[syzbot] [kernel?] KMSAN: uninit-value in timerqueue_del

[syzbot <syzbot+d5e61dcfda08821a226d@syzkaller.appspotmail.com>]

Hello,

syzbot found the following issue on:

HEAD commit:    1e1ba8d23dae Merge tag 'timers-clocksource-2025-03-26' of ..
git tree:       upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=1357abb0580000
kernel config:  https://syzkaller.appspot.com/x/.config?x=887673359f1a92bf
dashboard link: https://syzkaller.appspot.com/bug?extid=d5e61dcfda08821a226d
compiler:       Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
userspace arch: i386

Unfortunately, I don't have any reproducer for this issue yet.

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/721f329c0fc6/disk-1e1ba8d2.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/4bc26a0ed6a7/vmlinux-1e1ba8d2.xz
kernel image: https://storage.googleapis.com/syzbot-assets/09d5f4dc3101/bzImage-1e1ba8d2.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+d5e61dcfda08821a226d@syzkaller.appspotmail.com

ffff88813fc04fc0: ffff88813115aac8 (0xffff88813115aac8)
ffff88813fc04fc8: 0000000000000000 ...
ffff88813fc04fe8: ffff88813115aab8 (0xffff88813115aab8)
ffff88813fc04ff0: ffffffff904ecdee (instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1049 [inline])
ffff88813fc04ff0: ffffffff904ecdee (sysvec_apic_timer_interrupt+0x7e/0x90 arch/x86/kernel/apic/apic.c:1049)
ffff88813fc04ff8: ffff88813115aaa8 (0xffff88813115aaa8)
BUG: KMSAN: uninit-value in rb_next+0x200/0x210 lib/rbtree.c:505
 rb_next+0x200/0x210 lib/rbtree.c:505
 rb_erase_cached include/linux/rbtree.h:124 [inline]
 timerqueue_del+0xee/0x1a0 lib/timerqueue.c:57
 __remove_hrtimer kernel/time/hrtimer.c:1123 [inline]
 __run_hrtimer kernel/time/hrtimer.c:1771 [inline]
 __hrtimer_run_queues+0x3b7/0xe40 kernel/time/hrtimer.c:1855
 hrtimer_interrupt+0x41b/0xb10 kernel/time/hrtimer.c:1917
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1038 [inline]
 __sysvec_apic_timer_interrupt+0xa7/0x420 arch/x86/kernel/apic/apic.c:1055
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1049 [inline]
 sysvec_apic_timer_interrupt+0x7e/0x90 arch/x86/kernel/apic/apic.c:1049

Local variable set_tid.i created at:
 __do_sys_clone3 kernel/fork.c:3098 [inline]
 __se_sys_clone3+0x60/0x590 kernel/fork.c:3093
 __ia32_sys_clone3+0x6b/0xa0 kernel/fork.c:3093

CPU: 0 UID: 0 PID: 13379 Comm: syz.1.2969 Not tainted 6.14.0-syzkaller-03576-g1e1ba8d23dae #0 PREEMPT(undef) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
=====================================================


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