Hi,
> More to the point, you haven't explained how to work around the fact
> that simply inverting the chmod/chown (or any variation of that) doesn't
> remove the race condition - just moves it between the user or group.
below you find a patch that should fix the specific issue - I just am
not sure that it interacts nicely with the rest of udev. Also, I haven't
tried it, not even compiled it.
Florian
diff --git a/udev/udev-node.c b/udev/udev-node.c
index 03ab0ea..d73bc6c 100644
--- a/udev/udev-node.c
+++ b/udev/udev-node.c
@@ -88,11 +88,11 @@ int udev_node_mknod(struct udev_device *dev, const char *file, dev_t devnum, mod
util_strscpyl(file_tmp, sizeof(file_tmp), file, TMP_FILE_EXT, NULL);
unlink(file_tmp);
udev_selinux_setfscreatecon(udev, file_tmp, mode);
- err = mknod(file_tmp, mode, devnum);
+ err = mknod(file_tmp, 0, devnum);
udev_selinux_resetfscreatecon(udev);
if (err != 0) {
err(udev, "mknod(%s, %#o, %u, %u) failed: %m\n",
- file_tmp, mode, major(devnum), minor(devnum));
+ file_tmp, 0, major(devnum), minor(devnum));
goto exit;
}
err = rename(file_tmp, file);
@@ -102,17 +102,33 @@ int udev_node_mknod(struct udev_device *dev, const char *file, dev_t devnum, mod
}
}
} else {
- info(udev, "mknod(%s, %#o, (%u,%u))\n", file, mode, major(devnum), minor(devnum));
+ info(udev, "mknod(%s, %#o, (%u,%u))\n", file, 0, major(devnum), minor(devnum));
udev_selinux_setfscreatecon(udev, file, mode);
- err = mknod(file, mode, devnum);
+ err = mknod(file, 0, devnum);
udev_selinux_resetfscreatecon(udev);
if (err != 0) {
- err(udev, "mknod(%s, %#o, (%u,%u) failed: %m\n", file, mode, major(devnum), minor(devnum));
+ err(udev, "mknod(%s, %#o, (%u,%u)) failed: %m\n", file, 0, major(devnum), minor(devnum));
goto exit;
}
}
- if (!preserve || stats.st_mode != mode) {
+ if (!preserve || stats.st_mode != mode || stats.st_uid != uid || stats.st_gid != gid) {
+ if (!preserve || stats.st_uid != uid || stats.st_gid != gid) {
+ info(udev, "chmod(%s, %#o)\n", file, 0);
+ err = chmod(file, 0);
+ if (err != 0) {
+ err(udev, "chmod(%s, %#o) failed: %m\n", file, 0);
+ goto exit;
+ }
+
+ info(udev, "chown(%s, %u, %u)\n", file, uid, gid);
+ err = chown(file, uid, gid);
+ if (err != 0) {
+ err(udev, "chown(%s, %u, %u) failed: %m\n", file, uid, gid);
+ goto exit;
+ }
+ }
+
info(udev, "chmod(%s, %#o)\n", file, mode);
err = chmod(file, mode);
if (err != 0) {
@@ -120,15 +136,6 @@ int udev_node_mknod(struct udev_device *dev, const char *file, dev_t devnum, mod
goto exit;
}
}
-
- if (!preserve || stats.st_uid != uid || stats.st_gid != gid) {
- info(udev, "chown(%s, %u, %u)\n", file, uid, gid);
- err = chown(file, uid, gid);
- if (err != 0) {
- err(udev, "chown(%s, %u, %u) failed: %m\n", file, uid, gid);
- goto exit;
- }
- }
exit:
return err;
}
--
To unsubscribe from this list: send the line "unsubscribe linux-hotplug" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
