Re: [Linux-kernel-mentees] [PATCH v2] bpf: Fix NULL pointer dereference in __btf_resolve_helper_id()

From: Andrii Nakryiko
Date: Tue Jul 14 2020 - 00:38:14 EST


On Mon, Jul 13, 2020 at 6:29 PM Peilin Ye <yepeilin.cs@xxxxxxxxx> wrote:
>
> Prevent __btf_resolve_helper_id() from dereferencing `btf_vmlinux`
> as NULL. This patch fixes the following syzbot bug:
>
> https://syzkaller.appspot.com/bug?id=5edd146856fd513747c1992442732e5a0e9ba355
>
> Reported-by: syzbot+ee09bda7017345f1fbe6@xxxxxxxxxxxxxxxxxxxxxxxxx
> Signed-off-by: Peilin Ye <yepeilin.cs@xxxxxxxxx>
> ---
> Thank you for reviewing my patch! I am new to Linux kernel development; would
> the log message and errno be appropriate for this case?

I think it's good enough, thanks for the fix.

Acked-by: Andrii Nakryiko <andriin@xxxxxx>

>
> Change in v2:
> - Split NULL and IS_ERR cases.
>
> kernel/bpf/btf.c | 5 +++++
> 1 file changed, 5 insertions(+)
>

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