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BUG: KMSAN: uninit-value in do_msgrcv+0x7dd/0x2220 ipc/msg.c:1056
CPU: 1 PID: 7459 Comm: syz-executor7 Not tainted 4.18.0-rc8+ #35
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+0x17c/0x1c0 lib/dump_stack.c:113
 kmsan_report+0x188/0x2a0 mm/kmsan/kmsan.c:956
 __msan_warning+0x70/0xc0 mm/kmsan/kmsan_instr.c:645
 do_msgrcv+0x7dd/0x2220 ipc/msg.c:1056
 ksys_msgrcv ipc/msg.c:1192 [inline]
 __do_sys_msgrcv ipc/msg.c:1198 [inline]
 __se_sys_msgrcv ipc/msg.c:1195 [inline]
 __x64_sys_msgrcv+0x160/0x1b0 ipc/msg.c:1195
 do_syscall_64+0x15b/0x220 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x63/0xe7
RIP: 0033:0x457089
Code: fd b4 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 cb b4 fb ff c3 66 2e 0f 1f 84 00 00 00 00 
RSP: 002b:00007f24df6aac78 EFLAGS: 00000246 ORIG_RAX: 0000000000000046
RAX: ffffffffffffffda RBX: 00007f24df6ab6d4 RCX: 0000000000457089
RDX: 0000000000000000 RSI: 0000000020000180 RDI: 0000000000000000
RBP: 0000000000930140 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff
R13: 00000000004d2aa8 R14: 00000000004c7da3 R15: 0000000000000001

Uninit was created at:
 kmsan_save_stack_with_flags mm/kmsan/kmsan.c:256 [inline]
 kmsan_internal_poison_shadow+0xb8/0x1b0 mm/kmsan/kmsan.c:181
 kmsan_kmalloc+0x98/0x100 mm/kmsan/kmsan_hooks.c:91
 __kmalloc_node+0x7bf/0x1220 mm/slub.c:3829
 kmalloc_node include/linux/slab.h:555 [inline]
 kvmalloc_node+0x19d/0x370 mm/util.c:423
 kvmalloc include/linux/mm.h:576 [inline]
 newque+0xb4/0x770 ipc/msg.c:139
 ipcget_new ipc/util.c:315 [inline]
 ipcget+0x2a7/0xd70 ipc/util.c:653
 ksys_msgget ipc/msg.c:289 [inline]
 __do_sys_msgget ipc/msg.c:294 [inline]
 __se_sys_msgget ipc/msg.c:292 [inline]
 __x64_sys_msgget+0x148/0x1d0 ipc/msg.c:292
 do_syscall_64+0x15b/0x220 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x63/0xe7
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