commit
a1d47b262952a45aae62bd49cfaf33dd76c11a2c upstream.
UDF specification allows arbitrarily large symlinks. However we support
only symlinks at most one block large. Check the length of the symlink
so that we don't access memory beyond end of the symlink block.
Reported-by: Carl Henrik Lunde <chlunde@gmail.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
struct inode *inode = page->mapping->host;
struct buffer_head *bh = NULL;
unsigned char *symlink;
struct inode *inode = page->mapping->host;
struct buffer_head *bh = NULL;
unsigned char *symlink;
unsigned char *p = kmap(page);
struct udf_inode_info *iinfo;
uint32_t pos;
unsigned char *p = kmap(page);
struct udf_inode_info *iinfo;
uint32_t pos;
+ /* We don't support symlinks longer than one block */
+ if (inode->i_size > inode->i_sb->s_blocksize) {
+ err = -ENAMETOOLONG;
+ goto out_unmap;
+ }
+
iinfo = UDF_I(inode);
pos = udf_block_map(inode, 0);
iinfo = UDF_I(inode);
pos = udf_block_map(inode, 0);
} else {
bh = sb_bread(inode->i_sb, pos);
} else {
bh = sb_bread(inode->i_sb, pos);
+ if (!bh) {
+ err = -EIO;
+ goto out_unlock_inode;
+ }
unlock_page(page);
return 0;
unlock_page(page);
return 0;
up_read(&iinfo->i_data_sem);
SetPageError(page);
up_read(&iinfo->i_data_sem);
SetPageError(page);
kunmap(page);
unlock_page(page);
return err;
kunmap(page);
unlock_page(page);
return err;