a) don't bother with ->d_time for positives - we only check it for negatives
anyway.
b) make sure to set it at unlink and rmdir time - at *that* point soon-to-be
negative dentry matches then-current directory contents
c) don't go into renaming of old alias in vfat_lookup() unless it has
the same parent (which it will, unless we are seeing corrupted image)
Signed-off-by: Al Viro <[email protected]>
Cc: <[email protected]> # 3.17.x
[Make change minimum, don't call d_move() for dir]
Signed-off-by: OGAWA Hirofumi <[email protected]>
---
fs/fat/namei_vfat.c | 20 +++++++++++---------
1 file changed, 11 insertions(+), 9 deletions(-)
diff -puN fs/fat/namei_vfat.c~fat-corrupt-fs-fix fs/fat/namei_vfat.c
--- linux/fs/fat/namei_vfat.c~fat-corrupt-fs-fix 2014-11-10 01:09:08.782815944 +0900
+++ linux-hirofumi/fs/fat/namei_vfat.c 2014-11-10 01:56:47.283117983 +0900
@@ -736,7 +736,12 @@ static struct dentry *vfat_lookup(struct
}
alias = d_find_alias(inode);
- if (alias && !vfat_d_anon_disconn(alias)) {
+ /*
+ * Checking "alias->d_parent == dentry->d_parent" to make sure
+ * FS is not corrupted (especially double linked dir).
+ */
+ if (alias && alias->d_parent == dentry->d_parent &&
+ !vfat_d_anon_disconn(alias)) {
/*
* This inode has non anonymous-DCACHE_DISCONNECTED
* dentry. This means, the user did ->lookup() by an
@@ -755,12 +760,9 @@ static struct dentry *vfat_lookup(struct
out:
mutex_unlock(&MSDOS_SB(sb)->s_lock);
- dentry->d_time = dentry->d_parent->d_inode->i_version;
- dentry = d_splice_alias(inode, dentry);
- if (dentry)
- dentry->d_time = dentry->d_parent->d_inode->i_version;
- return dentry;
-
+ if (!inode)
+ dentry->d_time = dir->i_version;
+ return d_splice_alias(inode, dentry);
error:
mutex_unlock(&MSDOS_SB(sb)->s_lock);
return ERR_PTR(err);
@@ -793,7 +795,6 @@ static int vfat_create(struct inode *dir
inode->i_mtime = inode->i_atime = inode->i_ctime = ts;
/* timestamp is already written, so mark_inode_dirty() is unneeded. */
- dentry->d_time = dentry->d_parent->d_inode->i_version;
d_instantiate(dentry, inode);
out:
mutex_unlock(&MSDOS_SB(sb)->s_lock);
@@ -824,6 +825,7 @@ static int vfat_rmdir(struct inode *dir,
clear_nlink(inode);
inode->i_mtime = inode->i_atime = CURRENT_TIME_SEC;
fat_detach(inode);
+ dentry->d_time = dir->i_version;
out:
mutex_unlock(&MSDOS_SB(sb)->s_lock);
@@ -849,6 +851,7 @@ static int vfat_unlink(struct inode *dir
clear_nlink(inode);
inode->i_mtime = inode->i_atime = CURRENT_TIME_SEC;
fat_detach(inode);
+ dentry->d_time = dir->i_version;
out:
mutex_unlock(&MSDOS_SB(sb)->s_lock);
@@ -889,7 +892,6 @@ static int vfat_mkdir(struct inode *dir,
inode->i_mtime = inode->i_atime = inode->i_ctime = ts;
/* timestamp is already written, so mark_inode_dirty() is unneeded. */
- dentry->d_time = dentry->d_parent->d_inode->i_version;
d_instantiate(dentry, inode);
mutex_unlock(&MSDOS_SB(sb)->s_lock);
_
On Thu, 27 Nov 2014 00:31:28 +0900 OGAWA Hirofumi <[email protected]> wrote:
> a) don't bother with ->d_time for positives - we only check it for negatives
> anyway.
> b) make sure to set it at unlink and rmdir time - at *that* point soon-to-be
> negative dentry matches then-current directory contents
> c) don't go into renaming of old alias in vfat_lookup() unless it has
> the same parent (which it will, unless we are seeing corrupted image)
>
> Signed-off-by: Al Viro <[email protected]>
> Cc: <[email protected]> # 3.17.x
> [Make change minimum, don't call d_move() for dir]
> Signed-off-by: OGAWA Hirofumi <[email protected]>
It's unclear who did the "[Make change minimum.." alteration.
I do it this way:
[[email protected]: make change minimum, don't call d_move() for dir]
Also, who was the primary author of this patch? It *looks* like it was
Al, unsure. If it was indeed Al then this can be communicated by
putting his From: line at the very top of the changelog body.
Andrew Morton <[email protected]> writes:
> On Thu, 27 Nov 2014 00:31:28 +0900 OGAWA Hirofumi <[email protected]> wrote:
>
>> a) don't bother with ->d_time for positives - we only check it for negatives
>> anyway.
>> b) make sure to set it at unlink and rmdir time - at *that* point soon-to-be
>> negative dentry matches then-current directory contents
>> c) don't go into renaming of old alias in vfat_lookup() unless it has
>> the same parent (which it will, unless we are seeing corrupted image)
>>
>> Signed-off-by: Al Viro <[email protected]>
>> Cc: <[email protected]> # 3.17.x
>> [Make change minimum, don't call d_move() for dir]
>> Signed-off-by: OGAWA Hirofumi <[email protected]>
>
> It's unclear who did the "[Make change minimum.." alteration.
>
> I do it this way:
> [[email protected]: make change minimum, don't call d_move() for dir]
I see. OK, I will also use your format next time.
> Also, who was the primary author of this patch? It *looks* like it was
> Al, unsure. If it was indeed Al then this can be communicated by
> putting his From: line at the very top of the changelog body.
Ah, sorry. The patch is written by Al, and I was forgetting to add "From:".
--
OGAWA Hirofumi <[email protected]>