===================================================== BUG: KMSAN: kernel-infoleak in kmsan_copy_to_user+0x9c/0xb0 mm/kmsan/kmsan_hooks.c:249 CPU: 1 PID: 28643 Comm: syz-executor.5 Not tainted 5.12.0-rc6-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:79 [inline] dump_stack+0x24c/0x2e0 lib/dump_stack.c:120 kmsan_report+0xfb/0x1e0 mm/kmsan/kmsan_report.c:121 kmsan_internal_check_memory+0x1f5/0x500 mm/kmsan/kmsan.c:399 kmsan_copy_to_user+0x9c/0xb0 mm/kmsan/kmsan_hooks.c:249 instrument_copy_to_user include/linux/instrumented.h:121 [inline] copyout lib/iov_iter.c:145 [inline] _copy_to_iter+0x72d/0x2bc0 lib/iov_iter.c:624 copy_to_iter include/linux/uio.h:137 [inline] simple_copy_to_iter+0xf6/0x150 net/core/datagram.c:519 __skb_datagram_iter+0x2cb/0x1210 net/core/datagram.c:425 skb_copy_datagram_iter+0xd8/0x200 net/core/datagram.c:533 skb_copy_datagram_msg include/linux/skbuff.h:3599 [inline] netlink_recvmsg+0x772/0x1bc0 net/netlink/af_netlink.c:1985 ____sys_recvmsg+0x57f/0xd50 net/socket.c:888 ___sys_recvmsg net/socket.c:2611 [inline] __sys_recvmsg+0x585/0xce0 net/socket.c:2641 __do_sys_recvmsg net/socket.c:2651 [inline] __se_sys_recvmsg+0x97/0xb0 net/socket.c:2648 __x64_sys_recvmsg+0x4a/0x70 net/socket.c:2648 do_syscall_64+0x9f/0x140 arch/x86/entry/common.c:48 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x4665d9 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 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 73 01 c3 48 c7 c1 bc ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f8ff7462188 EFLAGS: 00000246 ORIG_RAX: 000000000000002f RAX: ffffffffffffffda RBX: 000000000056bf80 RCX: 00000000004665d9 RDX: 0000000000000000 RSI: 0000000020002640 RDI: 0000000000000003 RBP: 00000000004bfcb9 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000056bf80 R13: 0000000000a9fb1f R14: 00007f8ff7462300 R15: 0000000000022000 Uninit was created at: kmsan_save_stack_with_flags mm/kmsan/kmsan.c:120 [inline] kmsan_internal_poison_shadow+0x66/0xd0 mm/kmsan/kmsan.c:103 kmsan_slab_alloc+0x8e/0xe0 mm/kmsan/kmsan_hooks.c:76 slab_alloc_node mm/slub.c:2922 [inline] __kmalloc_node_track_caller+0xa4f/0x1470 mm/slub.c:4609 kmalloc_reserve net/core/skbuff.c:353 [inline] __alloc_skb+0x4dd/0xe90 net/core/skbuff.c:424 alloc_skb include/linux/skbuff.h:1103 [inline] netlink_dump+0x3ed/0x1650 net/netlink/af_netlink.c:2256 __netlink_dump_start+0xcfa/0xea0 net/netlink/af_netlink.c:2381 netlink_dump_start include/linux/netlink.h:262 [inline] inet_diag_handler_cmd+0x3f2/0x440 net/ipv4/inet_diag.c:1338 sock_diag_rcv_msg+0x245/0x610 net/core/sock_diag.c:257 netlink_rcv_skb+0x6fa/0x810 net/netlink/af_netlink.c:2502 sock_diag_rcv+0x63/0x80 net/core/sock_diag.c:276 netlink_unicast_kernel net/netlink/af_netlink.c:1312 [inline] netlink_unicast+0x11d6/0x14a0 net/netlink/af_netlink.c:1338 netlink_sendmsg+0x1740/0x1840 net/netlink/af_netlink.c:1927 sock_sendmsg_nosec net/socket.c:654 [inline] sock_sendmsg net/socket.c:674 [inline] ____sys_sendmsg+0xcfc/0x12f0 net/socket.c:2350 ___sys_sendmsg net/socket.c:2404 [inline] __sys_sendmsg+0x714/0x830 net/socket.c:2433 __do_sys_sendmsg net/socket.c:2442 [inline] __se_sys_sendmsg+0x97/0xb0 net/socket.c:2440 __x64_sys_sendmsg+0x4a/0x70 net/socket.c:2440 do_syscall_64+0x9f/0x140 arch/x86/entry/common.c:48 entry_SYSCALL_64_after_hwframe+0x44/0xae Bytes 68-71 of 628 are uninitialized Memory access of size 628 starts at ffff88808bc05000 Data copied to user address 0000000020000400 =====================================================