Fix infinite loop and reallocate if too many modules.

[oweals/busybox.git] / lsmod.c

diff --git a/lsmod.c b/lsmod.c
index 8251705de62d6fc0bab6c494c6224166c8a3e033..76ed2fdd8f0ea2d999e3be9d1f0f69103933beee 100644 (file)
--- a/lsmod.c
+++ b/lsmod.c
@@ -52,8 +52,7 @@ struct module_info
 };
 
 
-int query_module(const char *name, int which, void *buf, size_t bufsize,
-                size_t *ret);
+int query_module(const char *name, int which, void *buf, size_t bufsize, size_t *ret);
 
 /* Values for query_module's which.  */
 static const int QM_MODULES = 1;
@@ -70,19 +69,36 @@ static const int NEW_MOD_VISITED = 8;
 static const int NEW_MOD_USED_ONCE = 16;
 static const int NEW_MOD_INITIALIZING = 64;
 
+static int my_query_module(const char *name, int which, void **buf,
+               size_t *bufsize, size_t *ret)
+{
+       int my_ret;
+
+       my_ret = query_module(name, which, *buf, *bufsize, ret);
+
+       if (my_ret == -1 && errno == ENOSPC) {
+               *buf = xrealloc(*buf, *ret);
+               *bufsize = *ret;
+
+               my_ret = query_module(name, which, *buf, *bufsize, ret);
+       }
+
+       return my_ret;
+}
 
 extern int lsmod_main(int argc, char **argv)
 {
        struct module_info info;
        char *module_names, *mn, *deps, *dn;
-       size_t bufsize, nmod, count, i, j;
+       size_t bufsize, depsize, nmod, count, i, j;
 
        module_names = xmalloc(bufsize = 256);
-       deps = xmalloc(bufsize);
-       if (query_module(NULL, QM_MODULES, module_names, bufsize, &nmod)) {
+       if (my_query_module(NULL, QM_MODULES, (void **)&module_names, &bufsize,
+                               &nmod)) {
                perror_msg_and_die("QM_MODULES");
        }
 
+       deps = xmalloc(depsize = 256);
        printf("Module                  Size  Used by\n");
        for (i = 0, mn = module_names; i < nmod; mn += strlen(mn) + 1, i++) {
                if (query_module(mn, QM_INFO, &info, sizeof(info), &count)) {
@@ -93,15 +109,12 @@ extern int lsmod_main(int argc, char **argv)
                        /* else choke */
                        perror_msg_and_die("module %s: QM_INFO", mn);
                }
-               while (query_module(mn, QM_REFS, deps, bufsize, &count)) {
+               if (my_query_module(mn, QM_REFS, (void **)&deps, &depsize, &count)) {
                        if (errno == ENOENT) {
                                /* The module was removed out from underneath us. */
                                continue;
                        }
-                       if (errno != ENOSPC) {
-                               error_msg_and_die("module %s: QM_REFS", mn);
-                       }
-                       deps = xrealloc(deps, bufsize = count);
+                       perror_msg_and_die("module %s: QM_REFS", mn);
                }
                printf("%-20s%8lu%4ld ", mn, info.size, info.usecount);
                if (info.flags & NEW_MOD_DELETED)