloc+0x162/0x760 mm/slab.c:3718 kmalloc include/linux/slab.h:521 [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 4429: 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:3489 [inline] kfree+0xd6/0x260 mm/slab.c:3804 skb_free_head+0x74/0xb0 net/core/skbuff.c:550 skb_release_data+0x58c/0x790 net/core/skbuff.c:570 skb_release_all+0x4a/0x60 net/core/skbuff.c:627 __kfree_skb net/core/skbuff.c:641 [inline] consume_skb+0x153/0x490 net/core/skbuff.c:701 netlink_broadcast_filtered+0x5d0/0x1360 net/netlink/af_netlink.c:1510 netlink_broadcast net/netlink/af_netlink.c:1532 [inline] nlmsg_multicast include/net/netlink.h:591 [inline] nlmsg_notify+0x91/0x150 net/netlink/af_netlink.c:2484 rtnl_notify+0xbb/0xe0 net/core/rtnetlink.c:713 __neigh_notify+0x118/0x140 net/core/neighbour.c:2901 neigh_cleanup_and_release+0x79/0xc0 net/core/neighbour.c:103 neigh_flush_dev+0x590/0x840 net/core/neighbour.c:277 neigh_ifdown+0x48/0x250 net/core/neighbour.c:293 addrconf_ifdown+0x143/0x14d0 net/ipv6/addrconf.c:3590 addrconf_notify+0x98e/0x21c0 net/ipv6/addrconf.c:3514 notifier_call_chain+0x136/0x2c0 kernel/notifier.c:93 __raw_notifier_call_chain kernel/notifier.c:394 [inline] raw_notifier_call_chain+0x2d/0x40 kernel/notifier.c:401 call_netdevice_notifiers_info+0x32/0x60 net/core/dev.c:1696 call_netdevice_notifiers net/core/dev.c:1714 [inline] dev_close_many+0x3fb/0x850 net/core/dev.c:1492 rollback_registered_many+0x4d5/0xdf0 net/core/dev.c:7283 rollback_registered+0x1be/0x3c0 net/core/dev.c:7348 unregister_netdevice_queue+0x2e3/0x5d0 net/core/dev.c:8341 unregister_netdevice include/linux/netdevice.h:2464 [inline] __tun_detach+0x1177/0x1550 drivers/net/tun.c:688 tun_detach drivers/net/tun.c:699 [inline] tun_chr_close+0x44/0x60 drivers/net/tun.c:2955 __fput+0x327/0x7e0 fs/file_table.c:209 ____fput+0x15/0x20 fs/file_table.c:243 task_work_run+0x199/0x270 kernel/task_work.c:113 exit_task_work include/linux/task_work.h:22 [inline] do_exit+0x9bb/0x1ad0 kernel/exit.c:869 do_group_exit+0x149/0x400 kernel/exit.c:972 get_signal+0x73f/0x16c0 kernel/signal.c:2337 do_signal+0x94/0x1ee0 arch/x86/kernel/signal.c:809 exit_to_usermode_loop+0x258/0x2f0 arch/x86/entry/common.c:161 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 ffff8801d6129d40 which belongs to the cache kmalloc-512 of size 512 The buggy address is located 252 bytes inside of 512-byte region [ffff8801d6129d40, ffff8801d6129f40) The buggy address belongs to the page: page:000000005bcd311b count:1 mapcount:0 mapping:000000008cf791a7 index:0x0 flags: 0x2fffc0000000100(slab) raw: 02fffc0000000100 ffff8801d61290c0 0000000000000000 0000000100000006 raw: ffffea0007580360 ffffea00075151e0 ffff8801dac00940 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff8801d6129d80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff8801d6129e00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 >ffff8801d6129e80: 00 00 00 00 00 00 00 00 00 fc fc fc fc fc fc fc ^ ffff8801d6129f00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff8801d6129f80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ==================================================================