=====================================================
BUG: KMSAN: uninit-value in strnchr+0x90/0xd0 lib/string.c:387
 strnchr+0x90/0xd0 lib/string.c:387
 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:1997
 __bpf_prog_run32+0xb2/0xe0 kernel/bpf/core.c:2236
 bpf_dispatcher_nop_func include/linux/bpf.h:1234 [inline]
 __bpf_prog_run include/linux/filter.h:657 [inline]
 bpf_prog_run include/linux/filter.h:664 [inline]
 __bpf_trace_run kernel/trace/bpf_trace.c:2381 [inline]
 bpf_trace_run2+0x116/0x300 kernel/trace/bpf_trace.c:2420
 __bpf_trace_rss_stat+0x27/0x40 include/trace/events/kmem.h:384
 trace_rss_stat include/trace/events/kmem.h:384 [inline]
 mm_trace_rss_stat mm/memory.c:180 [inline]
 add_mm_counter include/linux/mm.h:2603 [inline]
 do_anonymous_page mm/memory.c:4478 [inline]
 do_pte_missing mm/memory.c:3878 [inline]
 handle_pte_fault mm/memory.c:5300 [inline]
 __handle_mm_fault mm/memory.c:5441 [inline]
 handle_mm_fault+0xc66f/0xce10 mm/memory.c:5606
 faultin_page mm/gup.c:958 [inline]
 __get_user_pages+0xa59/0x2c20 mm/gup.c:1257
 populate_vma_page_range mm/gup.c:1697 [inline]
 __mm_populate+0x5f8/0x990 mm/gup.c:1800
 mm_populate include/linux/mm.h:3413 [inline]
 __do_sys_mlockall mm/mlock.c:777 [inline]
 __se_sys_mlockall+0x5d1/0x720 mm/mlock.c:753
 __x64_sys_mlockall+0x48/0x60 mm/mlock.c:753
 x64_sys_call+0x35a2/0x3b50 arch/x86/include/generated/asm/syscalls_64.h:152
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xcf/0x1e0 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Local variable stack created at:
 __bpf_prog_run32+0x43/0xe0 kernel/bpf/core.c:2236
 bpf_dispatcher_nop_func include/linux/bpf.h:1234 [inline]
 __bpf_prog_run include/linux/filter.h:657 [inline]
 bpf_prog_run include/linux/filter.h:664 [inline]
 __bpf_trace_run kernel/trace/bpf_trace.c:2381 [inline]
 bpf_trace_run2+0x116/0x300 kernel/trace/bpf_trace.c:2420

CPU: 1 PID: 9646 Comm: syz-executor.0 Not tainted 6.9.0-syzkaller-02707-g614da38e2f7a #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/02/2024
=====================================================