1 files changed, 5 insertions, 2 deletions

diff --git a/ui-patch.c b/ui-patch.c
index 8007a11..82f125b 100644
--- a/ui-patch.c
+++ b/ui-patch.c
@@ -11,13 +11,16 @@
 #include "html.h"
 #include "ui-shared.h"
 
+/* two commit hashes with two dots in between and termination */
+#define REV_RANGE_LEN 2 * GIT_MAX_HEXSZ + 3
+
 void cgit_print_patch(const char *new_rev, const char *old_rev,
                       const char *prefix)
 {
         struct rev_info rev;
         struct commit *commit;
         struct object_id new_rev_oid, old_rev_oid;
-        char rev_range[2 * 40 + 3];
+        char rev_range[REV_RANGE_LEN];
         const char *rev_argv[] = { NULL, "--reverse", "--format=email", rev_range, "--", prefix, NULL };
         int rev_argc = ARRAY_SIZE(rev_argv) - 1;
         char *patchname;
@@ -60,7 +63,7 @@ void cgit_print_patch(const char *new_rev, const char *old_rev,
         if (is_null_oid(&old_rev_oid)) {
                 memcpy(rev_range, oid_to_hex(&new_rev_oid), GIT_SHA1_HEXSZ + 1);
         } else {
-                sprintf(rev_range, "%s..%s", oid_to_hex(&old_rev_oid),
+                xsnprintf(rev_range, REV_RANGE_LEN, "%s..%s", oid_to_hex(&old_rev_oid),
                         oid_to_hex(&new_rev_oid));
         }