From 8a850f47d070a19bac355807f16461bf52807510 Mon Sep 17 00:00:00 2001 From: Michael Chang Date: Thu, 20 Nov 2025 14:25:50 +0800 Subject: [PATCH] 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 Reviewed-by: Sudhakar Kuppusamy Reviewed-by: Avnish Chouhan Reviewed-by: Alec Brown Reviewed-by: Daniel Kiper --- grub-core/commands/blsuki.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/grub-core/commands/blsuki.c b/grub-core/commands/blsuki.c index d089dec62..a169e3f59 100644 --- a/grub-core/commands/blsuki.c +++ b/grub-core/commands/blsuki.c @@ -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; -- 2.47.3