hfsplus: add error checking for hfs_find_init()

hfs_find_init() may fail with ENOMEM, but there are places, where
the returned value is not checked. The consequences can be very
unpleasant, e.g. kfree uninitialized pointer and
inappropriate mutex unlocking.

The patch adds checks for errors in hfs_find_init().

Found by Linux Driver Verification project (linuxtesting.org).

Signed-off-by: Alexey Khoroshilov <khoroshilov@ispras.ru>
Signed-off-by: Christoph Hellwig <hch@lst.de>

1 files changed, 6 insertions, 2 deletions

diff --git a/fs/hfsplus/dir.c b/fs/hfsplus/dir.c
index 4df5059c25da..25b2443a004c 100644
--- a/fs/hfsplus/dir.c
+++ b/fs/hfsplus/dir.c
@@ -38,7 +38,9 @@ static struct dentry *hfsplus_lookup(struct inode *dir, struct dentry *dentry,
         sb = dir->i_sb;
 
         dentry->d_fsdata = NULL;
-        hfs_find_init(HFSPLUS_SB(sb)->cat_tree, &fd);
+        err = hfs_find_init(HFSPLUS_SB(sb)->cat_tree, &fd);
+        if (err)
+                return ERR_PTR(err);
         hfsplus_cat_build_key(sb, fd.search_key, dir->i_ino, &dentry->d_name);
 again:
         err = hfs_brec_read(&fd, &entry, sizeof(entry));
@@ -132,7 +134,9 @@ static int hfsplus_readdir(struct file *filp, void *dirent, filldir_t filldir)
         if (filp->f_pos >= inode->i_size)
                 return 0;
 
-        hfs_find_init(HFSPLUS_SB(sb)->cat_tree, &fd);
+        err = hfs_find_init(HFSPLUS_SB(sb)->cat_tree, &fd);
+        if (err)
+                return err;
         hfsplus_cat_build_key(sb, fd.search_key, inode->i_ino, NULL);
         err = hfs_brec_find(&fd);
         if (err)