Merge tag 'v4.4.33' into dev-4.4openbmc-4.4-20161121-1dev-4.4

This is the 4.4.33 stable release

Signed-off-by: Joel Stanley <joel@jms.id.au>

1 files changed, 55 insertions, 4 deletions

diff --git a/fs/fuse/dir.c b/fs/fuse/dir.c
index 5e2e08712d3b..4b5f2c4e69c8 100644
--- a/fs/fuse/dir.c
+++ b/fs/fuse/dir.c
@@ -1697,14 +1697,46 @@ error:
 static int fuse_setattr(struct dentry *entry, struct iattr *attr)
 {
 	struct inode *inode = d_inode(entry);
+	struct file *file = (attr->ia_valid & ATTR_FILE) ? attr->ia_file : NULL;
+	int ret;
 
 	if (!fuse_allow_current_process(get_fuse_conn(inode)))
 		return -EACCES;
 
-	if (attr->ia_valid & ATTR_FILE)
-		return fuse_do_setattr(inode, attr, attr->ia_file);
-	else
-		return fuse_do_setattr(inode, attr, NULL);
+	if (attr->ia_valid & (ATTR_KILL_SUID | ATTR_KILL_SGID)) {
+		int kill;
+
+		attr->ia_valid &= ~(ATTR_KILL_SUID | ATTR_KILL_SGID |
+				    ATTR_MODE);
+		/*
+		 * ia_mode calculation may have used stale i_mode.  Refresh and
+		 * recalculate.
+		 */
+		ret = fuse_do_getattr(inode, NULL, file);
+		if (ret)
+			return ret;
+
+		attr->ia_mode = inode->i_mode;
+		kill = should_remove_suid(entry);
+		if (kill & ATTR_KILL_SUID) {
+			attr->ia_valid |= ATTR_MODE;
+			attr->ia_mode &= ~S_ISUID;
+		}
+		if (kill & ATTR_KILL_SGID) {
+			attr->ia_valid |= ATTR_MODE;
+			attr->ia_mode &= ~S_ISGID;
+		}
+	}
+	if (!attr->ia_valid)
+		return 0;
+
+	ret = fuse_do_setattr(inode, attr, file);
+	if (!ret) {
+		/* Directory mode changed, may need to revalidate access */
+		if (d_is_dir(entry) && (attr->ia_valid & ATTR_MODE))
+			fuse_invalidate_entry_cache(entry);
+	}
+	return ret;
 }
 
 static int fuse_getattr(struct vfsmount *mnt, struct dentry *entry,
@@ -1797,6 +1829,23 @@ static ssize_t fuse_getxattr(struct dentry *entry, const char *name,
 	return ret;
 }
 
+static int fuse_verify_xattr_list(char *list, size_t size)
+{
+	size_t origsize = size;
+
+	while (size) {
+		size_t thislen = strnlen(list, size);
+
+		if (!thislen || thislen == size)
+			return -EIO;
+
+		size -= thislen + 1;
+		list += thislen + 1;
+	}
+
+	return origsize;
+}
+
 static ssize_t fuse_listxattr(struct dentry *entry, char *list, size_t size)
 {
 	struct inode *inode = d_inode(entry);
@@ -1832,6 +1881,8 @@ static ssize_t fuse_listxattr(struct dentry *entry, char *list, size_t size)
 	ret = fuse_simple_request(fc, &args);
 	if (!ret && !size)
 		ret = outarg.size;
+	if (ret > 0 && size)
+		ret = fuse_verify_xattr_list(list, ret);
 	if (ret == -ENOSYS) {
 		fc->no_listxattr = 1;
 		ret = -EOPNOTSUPP;