:: commit 75b8b74ffcb486c1d97ec0ce4c1d13e7577c4cdb

Mintsuki <mintsuki@protonmail.com> — 2026-02-08 12:28

parents: 7f4789578f

host/limine: Guard secondary GPT nuke against alternate_lba underflow

diff --git a/host/limine.c b/host/limine.c
index 4700f3d5..6ae3104b 100644
--- a/host/limine.c
+++ b/host/limine.c
@@ -883,8 +883,11 @@ static int bios_install(int argc, char *argv[]) {
         }
 
         // ... nuke secondary GPT.
-        for (size_t i = 0; i < 33; i++) {
-            device_write(empty_lba, ((ENDSWAP(gpt_header.alternate_lba) - 32) + i) * lb_size, lb_size);
+        uint64_t alt_lba = ENDSWAP(gpt_header.alternate_lba);
+        if (alt_lba >= 32) {
+            for (size_t i = 0; i < 33; i++) {
+                device_write(empty_lba, (alt_lba - 32 + i) * lb_size, lb_size);
+            }
         }
 
         free(empty_lba);
tab: 248 wrap: offon