Re: [PATCH bpf] bpf: Fix netns reference imbalance in conntrack kfuncs

> The kernel reported:
>
>   Oops: general protection fault, probably for non-canonical address
>   KASAN: null-ptr-deref in range [0x00000000000000e8-0x00000000000000ef]
>   RIP: 0010:bpf_prog_test_run_xdp+0x52c/0x1700
>   Call Trace:
>    __sys_bpf+0x1662/0x50c0
>    __x64_sys_bpf+0x73/0xb0
>    do_syscall_64+0xf9/0x540
>    entry_SYSCALL_64_after_hwframe+0x77/0x7f
>   Kernel panic - not syncing: Fatal exception

This isn't a bug, but could the crash trace be clearer about its
connection to the fix? The trace shows only BPF test-run frames
with no netfilter or conntrack function names visible.

The chain is reconstructible - the extra put_net() frees the
caller's netns, loopback_dev becomes NULL, and bpf_prog_test_run_xdp()
then dereferences it - but a reader has to derive this themselves.

Would it help to add a sentence connecting the trace to the fix, or
include a Reported-by: or Closes: tag for the original report?


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