affs: add mount option to avoid filename truncates

Normal behavior for filenames exceeding specific filesystem limits is to
refuse operation.

AFFS standard name length being only 30 characters against 255 for usual
Linux filesystems, original implementation does filename truncate by
default with a define value AFFS_NO_TRUNCATE which can be enabled but
needs module compilation.

This patch adds 'nofilenametruncate' mount option so that user can
easily activate that feature and avoid a lot of problems (eg overwrite
files ...)

Signed-off-by: Fabian Frederick <fabf@skynet.be>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 15 insertions, 8 deletions

diff --git a/fs/affs/amigaffs.c b/fs/affs/amigaffs.c
index d9a43674cb94..533a322c41c0 100644
--- a/fs/affs/amigaffs.c
+++ b/fs/affs/amigaffs.c
@@ -471,20 +471,27 @@ affs_warning(struct super_block *sb, const char *function, const char *fmt, ...)
 		function,ErrorBuffer);
 }
 
+bool
+affs_nofilenametruncate(const struct dentry *dentry)
+{
+	struct inode *inode = dentry->d_inode;
+	return AFFS_SB(inode->i_sb)->s_flags & SF_NO_TRUNCATE;
+
+}
+
 /* Check if the name is valid for a affs object. */
 
 int
-affs_check_name(const unsigned char *name, int len)
+affs_check_name(const unsigned char *name, int len, bool notruncate)
 {
 	int	 i;
 
-	if (len > 30)
-#ifdef AFFS_NO_TRUNCATE
-		return -ENAMETOOLONG;
-#else
-		len = 30;
-#endif
-
+	if (len > 30) {
+		if (notruncate)
+			return -ENAMETOOLONG;
+		else
+			len = 30;
+	}
 	for (i = 0; i < len; i++) {
 		if (name[i] < ' ' || name[i] == ':'
 		    || (name[i] > 0x7e && name[i] < 0xa0))