Re: [RFC] FAT extension filters

[OGAWA Hirofumi]

"Albert D. Cahalan" <[e-mail]> writes:

> Using plain old MS-DOS, or Linux right before the
> vfat code was merged, create a file with this name:
> 
> E5 44 05 44 E5 44 44 44   44 E5 05
> 
> On disk it gets stored as this:
> 
> 05 44 05 44 E5 44 44 44   44 E5 05
> ^^
> 
> Now remount or reboot so you don't cheat by
> accident. Do an "ls -l" and note that you
> see the original filename. The 0xE5 is at
> the beginning of the name, and the 0x05 in
> the middle has not been mangled.

Ah, yes. Indeed.

I'll submit the following patch to Linus. Thanks.

diff -urN linux-bk/fs/fat/dir.c linux-2.5.14/fs/fat/dir.c
--- linux-bk/fs/fat/dir.c	Mon May 13 02:28:29 2002
+++ linux-2.5.14/fs/fat/dir.c	Thu May 16 22:39:32 2002
@@ -271,13 +271,10 @@
 				long_slots = 0;
 		}
 
-		for (i = 0; i < 8; i++) {
-			/* see namei.c, msdos_format_name */
-			if (de->name[i] == 0x05)
-				work[i] = 0xE5;
-			else
-				work[i] = de->name[i];
-		}
+		/* see namei.c, msdos_format_name */
+		memcpy(work, de->name, sizeof(de->name));
+		if (de->name[0] == 0x05)
+			work[0] = 0xE5;
 		for (i = 0, j = 0, last_u = 0; i < 8;) {
 			if (!work[i]) break;
 			chl = fat_shortname2uni(nls_disk, &work[i], 8 - i,
@@ -478,13 +475,10 @@
 		dotoffset = 1;
 	}
 
-	for (i = 0; i < 8; i++) {
-		/* see namei.c, msdos_format_name */
-		if (de->name[i] == 0x05)
-			work[i] = 0xE5;
-		else
-			work[i] = de->name[i];
-	}
+	/* see namei.c, msdos_format_name */
+	memcpy(work, de->name, sizeof(de->name));
+	if (de->name[0] == 0x05)
+		work[0] = 0xE5;
 	for (i = 0, j = 0, last = 0, last_u = 0; i < 8;) {
 		if (!(c = work[i])) break;
 		chl = fat_shortname2uni(nls_disk, &work[i], 8 - i,
-- 
OGAWA Hirofumi <[e-mail]>