blsuki: Fix grub_errno leakage in blsuki_is_default_entry()

The grub_strtol() call in blsuki_is_default_entry() can set grub_errno
to either GRUB_ERR_BAD_NUMBER or GRUB_ERR_OUT_OF_RANGE if the input
string is invalid or out of range.

This grub_errno value is currently left uncleared, which can lead to
unexpected behavior in subsequent functions that rely on checking
current state of grub_errno.

Clear grub_errno unconditionally when grub_strtol() reports error so
that we can plug the leak.

Signed-off-by: Michael Chang <mchang@suse.com>
Reviewed-by: Sudhakar Kuppusamy <sudhakar@linux.ibm.com>
Reviewed-by: Avnish Chouhan <avnish@linux.ibm.com>
Reviewed-by: Alec Brown <alec.r.brown@oracle.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
This commit is contained in:
Michael Chang 2025-11-20 14:25:50 +08:00 committed by Daniel Kiper
parent a8b2beedf6
commit 8a850f47d0

View File

@ -1360,6 +1360,10 @@ blsuki_is_default_entry (const char *def_entry, grub_blsuki_entry_t *entry, int
return true;
def_idx = grub_strtol (def_entry, &def_entry_end, 0);
/* Clear grub_errno so we can plug the leak. */
grub_errno = GRUB_ERR_NONE;
if (*def_entry_end != '\0' || def_idx < 0 || def_idx > GRUB_INT_MAX)
return false;