================================================================== BUG: KASAN: use-after-free in smc_diag_msg_common_fill net/smc/smc_diag.c:43 [inline] BUG: KASAN: use-after-free in __smc_diag_dump.isra.0+0x281e/0x2b80 net/smc/smc_diag.c:93 Read of size 8 at addr ffff88805e8c4020 by task syz-executor3/30096 CPU: 0 PID: 30096 Comm: syz-executor3 Not tainted 4.20.0+ #3 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x1db/0x2d0 lib/dump_stack.c:113 print_address_description.cold+0x7c/0x20d mm/kasan/report.c:256 kasan_report_error mm/kasan/report.c:354 [inline] kasan_report mm/kasan/report.c:412 [inline] kasan_report.cold+0x8c/0x2ba mm/kasan/report.c:396 __asan_report_load8_noabort+0x14/0x20 mm/kasan/report.c:433 smc_diag_msg_common_fill net/smc/smc_diag.c:43 [inline] __smc_diag_dump.isra.0+0x281e/0x2b80 net/smc/smc_diag.c:93 smc_diag_dump_proto.isra.0+0x2e7/0x3c0 net/smc/smc_diag.c:211 smc_diag_dump+0x27/0x80 net/smc/smc_diag.c:225 netlink_dump+0x5f2/0x1070 net/netlink/af_netlink.c:2244 __netlink_dump_start+0x5b4/0x7e0 net/netlink/af_netlink.c:2352 netlink_dump_start include/linux/netlink.h:225 [inline] smc_diag_handler_dump+0x2a7/0x350 net/smc/smc_diag.c:242 __sock_diag_cmd net/core/sock_diag.c:232 [inline] sock_diag_rcv_msg+0x322/0x410 net/core/sock_diag.c:263 netlink_rcv_skb+0x17d/0x410 net/netlink/af_netlink.c:2477 sock_diag_rcv+0x2b/0x40 net/core/sock_diag.c:274 netlink_unicast_kernel net/netlink/af_netlink.c:1310 [inline] netlink_unicast+0x574/0x770 net/netlink/af_netlink.c:1336 netlink_sendmsg+0xa05/0xf90 net/netlink/af_netlink.c:1917 sock_sendmsg_nosec net/socket.c:621 [inline] sock_sendmsg+0xdd/0x130 net/socket.c:631 ___sys_sendmsg+0x7ec/0x910 net/socket.c:2116 __sys_sendmsg+0x112/0x270 net/socket.c:2154 __do_sys_sendmsg net/socket.c:2163 [inline] __se_sys_sendmsg net/socket.c:2161 [inline] __x64_sys_sendmsg+0x78/0xb0 net/socket.c:2161 do_syscall_64+0x1a3/0x800 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x457ec9 Code: 6d b7 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 3b b7 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007f4861c47c78 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000457ec9 RDX: 0000000000000000 RSI: 0000000020000040 RDI: 0000000000000006 RBP: 000000000073bf00 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f4861c486d4 R13: 00000000004c52f9 R14: 00000000004d8d58 R15: 00000000ffffffff Allocated by task 30096: save_stack+0x45/0xd0 mm/kasan/kasan.c:448 set_track mm/kasan/kasan.c:460 [inline] kasan_kmalloc mm/kasan/kasan.c:553 [inline] kasan_kmalloc+0xce/0xf0 mm/kasan/kasan.c:531 kasan_slab_alloc+0xf/0x20 mm/kasan/kasan.c:490 kmem_cache_alloc+0x12e/0x700 mm/slab.c:3554 sock_alloc_inode+0x1d/0x260 net/socket.c:244 alloc_inode+0x66/0x190 fs/inode.c:210 new_inode_pseudo+0x71/0x1b0 fs/inode.c:906 sock_alloc+0x41/0x270 net/socket.c:547 __sock_create+0x173/0x930 net/socket.c:1241 sock_create_kern+0x3b/0x50 net/socket.c:1323 smc_create+0x17f/0x3c0 net/smc/af_smc.c:1921 __sock_create+0x532/0x930 net/socket.c:1277 sock_create net/socket.c:1317 [inline] __sys_socket+0x106/0x260 net/socket.c:1347 __do_sys_socket net/socket.c:1356 [inline] __se_sys_socket net/socket.c:1354 [inline] __x64_sys_socket+0x73/0xb0 net/socket.c:1354 do_syscall_64+0x1a3/0x800 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe Freed by task 30092: save_stack+0x45/0xd0 mm/kasan/kasan.c:448 set_track mm/kasan/kasan.c:460 [inline] __kasan_slab_free+0x102/0x150 mm/kasan/kasan.c:521 kasan_slab_free+0xe/0x10 mm/kasan/kasan.c:528 __cache_free mm/slab.c:3498 [inline] kmem_cache_free+0x86/0x260 mm/slab.c:3760 sock_destroy_inode+0x4f/0x60 net/socket.c:272 destroy_inode+0x14f/0x1f0 fs/inode.c:267 evict+0x5c3/0x940 fs/inode.c:575 iput_final fs/inode.c:1550 [inline] iput fs/inode.c:1576 [inline] iput+0x67e/0xae0 fs/inode.c:1562 __sock_release+0x1e6/0x250 net/socket.c:590 sock_release+0x18/0x20 net/socket.c:598 smc_release+0x29c/0x9c0 net/smc/af_smc.c:155 __sock_release+0xd3/0x250 net/socket.c:579 sock_close+0x1b/0x30 net/socket.c:1141 __fput+0x3c5/0xaf0 fs/file_table.c:278 ____fput+0x16/0x20 fs/file_table.c:309 task_work_run+0x1f4/0x2b0 kernel/task_work.c:113 tracehook_notify_resume include/linux/tracehook.h:188 [inline] exit_to_usermode_loop+0x32a/0x3b0 arch/x86/entry/common.c:166 prepare_exit_to_usermode arch/x86/entry/common.c:197 [inline] syscall_return_slowpath arch/x86/entry/common.c:268 [inline] do_syscall_64+0x696/0x800 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe The buggy address belongs to the object at ffff88805e8c4000 which belongs to the cache sock_inode_cache(65:syz3) of size 976 The buggy address is located 32 bytes inside of 976-byte region [ffff88805e8c4000, ffff88805e8c43d0) The buggy address belongs to the page: page:ffffea00017a3100 count:1 mapcount:0 mapping:ffff8880a806d600 index:0xffff88805e8c4ffd flags: 0x1fffc0000000200(slab) raw: 01fffc0000000200 ffffea00025cee08 ffffea000213ad48 ffff8880a806d600 raw: ffff88805e8c4ffd ffff88805e8c4000 0000000100000002 ffff888068d0e740 page dumped because: kasan: bad access detected page->mem_cgroup:ffff888068d0e740 Memory state around the buggy address: ffff88805e8c3f00: 00 00 00 00 00 00 00 00 00 00 00 00 fc fc fc fc ffff88805e8c3f80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff88805e8c4000: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88805e8c4080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88805e8c4100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================