modprobe: do not descend into /etc/modprobe.d/DIR/. Closes 8686

Also expanded comments in recursive_action.c

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>

2 files changed, 38 insertions, 17 deletions

diff --git a/libbb/recursive_action.c b/libbb/recursive_action.c
index b5cf7c0ab..8f2b8b932 100644
--- a/libbb/recursive_action.c
+++ b/libbb/recursive_action.c
@@ -30,24 +30,37 @@ static int FAST_FUNC true_action(const char *fileName UNUSED_PARAM,
         return TRUE;
 }
 
-/* fileAction return value of 0 on any file in directory will make
- * recursive_action() return 0, but it doesn't stop directory traversal
+/* fileName is (l)stat'ed (depending on ACTION_FOLLOWLINKS[_L0]).
+ *
+ * If it is a file: fileAction in run on it, its return value is returned.
+ *
+ * In case we are in a recursive invocation (see below):
+ * normally, fileAction should return 1 (TRUE) to indicate that
+ * everything is okay and processing should continue.
+ * fileAction return value of 0 (FALSE) on any file in directory will make
+ * recursive_action() also return 0, but it doesn't stop directory traversal
  * (fileAction/dirAction will be called on each file).
  *
- * If !ACTION_RECURSE, dirAction is called on the directory and its
+ * [TODO: maybe introduce -1 to mean "stop traversal NOW and return"]
+ *
+ * If it is a directory:
+ *
+ * If !ACTION_RECURSE, dirAction is called and its
  * return value is returned from recursive_action(). No recursion.
  *
- * If ACTION_RECURSE, recursive_action() is called on each directory.
+ * If ACTION_RECURSE, directory is opened, and recursive_action() is called
+ * on each file/subdirectory.
  * If any one of these calls returns 0, current recursive_action() returns 0.
  *
+ * If !ACTION_DEPTHFIRST, dirAction is called before recurse.
+ * Return value of 0 (FALSE) is an error: prevents recursion,
+ * the warning is printed (unless ACTION_QUIET) and recursive_action() returns 0.
+ * Return value of 2 (SKIP) prevents recursion, instead recursive_action()
+ * returns 1 (TRUE, no error).
+ *
  * If ACTION_DEPTHFIRST, dirAction is called after recurse.
  * If it returns 0, the warning is printed and recursive_action() returns 0.
  *
- * If !ACTION_DEPTHFIRST, dirAction is called before we recurse.
- * Return value of 0 (FALSE) or 2 (SKIP) prevents recursion
- * into that directory, instead recursive_action() returns 0 (if FALSE)
- * or 1 (if SKIP)
- *
  * ACTION_FOLLOWLINKS mainly controls handling of links to dirs.
  * 0: lstat(statbuf). Calls fileAction on link name even if points to dir.
  * 1: stat(statbuf). Calls dirAction and optionally recurse on link to dir.
@@ -105,7 +118,7 @@ int FAST_FUNC recursive_action(const char *fileName,
 
         if (!(flags & ACTION_DEPTHFIRST)) {
                 status = dirAction(fileName, &statbuf, userData, depth);
-                if (!status)
+                if (status == FALSE)
                         goto done_nak_warn;
                 if (status == SKIP)
                         return TRUE;
@@ -121,24 +134,23 @@ int FAST_FUNC recursive_action(const char *fileName,
         status = TRUE;
         while ((next = readdir(dir)) != NULL) {
                 char *nextFile;
+                int s;
 
                 nextFile = concat_subpath_file(fileName, next->d_name);
                 if (nextFile == NULL)
                         continue;
+
                 /* process every file (NB: ACTION_RECURSE is set in flags) */
-                if (!recursive_action(nextFile, flags, fileAction, dirAction,
-                                                userData, depth + 1))
+                s = recursive_action(nextFile, flags, fileAction, dirAction,
+                                                userData, depth + 1);
+                if (s == FALSE)
                         status = FALSE;
-//              s = recursive_action(nextFile, flags, fileAction, dirAction,
-//                                              userData, depth + 1);
                 free(nextFile);
-//#define RECURSE_RESULT_ABORT 3
+//#define RECURSE_RESULT_ABORT -1
 //              if (s == RECURSE_RESULT_ABORT) {
 //                      closedir(dir);
 //                      return s;
 //              }
-//              if (s == FALSE)
-//                      status = FALSE;
         }
         closedir(dir);
 
diff --git a/modutils/modprobe.c b/modutils/modprobe.c
index c82eaa8d8..51ede9204 100644
--- a/modutils/modprobe.c
+++ b/modutils/modprobe.c
@@ -252,6 +252,15 @@ static int FAST_FUNC config_file_action(const char *filename,
         if (base[0] == '.')
                 goto error;
 
+        /* "man modprobe.d" from kmod version 22 suggests
+         * that we shouldn't recurse into /etc/modprobe.d/dir/
+         * _subdirectories_:
+         */
+        if (depth > 1)
+                return SKIP; /* stop recursing */
+//TODO: instead, can use dirAction in recursive_action() to SKIP dirs
+//on depth == 1 level. But that's more code...
+
         /* In dir recursion, skip files that do not end with a ".conf"
          * depth==0: read_config("modules.{symbols,alias}") must work,
          * "include FILE_NOT_ENDING_IN_CONF" must work too.