Re: [PATCH v3 1/2] kexec: return -ENOEXEC from image probe functions on mismatch

[Mukesh Pilaniya <mpilaniy@redhat.com>]

Hi Will,

On 24/08/26 7:37 pm, Will Deacon wrote:
> On Fri, Aug 21, 2026 at 07:19:57PM +0530, Mukesh Pilaniya wrote:
>> Several kexec_file_load() image probe functions return -EINVAL when
>> they do not recognize the image format.  A probe function that rejects
>> an image should return -ENOEXEC to indicate that the image is not a
>> recognized executable format.  -EINVAL implies a problem with the
>> syscall parameters, not with image recognition.
>>
>> kexec_image_probe_default() iterates through registered loaders and
>> returns the last probe's error code to the caller.  That error
>> propagates as the kexec_file_load() return value to userspace.
>> Returning -EINVAL from a probe when no loader matches is semantically
>> incorrect and misleads userspace about the nature of the failure.
>>
>> Return -ENOEXEC from all probe functions and their helpers when the
>> image format is not recognized.
>>
>> Signed-off-by: Mukesh Pilaniya <mpilaniy@redhat.com>
>> Reviewed-by: Philipp Rudo <prudo@redhat.com>
>> Reviewed-by: Pratyush Yadav <pratyush@kernel.org>
>> Reviewed-by: Bradley Morgan <include@grrlz.net>
>> ---
>>  arch/arm64/kernel/kexec_image.c   | 4 ++--
>>  arch/loongarch/kernel/kexec_efi.c | 4 ++--
>>  arch/riscv/kernel/kexec_image.c   | 4 ++--
>>  kernel/kexec_elf.c                | 4 ++--
>>  4 files changed, 8 insertions(+), 8 deletions(-)
> 
> Hmm, so after this patch, are there actually any implementations of .probe()
> that return anything other than 0 or -ENOEXEC? I couldn't spot any after
> a quick look.
> 
> Willkexec_elf_probe() can return -ENOMEM if memory allocation (kzalloc())
fails inside elf_read_phdrs(). This behavior was previously discussed in
the first patch of this series [1].

[1]
https://lore.kernel.org/all/0d7acb43-2eb4-44ec-9bfb-b89440afc605@redhat.com/#t


-- 
Regards,
Mukesh Pilaniya