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BUG: KMSAN: uninit-value in copy_from_kernel_nofault+0x2f3/0x610 mm/maccess.c:43
 copy_from_kernel_nofault+0x2f3/0x610 mm/maccess.c:43
 bpf_bprintf_prepare+0x1e0d/0x23c0 kernel/bpf/helpers.c:935
 ____bpf_snprintf kernel/bpf/helpers.c:1061 [inline]
 bpf_snprintf+0x141/0x360 kernel/bpf/helpers.c:1045
 ___bpf_prog_run+0x13fe/0xe0f0 kernel/bpf/core.c:2015
 __bpf_prog_run288+0xc5/0xf0 kernel/bpf/core.c:2257
 bpf_dispatcher_nop_func include/linux/bpf.h:1290 [inline]
 __bpf_prog_run include/linux/filter.h:701 [inline]
 bpf_prog_run include/linux/filter.h:708 [inline]
 bpf_test_run+0x546/0xd20 net/bpf/test_run.c:434
 bpf_prog_test_run_skb+0x18fa/0x25a0 net/bpf/test_run.c:1093
 bpf_prog_test_run+0x5e5/0xa30 kernel/bpf/syscall.c:4407
 __sys_bpf+0x6aa/0xd90 kernel/bpf/syscall.c:5813
 __do_sys_bpf kernel/bpf/syscall.c:5902 [inline]
 __se_sys_bpf kernel/bpf/syscall.c:5900 [inline]
 __x64_sys_bpf+0xa0/0xe0 kernel/bpf/syscall.c:5900
 x64_sys_call+0x329c/0x3c30 arch/x86/include/generated/asm/syscalls_64.h:322
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xcd/0x1e0 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Local variable refs created at:
 free_pages_and_swap_cache+0x63/0xa40 mm/swap_state.c:318
 __tlb_batch_free_encoded_pages mm/mmu_gather.c:136 [inline]
 tlb_batch_pages_flush mm/mmu_gather.c:149 [inline]
 tlb_flush_mmu_free mm/mmu_gather.c:389 [inline]
 tlb_flush_mmu+0x7b4/0xd20 mm/mmu_gather.c:396

Bytes 0-3 of 4 are uninitialized
Memory access of size 4 starts at ffff8881359179a8

CPU: 1 UID: 0 PID: 9710 Comm: syz.3.1119 Not tainted 6.14.0-rc5-syzkaller-00234-gb7c90e3e717a #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
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