Re: [PATCH 5.15 000/846] 5.15.17-rc1 review

[Greg Kroah-Hartman]

On Mon, Jan 24, 2022 at 02:09:13PM -0800, Andrii Nakryiko wrote:
> On Mon, Jan 24, 2022 at 12:36 PM Holger Hoffstätte
> <holger@xxxxxxxxxxxxxxxxxxxxxx> wrote:
> >
> > On 2022-01-24 19:31, Greg Kroah-Hartman wrote:
> > > This is the start of the stable review cycle for the 5.15.17 release.
> >
> > Oh noes :(
> >
> >    DESCEND bpf/resolve_btfids
> >    MKDIR     /tmp/linux-5.15.17/tools/bpf/resolve_btfids//libbpf
> >    GEN     /tmp/linux-5.15.17/tools/bpf/resolve_btfids/libbpf/bpf_helper_defs.h
> >    MKDIR   /tmp/linux-5.15.17/tools/bpf/resolve_btfids/libbpf/staticobjs/
> >    CC      /tmp/linux-5.15.17/tools/bpf/resolve_btfids/libbpf/staticobjs/libbpf.o
> > libbpf.c: In function 'bpf_object__elf_collect':
> > libbpf.c:3038:31: error: invalid type argument of '->' (have 'GElf_Shdr' {aka 'Elf64_Shdr'})
> >   3038 |                         if (sh->sh_type != SHT_PROGBITS)
> >        |                               ^~
> > libbpf.c:3042:31: error: invalid type argument of '->' (have 'GElf_Shdr' {aka 'Elf64_Shdr'})
> >   3042 |                         if (sh->sh_type != SHT_PROGBITS)
> >        |                               ^~
> > make[4]: *** [/tmp/linux-5.15.17/tools/build/Makefile.build:97: /tmp/linux-5.15.17/tools/bpf/resolve_btfids/libbpf/staticobjs/libbpf.o] Error 1
> > make[3]: *** [Makefile:158: /tmp/linux-5.15.17/tools/bpf/resolve_btfids/libbpf/staticobjs/libbpf-in.o] Error 2
> > make[2]: *** [Makefile:44: /tmp/linux-5.15.17/tools/bpf/resolve_btfids//libbpf/libbpf.a] Error 2
> > make[1]: *** [Makefile:72: bpf/resolve_btfids] Error 2
> > make: *** [Makefile:1371: tools/bpf/resolve_btfids] Error 2
> >
> > Reverting "libbpf-validate-that-.btf-and-.btf.ext-sections-cont.patcht" aka
> > this one:
> >
> > > Andrii Nakryiko <andrii@xxxxxxxxxx>
> > >      libbpf: Validate that .BTF and .BTF.ext sections contain data
> >
> > makes it build & run fine. I looked for followups but couldn't find anything that
> > stood out, maybe the BPF folks (cc'ed) know what's missing/wrong.
> >
> 
> That small fix depends on much bigger refactoring in ad23b7238474
> ("libbpf: Use Elf64-specific types explicitly for dealing with ELF").
> I think this small fix can be dropped.
> 
> That's sort of a general rule with libbpf-related fixes, they are
> usually not that critical to backport to stable, because most users
> use/build libbpf from its Github mirror, which is always taken from
> latest bpf-next. Libbpf is also not supposed to be used with untrusted
> inputs (i.e., BPF object files) as BPF programs are loaded into the
> kernel under root.

Ok, thanks, I'll drop this from all queues now.

greg k-h