make the dynamic linker find its path file relative to its own location

[musl] / src / ldso / dynlink.c

diff --git a/src/ldso/dynlink.c b/src/ldso/dynlink.c
index ff5b738..1d5e297 100644 (file)
--- a/src/ldso/dynlink.c
+++ b/src/ldso/dynlink.c
@@ -483,7 +483,26 @@ static struct dso *load_library(const char *name)
                if (fd < 0 && env_path) fd = path_open(name, env_path, buf, sizeof buf);
                if (fd < 0) {
                        if (!sys_path) {
-                               FILE *f = fopen(ETC_LDSO_PATH, "rbe");
+                               char *prefix = 0;
+                               size_t prefix_len;
+                               if (ldso->name[0]=='/') {
+                                       char *s, *t, *z;
+                                       for (s=t=z=ldso->name; *s; s++)
+                                               if (*s=='/') z=t, t=s;
+                                       prefix_len = z-ldso->name;
+                                       if (prefix_len < PATH_MAX)
+                                               prefix = ldso->name;
+                               }
+                               if (!prefix) {
+                                       prefix = "";
+                                       prefix_len = 0;
+                               }
+                               char etc_ldso_path[prefix_len + 1
+                                       + sizeof "/etc/ld-musl-" LDSO_ARCH ".path"];
+                               snprintf(etc_ldso_path, sizeof etc_ldso_path,
+                                       "%.*s/etc/ld-musl-" LDSO_ARCH ".path",
+                                       (int)prefix_len, prefix);
+                               FILE *f = fopen(etc_ldso_path, "rbe");
                                if (f) {
                                        if (getdelim(&sys_path, (size_t[1]){0}, 0, f) <= 0) {
                                                free(sys_path);