If descstrp->length is less than 2 this will result in underflow in
"descstrp->length / 2 - 1" math. Let's fix the check to make sure the
value is sufficient.
Signed-off-by: Jamie <volticks@gmail.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
An incorrect length field is used for buffer allocation. This leads to
grub_utf16_to_utf8() receiving an incorrect/different length and possibly
causing OOB write. This makes sure to use the correct length.
Fixes: CVE-2025-61661
Reported-by: Jamie <volticks@gmail.com>
Signed-off-by: Jamie <volticks@gmail.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
Disable the -Wadress-of-packaed-member diagnostic for the
grub_usb_get_string function since the result is false postive. The
descstrp->str is found to be aligned in the buffer allocated for 'struct
grub_usb_desc_str'.
[ 229s] ../../grub-core/commands/usbtest.c: In function 'grub_usb_get_string':
[ 229s] ../../grub-core/commands/usbtest.c:104:58: error: taking address of packed member of 'struct grub_usb_desc_str' may result in an unaligned pointer value [-Werror=address-of-packed-member]
[ 229s] 104 | *grub_utf16_to_utf8 ((grub_uint8_t *) *string, descstrp->str,
[ 229s] | ~~~~~~~~^~~~~
Signed-off-by: Michael Chang <mchang@suse.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>