1 files changed, 5 insertions, 1 deletions

diff --git a/archival/libarchive/unsafe_prefix.c b/archival/libarchive/unsafe_prefix.c
index 33e487bf9..667081195 100644
--- a/archival/libarchive/unsafe_prefix.c
+++ b/archival/libarchive/unsafe_prefix.c
@@ -14,7 +14,11 @@ const char* FAST_FUNC strip_unsafe_prefix(const char *str)
                         cp++;
                         continue;
                 }
-                if (is_prefixed_with(cp, "/../"+1)) {
+                /* We are called lots of times.
+                 * is_prefixed_with(cp, "../") is slower than open-coding it,
+                 * with minimal code growth (~few bytes).
+                 */
+                if (cp[0] == '.' && cp[1] == '.' && cp[2] == '/') {
                         cp += 3;
                         continue;
                 }