[UPDATE][PATCH 2/2] ext2: enlarge blocksize and fix rec_lenoverflow

  [2/2]  ext2: fix rec_len overflow
          - prevent rec_len from overflow with 64KB blocksize

Signed-off-by: Takashi Sato [email protected]
---
diff -Nupr -X linux-2.6.17-git13-Mingming/Documentation/dontdiff linux-2.6.17-git13-Mingming/fs/ext2/dir.c linux-2.6.17-git13-Mingming-reclen/fs/ext2/dir.c
--- linux-2.6.17-git13-Mingming/fs/ext2/dir.c	2006-07-07 17:24:11.000000000 +0900
+++ linux-2.6.17-git13-Mingming-reclen/fs/ext2/dir.c	2006-07-07 17:03:42.000000000 +0900
@@ -459,14 +459,23 @@ int ext2_add_link (struct dentry *dentry
 		kaddr = page_address(page);
 		dir_end = kaddr + ext2_last_byte(dir, n);
 		de = (ext2_dirent *)kaddr;
-		kaddr += PAGE_CACHE_SIZE - reclen;
+		if (chunk_size < EXT2_DIR_MAX_REC_LEN) 
+			kaddr += PAGE_CACHE_SIZE - reclen;
+		else 
+			kaddr += EXT2_DIR_MAX_REC_LEN - reclen;
 		while ((char *)de <= kaddr) {
 			if ((char *)de == dir_end) {
 				/* We hit i_size */
 				name_len = 0;
-				rec_len = chunk_size;
-				de->rec_len = cpu_to_le16(chunk_size);
 				de->inode = 0;
+				if (chunk_size  < EXT2_DIR_MAX_REC_LEN) {
+					rec_len = chunk_size;
+					de->rec_len = cpu_to_le16(chunk_size);
+				} else {
+					rec_len = EXT2_DIR_MAX_REC_LEN;
+					de->rec_len = 
+					cpu_to_le16(EXT2_DIR_MAX_REC_LEN);
+				}
 				goto got_it;
 			}
 			if (de->rec_len == 0) {
diff -Nupr -X linux-2.6.17-git13-Mingming/Documentation/dontdiff linux-2.6.17-git13-Mingming/include/linux/ext2_fs.h linux-2.6.17-git13-Mingming-reclen/include/linux/ext2_fs.h
--- linux-2.6.17-git13-Mingming/include/linux/ext2_fs.h	2006-07-07 17:24:12.000000000 +0900
+++ linux-2.6.17-git13-Mingming-reclen/include/linux/ext2_fs.h	2006-07-07 14:43:34.000000000 +0900
@@ -90,8 +90,8 @@ static inline struct ext2_sb_info *EXT2_
  * Macro-instructions used to manage several block sizes
  */
 #define EXT2_MIN_BLOCK_SIZE		1024
-#define	EXT2_MAX_BLOCK_SIZE		4096
-#define EXT2_MIN_BLOCK_LOG_SIZE		  10
+#define	EXT2_MAX_BLOCK_SIZE		65536
+#define EXT2_MIN_BLOCK_LOG_SIZE		10
 #ifdef __KERNEL__
 # define EXT2_BLOCK_SIZE(s)		((s)->s_blocksize)
 #else
@@ -553,5 +553,6 @@ enum {
 #define EXT2_DIR_ROUND 			(EXT2_DIR_PAD - 1)
 #define EXT2_DIR_REC_LEN(name_len)	(((name_len) + 8 + EXT2_DIR_ROUND) & \
 					 ~EXT2_DIR_ROUND)
+#define EXT2_DIR_MAX_REC_LEN		65532
 
 #endif	/* _LINUX_EXT2_FS_H */


Cheers sho