Hi Peter,
Thanks for pointing out the typo. In the kernel, struct ext3_dir_entry_2 has a 8-bit name_len field followed by 8-bit field for filetype. Whereas in e2fsck, struct ext2_dir_entry has a 16-bit name_len field, the upper 8 bits of which store the filetype. Hence e2fsck masks the upper 8 bits while using name_len.
Here is the patch with the change.
Signed-off-by: Andreas Dilger <adilger@xxxxxxxxxxxxx>
Signed-off-by: Kalpak Shah <kalpak@xxxxxxxxxxxxx>
Index: e2fsprogs-1.39/e2fsck/pass2.c
===================================================================
--- e2fsprogs-1.39.orig/e2fsck/pass2.c
+++ e2fsprogs-1.39/e2fsck/pass2.c
@@ -495,7 +495,9 @@ static _INLINE_ int check_filetype(e2fsc
return 1;
}
- if (ext2fs_test_inode_bitmap(ctx->inode_dir_map, dirent->inode)) {
+ if (ext2fs_test_inode_bitmap(ctx->inode_dir_map, dirent->inode) ||
+ ((dirent->name_len & 0xFF) <= 2 && dirent->name[0] == '.' &&
+ (dirent->name[1] == '.' || dirent->name[1] == '\0'))) {
should_be = EXT2_FT_DIR;
} else if (ext2fs_test_inode_bitmap(ctx->inode_reg_map,
dirent->inode)) {
Thanks,
Kalpak Shah. <kalpak@xxxxxxxxxxxxx>
On Wed, 2007-02-21 at 09:49 -0500, Peter Staubach wrote:
> Kalpak Shah wrote:
> > Hi,
> >
> > If the mode of a directory gets corrupted, check_filetype() makes wrong decisions for all its sub-directories. For example, using debugfs we can corrupt the mode of a directory to 0140755 (i.e. a socket). e2fsck will set the filetype of all its subdirectories as 6 (filetype for socket). All the subdirectories would be moved to lost+found, and in second run of e2fsck their filetype would be set back to 2.
> >
> > By the time we come to check_filetype(), we have already verified the "." and ".." entries, so we special case these dirents in check_filetype().
> >
> > Please consider for review.
> >
> > Signed-off-by: Andreas Dilger <adilger@xxxxxxxxxxxxx>
> > Signed-off-by: Kalpak Shah <kalpak@xxxxxxxxxxxxx>
> >
> >
> > Index: e2fsprogs-1.39/e2fsck/pass2.c
> > ===================================================================
> > --- e2fsprogs-1.39.orig/e2fsck/pass2.c
> > +++ e2fsprogs-1.39/e2fsck/pass2.c
> > @@ -495,7 +495,9 @@ static _INLINE_ int check_filetype(e2fsc
> > return 1;
> > }
> >
> > - if (ext2fs_test_inode_bitmap(ctx->inode_dir_map, dirent->inode)) {
> > + if (ext2fs_test_inode_bitmap(ctx->inode_dir_map, dirent->inode) ||
> > + ((dirent->name_len && 0xFF) <= 2 && dirent->name[0] == '.' &&
> >
>
> What is the "&& 0xFF" part for? At the very least, it should probably
> be "& 0xFF". It doesn't seem like this mask should be needed at all
> though, I think.
>
> Thanx...
>
> ps
>
> > + (dirent->name[1] == '.' || dirent->name[1] == '\0'))) {
> > should_be = EXT2_FT_DIR;
> > } else if (ext2fs_test_inode_bitmap(ctx->inode_reg_map,
> > dirent->inode)) {
> >
> >
> > -
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> >
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