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

On Mon, Jul 13, 2020 at 6:29 PM Peilin Ye [off-list ref] 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@syzkaller.appspotmail.com
Signed-off-by: Peilin Ye <redacted>
---
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 <redacted>

Change in v2:
    - Split NULL and IS_ERR cases.

 kernel/bpf/btf.c | 5 +++++
 1 file changed, 5 insertions(+)

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