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BUG: KMSAN: uninit-value in pointer+0x11e5/0x1410 lib/vsprintf.c:1852
CPU: 1 PID: 4481 Comm: syz-executor420 Not tainted 4.16.0+ #87
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:17 [inline]
 dump_stack+0x185/0x1d0 lib/dump_stack.c:53
 kmsan_report+0x142/0x240 mm/kmsan/kmsan.c:1067
 __msan_warning_32+0x6c/0xb0 mm/kmsan/kmsan_instr.c:683
 pointer+0x11e5/0x1410 lib/vsprintf.c:1852
 vsnprintf+0xa2d/0x33c0 lib/vsprintf.c:2286
 seq_vprintf fs/seq_file.c:400 [inline]
 seq_printf+0x29f/0x420 fs/seq_file.c:415
 proc_pid_stack+0x326/0x470 fs/proc/base.c:449
 proc_single_show+0x1af/0x300 fs/proc/base.c:747
 seq_read+0xc7d/0x2260 fs/seq_file.c:237
 do_loop_readv_writev fs/read_write.c:673 [inline]
 do_iter_read+0x880/0xd70 fs/read_write.c:897
 vfs_readv fs/read_write.c:959 [inline]
 do_preadv+0x3a1/0x580 fs/read_write.c:1043
 SYSC_preadv+0xc6/0xe0 fs/read_write.c:1093
 SyS_preadv+0x77/0xa0 fs/read_write.c:1088
 do_syscall_64+0x309/0x430 arch/x86/entry/common.c:287
 entry_SYSCALL_64_after_hwframe+0x3d/0xa2
RIP: 0033:0x445599
RSP: 002b:00007f07753c0d18 EFLAGS: 00000246 ORIG_RAX: 0000000000000127
RAX: ffffffffffffffda RBX: 00000000006dac24 RCX: 0000000000445599
RDX: 0000000000000002 RSI: 0000000020000200 RDI: 0000000000000003
RBP: 0000000000000000 R08: 65732f636f72702f R09: 65732f636f72702f
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f07753c0d20
R13: 00000000006dac20 R14: 0000000000000000 R15: 0000000000000002

Uninit was stored to memory at:
 kmsan_save_stack_with_flags mm/kmsan/kmsan.c:278 [inline]
 kmsan_save_stack mm/kmsan/kmsan.c:293 [inline]
 kmsan_internal_chain_origin+0x12b/0x210 mm/kmsan/kmsan.c:684
 __msan_chain_origin+0x69/0xc0 mm/kmsan/kmsan_instr.c:528
 save_stack_address arch/x86/kernel/stacktrace.c:29 [inline]
 __save_stack_trace+0x829/0xb00 arch/x86/kernel/stacktrace.c:50
 save_stack_trace_tsk+0x258/0x2f0 arch/x86/kernel/stacktrace.c:82
 proc_pid_stack+0x26a/0x470 fs/proc/base.c:446
 proc_single_show+0x1af/0x300 fs/proc/base.c:747
 seq_read+0xc7d/0x2260 fs/seq_file.c:237
 do_loop_readv_writev fs/read_write.c:673 [inline]
 do_iter_read+0x880/0xd70 fs/read_write.c:897
 vfs_readv fs/read_write.c:959 [inline]
 do_preadv+0x3a1/0x580 fs/read_write.c:1043
 SYSC_preadv+0xc6/0xe0 fs/read_write.c:1093
 SyS_preadv+0x77/0xa0 fs/read_write.c:1088
 do_syscall_64+0x309/0x430 arch/x86/entry/common.c:287
 entry_SYSCALL_64_after_hwframe+0x3d/0xa2
Uninit was stored to memory at:
 kmsan_save_stack_with_flags mm/kmsan/kmsan.c:278 [inline]
 kmsan_save_stack mm/kmsan/kmsan.c:293 [inline]
 kmsan_internal_chain_origin+0x12b/0x210 mm/kmsan/kmsan.c:684
 __msan_chain_origin+0x69/0xc0 mm/kmsan/kmsan_instr.c:528
 update_stack_state+0x959/0xa40 arch/x86/kernel/unwind_frame.c:257
 unwind_next_frame+0x618/0xe50 arch/x86/kernel/unwind_frame.c:329
 __save_stack_trace+0x734/0xb00 arch/x86/kernel/stacktrace.c:48
 save_stack_trace_tsk+0x258/0x2f0 arch/x86/kernel/stacktrace.c:82
 proc_pid_stack+0x26a/0x470 fs/proc/base.c:446
 proc_single_show+0x1af/0x300 fs/proc/base.c:747
 seq_read+0xc7d/0x2260 fs/seq_file.c:237
 do_loop_readv_writev fs/read_write.c:673 [inline]
 do_iter_read+0x880/0xd70 fs/read_write.c:897
 vfs_readv fs/read_write.c:959 [inline]
 do_preadv+0x3a1/0x580 fs/read_write.c:1043
 SYSC_preadv+0xc6/0xe0 fs/read_write.c:1093
 SyS_preadv+0x77/0xa0 fs/read_write.c:1088
 do_syscall_64+0x309/0x430 arch/x86/entry/common.c:287
 entry_SYSCALL_64_after_hwframe+0x3d/0xa2
Local variable description: ----flags.i.i.i@rcu_all_qs
Variable was created at:
 rcu_all_qs+0x32/0x1f0 kernel/rcu/tree.c:478
 _cond_resched+0x3c/0xd0 kernel/sched/core.c:4935
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