[PATCH 1/1] ext4: detect directories in ext4fs_exists()

[Heinrich Schuchardt]

While fat_exists() reports directories and files as existing
ext4fs_exists() only recognizes files. This lead to errors
when using systemd-boot with an ext4 file-system.

Change ext4fs_exists() to find any type of inode:
files, directories, symbolic links.

Fixes: a1596438a689 ("ext4fs ls load support")
Signed-off-by: Heinrich Schuchardt <heinrich.schuchardt at canonical.com>
---
I still need to figure out a good test. Currently 'xxd' is the only command
invoking fs_exists().
---
 fs/ext4/ext4_common.c |  5 ++---
 fs/ext4/ext4_common.h |  2 ++
 fs/ext4/ext4fs.c      | 11 +++++++----
 3 files changed, 11 insertions(+), 7 deletions(-)

diff --git a/fs/ext4/ext4_common.c b/fs/ext4/ext4_common.c
index ea9b92298ba..365c5147c4b 100644
--- a/fs/ext4/ext4_common.c
+++ b/fs/ext4/ext4_common.c
@@ -2214,9 +2214,8 @@ static char *ext4fs_read_symlink(struct ext2fs_node *node)
 	return symlink;
 }
 
-static int ext4fs_find_file1(const char *currpath,
-			     struct ext2fs_node *currroot,
-			     struct ext2fs_node **currfound, int *foundtype)
+int ext4fs_find_file1(const char *currpath, struct ext2fs_node *currroot,
+		      struct ext2fs_node **currfound, int *foundtype)
 {
 	char fpath[strlen(currpath) + 1];
 	char *name = fpath;
diff --git a/fs/ext4/ext4_common.h b/fs/ext4/ext4_common.h
index 504c708b064..84500e990aa 100644
--- a/fs/ext4/ext4_common.h
+++ b/fs/ext4/ext4_common.h
@@ -54,6 +54,8 @@ int ext4fs_read_file(struct ext2fs_node *node, loff_t pos, loff_t len,
 		     char *buf, loff_t *actread);
 int ext4fs_find_file(const char *path, struct ext2fs_node *rootnode,
 			struct ext2fs_node **foundnode, int expecttype);
+int ext4fs_find_file1(const char *currpath, struct ext2fs_node *currroot,
+		      struct ext2fs_node **currfound, int *foundtype);
 int ext4fs_iterate_dir(struct ext2fs_node *dir, char *name,
 			struct ext2fs_node **fnode, int *ftype);
 
diff --git a/fs/ext4/ext4fs.c b/fs/ext4/ext4fs.c
index 3b12ec54fa2..b1359d14909 100644
--- a/fs/ext4/ext4fs.c
+++ b/fs/ext4/ext4fs.c
@@ -208,11 +208,14 @@ int ext4fs_ls(const char *dirname)
 
 int ext4fs_exists(const char *filename)
 {
-	loff_t file_len;
-	int ret;
+	struct ext2fs_node *dirnode = NULL;
+	int filetype;
 
-	ret = ext4fs_open(filename, &file_len);
-	return ret == 0;
+	if (!filename)
+		return 0;
+
+	return ext4fs_find_file1(filename, &ext4fs_root->diropen, &dirnode,
+				 &filetype);
 }
 
 int ext4fs_size(const char *filename, loff_t *size)
-- 
2.43.0