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BUG: KMSAN: uninit-value in __list_add_valid+0x292/0x430 lib/list_debug.c:26
CPU: 0 PID: 13949 Comm: syz-executor.2 Not tainted 5.0.0+ #16
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+0x173/0x1d0 lib/dump_stack.c:113
 kmsan_report+0x131/0x2a0 mm/kmsan/kmsan.c:636
 __msan_warning+0x7a/0xf0 mm/kmsan/kmsan_instr.c:310
 __list_add_valid+0x292/0x430 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:2477 [inline]
 rdma_listen+0x64a/0xfe0 drivers/infiniband/core/cma.c:3492
 ucma_listen+0x4fa/0x630 drivers/infiniband/core/ucma.c:1100
 ucma_write+0x5c7/0x640 drivers/infiniband/core/ucma.c:1689
 __vfs_write+0x1e2/0xc20 fs/read_write.c:485
 vfs_write+0x481/0x920 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+0x17a/0x370 fs/read_write.c:607
 __x64_sys_write+0x4a/0x70 fs/read_write.c:607
 do_syscall_64+0xbc/0xf0 arch/x86/entry/common.c:291
 entry_SYSCALL_64_after_hwframe+0x63/0xe7
RIP: 0033:0x458209
Code: ad b8 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 7b b8 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007f34c966cc78 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000458209
RDX: 0000000000000010 RSI: 0000000020000000 RDI: 0000000000000003
RBP: 000000000073bf00 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f34c966d6d4
R13: 00000000004c7440 R14: 00000000004dcf40 R15: 00000000ffffffff

Uninit was created at:
 kmsan_save_stack_with_flags mm/kmsan/kmsan.c:205 [inline]
 kmsan_internal_poison_shadow+0x92/0x150 mm/kmsan/kmsan.c:159
 kmsan_kmalloc+0xa6/0x130 mm/kmsan/kmsan_hooks.c:173
 kmsan_slab_alloc+0xe/0x10 mm/kmsan/kmsan_hooks.c:182
 slab_post_alloc_hook mm/slab.h:445 [inline]
 slab_alloc_node mm/slub.c:2773 [inline]
 __kmalloc_node_track_caller+0xe9e/0xff0 mm/slub.c:4398
 __kmalloc_reserve net/core/skbuff.c:140 [inline]
 __alloc_skb+0x309/0xa20 net/core/skbuff.c:208
 alloc_skb include/linux/skbuff.h:1012 [inline]
 __tcp_send_ack+0xfb/0x840 net/ipv4/tcp_output.c:3629
 tcp_send_ack+0x68/0x90 net/ipv4/tcp_output.c:3656
 tcp_cleanup_rbuf+0x764/0x7f0 net/ipv4/tcp.c:1585
 tcp_recvmsg+0x37e6/0x4630 net/ipv4/tcp.c:2163
 inet_recvmsg+0x4fb/0x600 net/ipv4/af_inet.c:830
 sock_recvmsg_nosec net/socket.c:795 [inline]
 sock_recvmsg net/socket.c:802 [inline]
 sock_read_iter+0x45b/0x4e0 net/socket.c:879
 call_read_iter include/linux/fs.h:1857 [inline]
 new_sync_read fs/read_write.c:406 [inline]
 __vfs_read+0x94e/0xbf0 fs/read_write.c:418
 vfs_read+0x359/0x6f0 fs/read_write.c:452
 ksys_read fs/read_write.c:578 [inline]
 __do_sys_read fs/read_write.c:588 [inline]
 __se_sys_read+0x17a/0x370 fs/read_write.c:586
 __x64_sys_read+0x4a/0x70 fs/read_write.c:586
 do_syscall_64+0xbc/0xf0 arch/x86/entry/common.c:291
 entry_SYSCALL_64_after_hwframe+0x63/0xe7
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