Re: [PATCH 6.1.y 2/7] binfmt_elf: Support segments with 0 filesz and misaligned starts

[Sasha Levin <sashal@kernel.org>]

[ Sasha's backport helper bot ]

Hi,

✅ All tests passed successfully. No issues detected.
No action required from the submitter.

The upstream commit SHA1 provided is correct: 585a018627b4d7ed37387211f667916840b5c5ea

WARNING: Author mismatch between patch and upstream commit:
Backport author: Kang Wenlin<wenlin.kang@windriver.com>
Commit author: Eric W. Biederman<ebiederm@xmission.com>

Status in newer kernel trees:
6.13.y | Present (exact SHA1)
6.12.y | Present (exact SHA1)
6.6.y | Not found

Note: The patch differs from the upstream commit:
---
1:  585a018627b4d ! 1:  f14beae673802 binfmt_elf: Support segments with 0 filesz and misaligned starts
    @@ Metadata
      ## Commit message ##
         binfmt_elf: Support segments with 0 filesz and misaligned starts
     
    +    commit 585a018627b4d7ed37387211f667916840b5c5ea upstream
    +
         Implement a helper elf_load() that wraps elf_map() and performs all
         of the necessary work to ensure that when "memsz > filesz" the bytes
         described by "memsz > filesz" are zeroed.
    @@ Commit message
         Signed-off-by: Sebastian Ott <sebott@redhat.com>
         Link: https://lore.kernel.org/r/20230929032435.2391507-1-keescook@chromium.org
         Signed-off-by: Kees Cook <keescook@chromium.org>
    +    Signed-off-by: Wenlin Kang <wenlin.kang@windriver.com>
     
      ## fs/binfmt_elf.c ##
     @@ fs/binfmt_elf.c: static struct linux_binfmt elf_format = {
    @@ fs/binfmt_elf.c: static int load_elf_binary(struct linux_binprm *bprm)
      
     -		if (unlikely (elf_brk > elf_bss)) {
     -			unsigned long nbyte;
    --
    +-	            
     -			/* There was a PT_LOAD segment with p_memsz > p_filesz
     -			   before this one. Map anonymous pages, if needed,
     -			   and clear the area.  */
---

Results of testing on various branches:

| Branch                    | Patch Apply | Build Test |
|---------------------------|-------------|------------|
| stable/linux-6.6.y        |  Success    |  Success   |