syzbot

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BUG: KMSAN: kernel-infoleak in instrument_copy_to_user include/linux/instrumented.h:114 [inline]
BUG: KMSAN: kernel-infoleak in __copy_to_user_inatomic include/linux/uaccess.h:125 [inline]
BUG: KMSAN: kernel-infoleak in copy_to_user_nofault+0x129/0x1f0 mm/maccess.c:149
 instrument_copy_to_user include/linux/instrumented.h:114 [inline]
 __copy_to_user_inatomic include/linux/uaccess.h:125 [inline]
 copy_to_user_nofault+0x129/0x1f0 mm/maccess.c:149
 ____bpf_probe_write_user kernel/trace/bpf_trace.c:349 [inline]
 bpf_probe_write_user+0x104/0x180 kernel/trace/bpf_trace.c:327
 ___bpf_prog_run+0x13fe/0xe0f0 kernel/bpf/core.c:1997
 __bpf_prog_run64+0xb5/0xe0 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_kfree+0x29/0x40 include/trace/events/kmem.h:94
 trace_kfree include/trace/events/kmem.h:94 [inline]
 kfree+0x6a5/0xa30 mm/slub.c:4377
 vfs_writev+0x12bf/0x1450 fs/read_write.c:978
 do_writev+0x251/0x5c0 fs/read_write.c:1018
 __do_sys_writev fs/read_write.c:1091 [inline]
 __se_sys_writev fs/read_write.c:1088 [inline]
 __x64_sys_writev+0x98/0xe0 fs/read_write.c:1088
 do_syscall_64+0xd5/0x1f0
 entry_SYSCALL_64_after_hwframe+0x72/0x7a

Local variable stack created at:
 __bpf_prog_run64+0x45/0xe0 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

Bytes 0-7 of 8 are uninitialized
Memory access of size 8 starts at ffff888121ec7ae8
Data copied to user address 00000000ffffffff

CPU: 1 PID: 4779 Comm: dhcpcd Not tainted 6.9.0-rc3-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024
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