On Tue, Mar 11, 2025 at 8:03 PM Chen Linxuan <chenlinxuan@xxxxxxxxxx> wrote:
>
> Greg KH <gregkh@xxxxxxxxxxxxxxxxxxx> 于2025年3月11日周二 19:14写道：
> >
> > On Tue, Mar 11, 2025 at 06:05:55PM +0800, Chen Linxuan wrote:
> > > Backport of a similar change from commit 5ac9b4e935df ("lib/buildid:
> > > Handle memfd_secret() files in build_id_parse()") to address an issue
> > > where accessing secret memfd contents through build_id_parse() would
> > > trigger faults.
> > >
> > > Original report and repro can be found in [0].
> > >
> > > [0] https://lore.kernel.org/bpf/ZwyG8Uro%2FSyTXAni@ly-workstation/
> > >
> > > This repro will cause BUG: unable to handle kernel paging request in
> > > build_id_parse in 5.15/6.1/6.6.
> > >
> > > Some other discussions can be found in [1].
> > >
> > > [1] https://lore.kernel.org/bpf/20241104175256.2327164-1-jolsa@xxxxxxxxxx/T/#u
> > >
> > > Cc: stable@xxxxxxxxxxxxxxx
> > > Fixes: 88a16a130933 ("perf: Add build id data in mmap2 event")
> > > Signed-off-by: Chen Linxuan <chenlinxuan@xxxxxxxxxx>
> >
> > You dropped all the original signed-off-by and changelog text. Just
>
> The original commit is based on commit de3ec364c3c3 ("lib/buildid: add
> single folio-based file reader abstraction"). `git cherry-pick` result lots of
> conflicts. So I rewrite same logic on old code.
>
Yep, for the purpose of fixing the issue, I wouldn't try to backport
my folio-based changes to lib/buildid. What you are doing here (an
equivalent direct check for secretmem) makes sense to me.
Acked-by: Andrii Nakryiko <andrii@xxxxxxxxxx>
> > provide a backport with all of the original information, and then if you
> > had to do something "different", put that in the signed-off-by area.
> > THere are loads of examples on the list for how that was done.
>
> Do you means that I should:
>
> 1. Run git cherry-pick 5ac9b4e935df on stable branches;
> 2. Resolve conflicts by drop all changes then apply changes
> as I send in this email;
> 3. Note why content of this patch is different from the original
> one after original signed-off-by area, but before the --- separator.
>
> I am not familiar with contributing to stable kernel tree.
> Sorry for bothering.
>
> >
> > thanks,
> >
> > greg k-h
> >
> >
