syzbot

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BUG: KMSAN: uninit-value in vsnprintf+0x15d9/0x1b30 lib/vsprintf.c:2911
 vsnprintf+0x15d9/0x1b30 lib/vsprintf.c:2911
 vprintk_store+0x34e/0x1460 kernel/printk/printk.c:2255
 vprintk_emit+0x277/0xb70 kernel/printk/printk.c:2402
 vprintk_default+0x3f/0x50 kernel/printk/printk.c:2441
 vprintk+0x36/0x50 kernel/printk/printk_safe.c:82
 __warn_printf lib/bug.c:190 [inline]
 __report_bug+0xa53/0xe80 lib/bug.c:244
 report_bug_entry+0x17c/0x220 lib/bug.c:269
 handle_bug+0xe1/0x230 arch/x86/kernel/traps.c:430
 exc_invalid_op+0x1f/0x50 arch/x86/kernel/traps.c:489
 asm_exc_invalid_op+0x1f/0x30 arch/x86/include/asm/idtentry.h:616
 reg_bounds_sanity_check+0x577/0x1450 kernel/bpf/verifier.c:2742
 reg_set_min_max+0x3be/0x450 kernel/bpf/verifier.c:16577
 check_cond_jmp_op+0x3a87/0x5380 kernel/bpf/verifier.c:17021
 do_check_insn kernel/bpf/verifier.c:20446 [inline]
 do_check+0x23ef/0x16a50 kernel/bpf/verifier.c:20586
 do_check_common+0x2217/0x3370 kernel/bpf/verifier.c:23870
 do_check_main kernel/bpf/verifier.c:23953 [inline]
 bpf_check+0x1e78c/0x27610 kernel/bpf/verifier.c:25260
 bpf_prog_load+0x2af6/0x3100 kernel/bpf/syscall.c:3088
 __sys_bpf+0x7df/0xeb0 kernel/bpf/syscall.c:6164
 __do_sys_bpf kernel/bpf/syscall.c:6274 [inline]
 __se_sys_bpf kernel/bpf/syscall.c:6272 [inline]
 __x64_sys_bpf+0xa4/0xf0 kernel/bpf/syscall.c:6272
 x64_sys_call+0x31c3/0x3e70 arch/x86/include/generated/asm/syscalls_64.h:322
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xd3/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Uninit was stored to memory at:
 vsnprintf+0x15d2/0x1b30 lib/vsprintf.c:-1
 vprintk_store+0x34e/0x1460 kernel/printk/printk.c:2255
 vprintk_emit+0x277/0xb70 kernel/printk/printk.c:2402
 vprintk_default+0x3f/0x50 kernel/printk/printk.c:2441
 vprintk+0x36/0x50 kernel/printk/printk_safe.c:82
 __warn_printf lib/bug.c:190 [inline]
 __report_bug+0xa53/0xe80 lib/bug.c:244
 report_bug_entry+0x17c/0x220 lib/bug.c:269
 handle_bug+0xe1/0x230 arch/x86/kernel/traps.c:430
 exc_invalid_op+0x1f/0x50 arch/x86/kernel/traps.c:489
 asm_exc_invalid_op+0x1f/0x30 arch/x86/include/asm/idtentry.h:616

Local variable run_ctx.i created at:
 __bpf_trace_run kernel/trace/bpf_trace.c:2063 [inline]
 bpf_trace_run4+0xdf/0x590 kernel/trace/bpf_trace.c:2118
 __bpf_trace_sched_switch+0x221/0x290 include/trace/events/sched.h:220

CPU: 1 UID: 0 PID: 13870 Comm: syz.7.2582 Tainted: G        W    L      syzkaller #0 PREEMPT(none) 
Tainted: [W]=WARN, [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
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