ext4: propagate error if creation of directory entry fails

In case the dir entry creation failed, ext4fs_write would later overwrite
a random inode, as inodeno was never initialized.

Signed-off-by: Stefan Brüns <stefan.bruens@rwth-aachen.de>
Reviewed-by: Lukasz Majewski <l.majewski@samsung.com>

diff --git a/fs/ext4/ext4_common.c b/fs/ext4/ext4_common.c
index d647ae0..680e001 100644 (file)
--- a/fs/ext4/ext4_common.c
+++ b/fs/ext4/ext4_common.c
@@ -366,7 +366,7 @@ static int check_void_in_dentry(struct ext2_dirent *dir, char *filename)
        return 0;
 }
 
-void ext4fs_update_parent_dentry(char *filename, int *p_ino, int file_type)
+int ext4fs_update_parent_dentry(char *filename, int file_type)
 {
        unsigned int *zero_buffer = NULL;
        char *root_first_block_buffer = NULL;
@@ -380,7 +380,7 @@ void ext4fs_update_parent_dentry(char *filename, int *p_ino, int file_type)
        unsigned int last_entry_dirlen;
        int sizeof_void_space = 0;
        int templength = 0;
-       int inodeno;
+       int inodeno = -1;
        int status;
        struct ext_filesystem *fs = get_fs();
        /* directory entry */
@@ -393,13 +393,13 @@ void ext4fs_update_parent_dentry(char *filename, int *p_ino, int file_type)
        zero_buffer = zalloc(fs->blksz);
        if (!zero_buffer) {
                printf("No Memory\n");
-               return;
+               return -1;
        }
        root_first_block_buffer = zalloc(fs->blksz);
        if (!root_first_block_buffer) {
                free(zero_buffer);
                printf("No Memory\n");
-               return;
+               return -1;
        }
 restart:
 
@@ -518,8 +518,6 @@ restart:
        temp_dir = temp_dir + sizeof(struct ext2_dirent);
        memcpy(temp_dir, filename, strlen(filename));
 
-       *p_ino = inodeno;
-
        /* update or write  the 1st block of root inode */
        if (ext4fs_put_metadata(root_first_block_buffer,
                                first_block_no_of_root))
@@ -528,6 +526,8 @@ restart:
 fail:
        free(zero_buffer);
        free(root_first_block_buffer);
+
+       return inodeno;
 }
 
 static int search_dir(struct ext2_inode *parent_inode, char *dirname)

diff --git a/fs/ext4/ext4_common.h b/fs/ext4/ext4_common.h
index 370a717..cc9d0c5 100644 (file)
--- a/fs/ext4/ext4_common.h
+++ b/fs/ext4/ext4_common.h
@@ -61,7 +61,7 @@ int ext4fs_iterate_dir(struct ext2fs_node *dir, char *name,
 uint32_t ext4fs_div_roundup(uint32_t size, uint32_t n);
 uint16_t ext4fs_checksum_update(unsigned int i);
 int ext4fs_get_parent_inode_num(const char *dirname, char *dname, int flags);
-void ext4fs_update_parent_dentry(char *filename, int *p_ino, int file_type);
+int ext4fs_update_parent_dentry(char *filename, int file_type);
 uint32_t ext4fs_get_new_blk_no(void);
 int ext4fs_get_new_inode_no(void);
 void ext4fs_reset_block_bmap(long int blockno, unsigned char *buffer,

diff --git a/fs/ext4/ext4_write.c b/fs/ext4/ext4_write.c
index 9200c47..a52804e 100644 (file)
--- a/fs/ext4/ext4_write.c
+++ b/fs/ext4/ext4_write.c
@@ -907,7 +907,9 @@ int ext4fs_write(const char *fname, unsigned char *buffer,
                goto fail;
        }
 
-       ext4fs_update_parent_dentry(filename, &inodeno, FILETYPE_REG);
+       inodeno = ext4fs_update_parent_dentry(filename, FILETYPE_REG);
+       if (inodeno == -1)
+               goto fail;
        /* prepare file inode */
        inode_buffer = zalloc(fs->inodesz);
        if (!inode_buffer)