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BUG: KMSAN: uninit-value in copy_siginfo_to_user+0x9cd/0x12c0 kernel/signal.c:2870
CPU: 1 PID: 13948 Comm: syz-executor6 Not tainted 4.17.0+ #22
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:990
 __msan_warning_32+0x70/0xc0 mm/kmsan/kmsan_instr.c:640
 copy_siginfo_to_user+0x9cd/0x12c0 kernel/signal.c:2870
 ptrace_peek_siginfo kernel/ptrace.c:741 [inline]
 ptrace_request+0x2032/0x2430 kernel/ptrace.c:912
 arch_ptrace+0xbcc/0x12c0 arch/x86/kernel/ptrace.c:877
 __do_sys_ptrace kernel/ptrace.c:1145 [inline]
 __se_sys_ptrace+0x309/0x850 kernel/ptrace.c:1110
 __x64_sys_ptrace+0x11e/0x170 kernel/ptrace.c:1110
 do_syscall_64+0x15b/0x230 arch/x86/entry/common.c:287
 entry_SYSCALL_64_after_hwframe+0x63/0xe7
RIP: 0033:0x455ba9
RSP: 002b:00007f2297acac68 EFLAGS: 00000246 ORIG_RAX: 0000000000000065
RAX: ffffffffffffffda RBX: 00007f2297acb6d4 RCX: 0000000000455ba9
RDX: 0000000020000004 RSI: 0000000000000001 RDI: 0000000000004209
RBP: 000000000072bea0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000020000100 R11: 0000000000000246 R12: 00000000ffffffff
R13: 00000000004c0a69 R14: 00000000004d0800 R15: 0000000000000000

Local variable description: ----kiov@ptrace_request
Variable was created at:
 ptrace_request+0x197/0x2430 kernel/ptrace.c:885
 arch_ptrace+0xbcc/0x12c0 arch/x86/kernel/ptrace.c:877
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