=====================================================
BUG: KMSAN: uninit-value in strnchr+0x90/0xd0 lib/string.c:388
 strnchr+0x90/0xd0 lib/string.c:388
 bpf_bprintf_prepare+0x1c2/0x23c0 kernel/bpf/helpers.c:829
 ____bpf_trace_printk kernel/trace/bpf_trace.c:385 [inline]
 bpf_trace_printk+0xec/0x3e0 kernel/trace/bpf_trace.c:375
 ___bpf_prog_run+0x13fe/0xe0f0 kernel/bpf/core.c:1986
 __bpf_prog_run256+0xb5/0xe0 kernel/bpf/core.c:2226
 bpf_dispatcher_nop_func include/linux/bpf.h:1231 [inline]
 __bpf_prog_run include/linux/filter.h:651 [inline]
 bpf_prog_run include/linux/filter.h:658 [inline]
 bpf_test_run+0x499/0xc30 net/bpf/test_run.c:423
 bpf_prog_test_run_skb+0x14ea/0x1f20 net/bpf/test_run.c:1056
 bpf_prog_test_run+0x6b7/0xad0 kernel/bpf/syscall.c:4107
 __sys_bpf+0x649/0xd70 kernel/bpf/syscall.c:5475
 __do_sys_bpf kernel/bpf/syscall.c:5561 [inline]
 __se_sys_bpf kernel/bpf/syscall.c:5559 [inline]
 __x64_sys_bpf+0xa0/0xe0 kernel/bpf/syscall.c:5559
 do_syscall_64+0xd5/0x1f0
 entry_SYSCALL_64_after_hwframe+0x6d/0x75

Local variable stack created at:
 __bpf_prog_run256+0x45/0xe0 kernel/bpf/core.c:2226
 bpf_dispatcher_nop_func include/linux/bpf.h:1231 [inline]
 __bpf_prog_run include/linux/filter.h:651 [inline]
 bpf_prog_run include/linux/filter.h:658 [inline]
 bpf_test_run+0x499/0xc30 net/bpf/test_run.c:423

CPU: 1 PID: 12159 Comm: syz-executor.2 Not tainted 6.8.0-syzkaller-01185-g855684c7d938 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/29/2024
=====================================================