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BUG: KMSAN: uninit-value in __list_add_valid+0x2a4/0x450 lib/list_debug.c:26
CPU: 0 PID: 18355 Comm: syz-executor2 Not tainted 4.17.0+ #9
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+0x185/0x1d0 lib/dump_stack.c:113
 kmsan_report+0x188/0x2a0 mm/kmsan/kmsan.c:1125
 __msan_warning_32+0x70/0xc0 mm/kmsan/kmsan_instr.c:620
 __list_add_valid+0x2a4/0x450 lib/list_debug.c:26
 __list_add include/linux/list.h:60 [inline]
 list_add_tail include/linux/list.h:93 [inline]
 cma_listen_on_all drivers/infiniband/core/cma.c:2301 [inline]
 rdma_listen+0x65f/0x10f0 drivers/infiniband/core/cma.c:3327
 ucma_listen+0x4e9/0x630 drivers/infiniband/core/ucma.c:1096
 ucma_write+0x57e/0x5f0 drivers/infiniband/core/ucma.c:1676
 __vfs_write+0x1aa/0x9f0 fs/read_write.c:485
 vfs_write+0x467/0x8c0 fs/read_write.c:549
 ksys_write fs/read_write.c:598 [inline]
 __do_sys_write fs/read_write.c:610 [inline]
 __se_sys_write fs/read_write.c:607 [inline]
 __x64_sys_write+0x1bf/0x3e0 fs/read_write.c:607
 do_syscall_64+0x15b/0x230 arch/x86/entry/common.c:287
 entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x455b29
RSP: 002b:00007fddc22dbc68 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007fddc22dc6d4 RCX: 0000000000455b29
RDX: 0000000000000010 RSI: 0000000020000000 RDI: 0000000000000014
RBP: 000000000072bea0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff
R13: 00000000004c25fd R14: 00000000004d3c30 R15: 0000000000000000

Uninit was created at:
 kmsan_save_stack_with_flags mm/kmsan/kmsan.c:282 [inline]
 kmsan_internal_poison_shadow+0xb8/0x1b0 mm/kmsan/kmsan.c:192
 kmsan_kmalloc+0x94/0x100 mm/kmsan/kmsan.c:318
 kmsan_slab_alloc+0x10/0x20 mm/kmsan/kmsan.c:325
 slab_post_alloc_hook mm/slab.h:446 [inline]
 slab_alloc_node mm/slub.c:2753 [inline]
 __kmalloc_node_track_caller+0xb35/0x11b0 mm/slub.c:4395
 __kmalloc_reserve net/core/skbuff.c:138 [inline]
 __alloc_skb+0x2cb/0x9e0 net/core/skbuff.c:206
 alloc_skb include/linux/skbuff.h:988 [inline]
 alloc_skb_with_frags+0x1e6/0xb80 net/core/skbuff.c:5254
 sock_alloc_send_pskb+0xb56/0x11a0 net/core/sock.c:2088
 sock_alloc_send_skb+0xca/0xe0 net/core/sock.c:2105
 __ip_append_data+0x29a0/0x4020 net/ipv4/ip_output.c:970
 ip_make_skb+0x81f/0xe90 net/ipv4/ip_output.c:1492
 udp_sendmsg+0x2c4d/0x33c0 net/ipv4/udp.c:1035
 udpv6_sendmsg+0x1291/0x3f40 net/ipv6/udp.c:1175
 inet_sendmsg+0x3fc/0x760 net/ipv4/af_inet.c:798
 sock_sendmsg_nosec net/socket.c:629 [inline]
 sock_sendmsg net/socket.c:639 [inline]
 ___sys_sendmsg+0xec8/0x1320 net/socket.c:2117
 __sys_sendmsg net/socket.c:2155 [inline]
 __do_sys_sendmsg net/socket.c:2164 [inline]
 __se_sys_sendmsg net/socket.c:2162 [inline]
 __x64_sys_sendmsg+0x331/0x460 net/socket.c:2162
 do_syscall_64+0x15b/0x230 arch/x86/entry/common.c:287
 entry_SYSCALL_64_after_hwframe+0x44/0xa9
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