vpick: make a working copy of the current dname

Since we might edit the string later on by inserting NULs, which then
leads up to using an invalid dname when opening the potential chosen
directory:

[ 4316.957536] testsuite-74.sh[99]: make_choice: entry: mytree_37.0_arm64+2-3
[ 4316.957536] testsuite-74.sh[99]: make_choice: best_version: 37.0
[ 4316.957536] testsuite-74.sh[99]: make_choice: best_filename: mytree_37.0
[ 4316.957536] testsuite-74.sh[99]: Failed to open '//var/lib/machines/mytree.v/mytree_37.0': No such file or directory

Uncovered by vpick tests from TEST-74-AUX-UTILS when run on aarch64.

diff --git a/src/shared/vpick.c b/src/shared/vpick.c
index ab1f4289fcce0ac10249bdae70fc4c5f3f38570e..614708133b1245743a4a4cc119061925987cd52c 100644 (file)
--- a/src/shared/vpick.c
+++ b/src/shared/vpick.c
@@ -334,12 +334,16 @@ static int make_choice(
 
         FOREACH_ARRAY(entry, de->entries, de->n_entries) {
                 unsigned found_tries_done = UINT_MAX, found_tries_left = UINT_MAX;
-                _cleanup_free_ char *chopped = NULL;
+                _cleanup_free_ char *dname = NULL;
                 size_t found_architecture_index = SIZE_MAX;
                 const char *e;
 
+                dname = strdup((*entry)->d_name);
+                if (!dname)
+                        return log_oom_debug();
+
                 if (!isempty(filter->basename)) {
-                        e = startswith((*entry)->d_name, filter->basename);
+                        e = startswith(dname, filter->basename);
                         if (!e)
                                 continue;
 
@@ -348,20 +352,14 @@ static int make_choice(
 
                         e++;
                 } else
-                        e = (*entry)->d_name;
+                        e = dname;
 
                 if (!isempty(filter->suffix)) {
-                        const char *sfx;
-
-                        sfx = endswith(e, filter->suffix);
+                        char *sfx = endswith(e, filter->suffix);
                         if (!sfx)
                                 continue;
 
-                        chopped = strndup(e, sfx - e);
-                        if (!chopped)
-                                return log_oom_debug();
-
-                        e = chopped;
+                        *sfx = 0;
                 }
 
                 if (FLAGS_SET(flags, PICK_TRIES)) {