udf: Check path length when reading symlink

Symlink reading code does not check whether the resulting path fits into
the page provided by the generic code. This isn't as easy as just
checking the symlink size because of various encoding conversions we
perform on path. So we have to check whether there is still enough space
in the buffer on the fly.

CC: stable@vger.kernel.org
Reported-by: Carl Henrik Lunde <chlunde@ping.uio.no>
Signed-off-by: Jan Kara <jack@suse.cz>

1 files changed, 2 insertions, 1 deletions

diff --git a/fs/udf/udfdecl.h b/fs/udf/udfdecl.h
index 1cc3c993ebd0..47bb3f5ca360 100644
--- a/fs/udf/udfdecl.h
+++ b/fs/udf/udfdecl.h
@@ -211,7 +211,8 @@ udf_get_lb_pblock(struct super_block *sb, struct kernel_lb_addr *loc,
 }
 
 /* unicode.c */
-extern int udf_get_filename(struct super_block *, uint8_t *, uint8_t *, int);
+extern int udf_get_filename(struct super_block *, uint8_t *, int, uint8_t *,
+                            int);
 extern int udf_put_filename(struct super_block *, const uint8_t *, uint8_t *,
                             int);
 extern int udf_build_ustr(struct ustr *, dstring *, int);