more readlink buffer size handling

diff --git a/libudev/libudev-device.c b/libudev/libudev-device.c
index b3b6a63114106f973327b5a594762df6c5bdc293..400354539b4d849c9454e4c435a27526302aa181 100644 (file)
--- a/libudev/libudev-device.c
+++ b/libudev/libudev-device.c
@@ -222,12 +222,11 @@ int udev_device_read_db(struct udev_device *udev_device)
                char *next;
 
                target_len = readlink(filename, target, sizeof(target));
-               if (target_len > 0)
-                       target[target_len] = '\0';
-               else {
-                       dbg(udev_device->udev, "error reading db link %s: %m\n", filename);
+               if (target_len <= 0 || target_len == sizeof(target)) {
+                       info(udev_device->udev, "error reading db link %s: %m\n", filename);
                        return -1;
                }
+               target[target_len] = '\0';
 
                next = strchr(target, ' ');
                if (next != NULL) {
@@ -1095,16 +1094,18 @@ const char *udev_device_get_sysattr_value(struct udev_device *udev_device, const
                        goto out;
 
                len = readlink(path, target, sizeof(target));
-               if (len > 0) {
-                       target[len] = '\0';
-                       pos = strrchr(target, '/');
-                       if (pos != NULL) {
-                               pos = &pos[1];
-                               dbg(udev_device->udev, "cache '%s' with link value '%s'\n", sysattr, pos);
-                               list_entry = udev_list_entry_add(udev_device->udev, &udev_device->sysattr_list, sysattr, pos, 0, 0);
-                               val = udev_list_entry_get_value(list_entry);
-                       }
+               if (len <= 0 || len == sizeof(target))
+                       goto out;
+               target[len] = '\0';
+
+               pos = strrchr(target, '/');
+               if (pos != NULL) {
+                       pos = &pos[1];
+                       dbg(udev_device->udev, "cache '%s' with link value '%s'\n", sysattr, pos);
+                       list_entry = udev_list_entry_add(udev_device->udev, &udev_device->sysattr_list, sysattr, pos, 0, 0);
+                       val = udev_list_entry_get_value(list_entry);
                }
+
                goto out;
        }
 

diff --git a/libudev/libudev-queue.c b/libudev/libudev-queue.c
index f06c9e8a7a3caaeced9653bc7678f50a2adb0fa5..5a4a3dc095ccf236d106b9ebfba23a58990cdf29 100644 (file)
--- a/libudev/libudev-queue.c
+++ b/libudev/libudev-queue.c
@@ -488,7 +488,7 @@ struct udev_list_entry *udev_queue_get_failed_list_entry(struct udev_queue *udev
                s = syspath;
                l = util_strpcpyl(&s, sizeof(syspath), udev_get_sys_path(udev_queue->udev), NULL);
                len = readlinkat(dirfd(dir), dent->d_name, s, l);
-               if (len < 0 || (size_t)len >= l)
+               if (len <= 0 || (size_t)len == l)
                        continue;
                s[len] = '\0';
                dbg(udev_queue->udev, "found '%s' [%s]\n", syspath, dent->d_name);

diff --git a/udev/udev-node.c b/udev/udev-node.c
index ceb1d52ea7f7bf2c794696b057018ad5fd5e68d4..5c1b04b86c88bb150899c8c8e46d121379538c04 100644 (file)
--- a/udev/udev-node.c
+++ b/udev/udev-node.c
@@ -163,8 +163,8 @@ static int node_symlink(struct udev *udev, const char *node, const char *slink)
                        int len;
 
                        dbg(udev, "found existing symlink '%s'\n", slink);
-                       len = readlink(slink, buf, sizeof(buf) - 1);
-                       if (len > 0) {
+                       len = readlink(slink, buf, sizeof(buf));
+                       if (len > 0 && len < (int)sizeof(buf)) {
                                buf[len] = '\0';
                                if (strcmp(target, buf) == 0) {
                                        info(udev, "preserve already existing symlink '%s' to '%s'\n",

diff --git a/udev/udev-watch.c b/udev/udev-watch.c
index 7135d9f4721c7cfd74bbb61bf24592d138fd6a0c..5fa60101c46ad63cb99e444d4b103c6f5d33217c 100644 (file)
--- a/udev/udev-watch.c
+++ b/udev/udev-watch.c
@@ -81,7 +81,7 @@ void udev_watch_restore(struct udev *udev)
                        s = device;
                        l = util_strpcpy(&s, sizeof(device), udev_get_sys_path(udev));
                        len = readlinkat(dirfd(dir), ent->d_name, s, l);
-                       if (len <= 0 || len >= (ssize_t)l)
+                       if (len <= 0 || len == (ssize_t)l)
                                goto unlink;
                        s[len] = '\0';
 
@@ -173,7 +173,7 @@ struct udev_device *udev_watch_lookup(struct udev *udev, int wd)
        s = majmin;
        l = util_strpcpy(&s, sizeof(majmin), udev_get_sys_path(udev));
        len = readlink(filename, s, l);
-       if (len < 0 || (size_t)len >= l)
+       if (len <= 0 || (size_t)len == l)
                return NULL;
        s[len] = '\0';