[syzbot] [kernel?] KMSAN: uninit-value in profile_hits (3)

From: syzbot
Date: Tue Dec 26 2023 - 10:59:28 EST


Hello,

syzbot found the following issue on:

HEAD commit: 1978a14f70af x86: kmsan: enable KMSAN builds for x86
git tree: https://github.com/google/kmsan.git master
console output: https://syzkaller.appspot.com/x/log.txt?x=13b7a95b700000
kernel config: https://syzkaller.appspot.com/x/.config?x=d830111cc3be873
dashboard link: https://syzkaller.appspot.com/bug?extid=b1a83ab2a9eb9321fbdd
compiler: clang version 14.0.0 (/usr/local/google/src/llvm-git-monorepo 2b554920f11c8b763cd9ed9003f4e19b919b8e1f), GNU ld (GNU Binutils for Debian) 2.35.2
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=14b5476b700000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=142c9237700000

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+b1a83ab2a9eb9321fbdd@xxxxxxxxxxxxxxxxxxxxxxxxx

=====================================================
BUG: KMSAN: uninit-value in do_profile_hits kernel/profile.c:236 [inline]
BUG: KMSAN: uninit-value in profile_hits+0xaf2/0x1260 kernel/profile.c:326
do_profile_hits kernel/profile.c:236 [inline]
profile_hits+0xaf2/0x1260 kernel/profile.c:326
profile_hit include/linux/profile.h:58 [inline]
profile_tick+0x241/0x250 kernel/profile.c:336
tick_sched_handle kernel/time/tick-sched.c:227 [inline]
tick_sched_timer+0x4bd/0x610 kernel/time/tick-sched.c:1428
__run_hrtimer+0x49f/0xc50 kernel/time/hrtimer.c:1685
__hrtimer_run_queues kernel/time/hrtimer.c:1749 [inline]
hrtimer_interrupt+0x7f7/0x2100 kernel/time/hrtimer.c:1811
local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1086 [inline]
__sysvec_apic_timer_interrupt+0x178/0x5e0 arch/x86/kernel/apic/apic.c:1103
sysvec_apic_timer_interrupt+0x9d/0xc0 arch/x86/kernel/apic/apic.c:1097
asm_sysvec_apic_timer_interrupt+0x12/0x20
__raw_spin_unlock_irq include/linux/spinlock_api_smp.h:160 [inline]
_raw_spin_unlock_irq+0x36/0x60 kernel/locking/spinlock.c:202
spin_unlock_irq include/linux/spinlock.h:399 [inline]
__set_current_blocked+0xb0c/0xb90 kernel/signal.c:3051
sigprocmask kernel/signal.c:3085 [inline]
__do_sys_rt_sigprocmask kernel/signal.c:3162 [inline]
__se_sys_rt_sigprocmask+0x438/0x5b0 kernel/signal.c:3145
__x64_sys_rt_sigprocmask+0x11e/0x170 kernel/signal.c:3145
do_syscall_x64 arch/x86/entry/common.c:51 [inline]
do_syscall_64+0x54/0xd0 arch/x86/entry/common.c:81
entry_SYSCALL_64_after_hwframe+0x44/0xae

Local variable iter.i created at:
new_sync_read fs/read_write.c:393 [inline]
vfs_read+0xb8a/0x1980 fs/read_write.c:481
ksys_read+0x28b/0x510 fs/read_write.c:619

CPU: 1 PID: 3474 Comm: sshd Not tainted 5.17.0-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
=====================================================


---
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