[2.6.20.21 review 26/35] dir_index: error out instead of BUG on corrupt dx dirs

Willy Tarreau
2007-10-13T14:50:59Z

[-- Attachment #1: 0082-dir_index-error-out-instead-of-BUG-on-corrupt-dx-di.patch --]
[-- Type: text/plain, Size: 4364 bytes --]

commit 3d82abae9523c33d4a16fdfdfd2bdde316d7b56a in mainline.

Convert asserts (BUGs) in dx_probe from bad on-disk data to recoverable
errors with helpful warnings. With help catching other asserts from Duane
Griffin <duaneg@dghda.com>

Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Acked-by: Duane Griffin <duaneg@dghda.com>
Acked-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
---
fs/ext3/namei.c | 34 ++++++++++++++++++++++++++++++----
fs/ext4/namei.c | 34 ++++++++++++++++++++++++++++++----
2 files changed, 60 insertions(+), 8 deletions(-)

Index: 2.6/fs/ext3/namei.c
===================================================================
--- 2.6.orig/fs/ext3/namei.c
+++ 2.6/fs/ext3/namei.c
@@ -380,13 +380,28 @@ dx_probe(struct dentry *dentry, struct i

entries = (struct dx_entry *) (((char *)&root->info) +
root->info.info_length);
- assert(dx_get_limit(entries) == dx_root_limit(dir,
- root->info.info_length));
+
+ if (dx_get_limit(entries) != dx_root_limit(dir,
+ root->info.info_length)) {
+ ext3_warning(dir->i_sb, __FUNCTION__,
+ "dx entry: limit != root limit");
+ brelse(bh);
+ *err = ERR_BAD_DX_DIR;
+ goto fail;
+ }
+
dxtrace (printk("Look up %x", hash));
while (1)
{
count = dx_get_count(entries);
- assert (count && count <= dx_get_limit(entries));
+ if (!count || count > dx_get_limit(entries)) {
+ ext3_warning(dir->i_sb, __FUNCTION__,
+ "dx entry: no count or count > limit");
+ brelse(bh);
+ *err = ERR_BAD_DX_DIR;
+ goto fail2;
+ }
+
p = entries + 1;
q = entries + count - 1;
while (p <= q)
@@ -424,8 +439,15 @@ dx_probe(struct dentry *dentry, struct i
if (!(bh = ext3_bread (NULL,dir, dx_get_block(at), 0, err)))
goto fail2;
at = entries = ((struct dx_node *) bh->b_data)->entries;
- assert (dx_get_limit(entries) == dx_node_limit (dir));
+ if (dx_get_limit(entries) != dx_node_limit (dir)) {
+ ext3_warning(dir->i_sb, __FUNCTION__,
+ "dx entry: limit != node limit");
+ brelse(bh);
+ *err = ERR_BAD_DX_DIR;
+ goto fail2;
+ }
frame++;
+ frame->bh = NULL;
}
fail2:
while (frame >= frame_in) {
@@ -433,6 +455,10 @@ fail2:
frame--;
}
fail:
+ if (*err == ERR_BAD_DX_DIR)
+ ext3_warning(dir->i_sb, __FUNCTION__,
+ "Corrupt dir inode %ld, running e2fsck is "
+ "recommended.", dir->i_ino);
return NULL;
}

Index: 2.6/fs/ext4/namei.c
===================================================================
--- 2.6.orig/fs/ext4/namei.c
+++ 2.6/fs/ext4/namei.c
@@ -380,13 +380,28 @@ dx_probe(struct dentry *dentry, struct i

entries = (struct dx_entry *) (((char *)&root->info) +
root->info.info_length);
- assert(dx_get_limit(entries) == dx_root_limit(dir,
- root->info.info_length));
+
+ if (dx_get_limit(entries) != dx_root_limit(dir,
+ root->info.info_length)) {
+ ext4_warning(dir->i_sb, __FUNCTION__,
+ "dx entry: limit != root limit");
+ brelse(bh);
+ *err = ERR_BAD_DX_DIR;
+ goto fail;
+ }
+
dxtrace (printk("Look up %x", hash));
while (1)
{
count = dx_get_count(entries);
- assert (count && count <= dx_get_limit(entries));
+ if (!count || count > dx_get_limit(entries)) {
+ ext4_warning(dir->i_sb, __FUNCTION__,
+ "dx entry: no count or count > limit");
+ brelse(bh);
+ *err = ERR_BAD_DX_DIR;
+ goto fail2;
+ }
+
p = entries + 1;
q = entries + count - 1;
while (p <= q)
@@ -424,8 +439,15 @@ dx_probe(struct dentry *dentry, struct i
if (!(bh = ext4_bread (NULL,dir, dx_get_block(at), 0, err)))
goto fail2;
at = entries = ((struct dx_node *) bh->b_data)->entries;
- assert (dx_get_limit(entries) == dx_node_limit (dir));
+ if (dx_get_limit(entries) != dx_node_limit (dir)) {
+ ext4_warning(dir->i_sb, __FUNCTION__,
+ "dx entry: limit != node limit");
+ brelse(bh);
+ *err = ERR_BAD_DX_DIR;
+ goto fail2;
+ }
frame++;
+ frame->bh = NULL;
}
fail2:
while (frame >= frame_in) {
@@ -433,6 +455,10 @@ fail2:
frame--;
}
fail:
+ if (*err == ERR_BAD_DX_DIR)
+ ext4_warning(dir->i_sb, __FUNCTION__,
+ "Corrupt dir inode %ld, running e2fsck is "
+ "recommended.", dir->i_ino);
return NULL;
}

--