* [bug report] ovl: copy up of disconnected dentries
@ 2021-03-22 12:18 Dan Carpenter
2021-03-22 12:25 ` Amir Goldstein
0 siblings, 1 reply; 3+ messages in thread
From: Dan Carpenter @ 2021-03-22 12:18 UTC (permalink / raw)
To: amir73il; +Cc: linux-unionfs
Hello Amir Goldstein,
The patch aa3ff3c152ff: "ovl: copy up of disconnected dentries" from
Oct 15, 2017, leads to the following static checker warning:
fs/overlayfs/copy_up.c:972 ovl_copy_up_flags()
warn: 'old_cred' not released on lines: 944.
fs/overlayfs/copy_up.c
932 static int ovl_copy_up_flags(struct dentry *dentry, int flags)
933 {
934 int err = 0;
935 const struct cred *old_cred = ovl_override_creds(dentry->d_sb);
936 bool disconnected = (dentry->d_flags & DCACHE_DISCONNECTED);
937
938 /*
939 * With NFS export, copy up can get called for a disconnected non-dir.
940 * In this case, we will copy up lower inode to index dir without
941 * linking it to upper dir.
942 */
943 if (WARN_ON(disconnected && d_is_dir(dentry)))
944 return -EIO;
Should this call revert_creds(old_cred); before returning?
945
946 while (!err) {
947 struct dentry *next;
948 struct dentry *parent = NULL;
949
950 if (ovl_already_copied_up(dentry, flags))
951 break;
952
953 next = dget(dentry);
954 /* find the topmost dentry not yet copied up */
955 for (; !disconnected;) {
956 parent = dget_parent(next);
957
958 if (ovl_dentry_upper(parent))
959 break;
960
961 dput(next);
962 next = parent;
963 }
964
965 err = ovl_copy_up_one(parent, next, flags);
966
967 dput(parent);
968 dput(next);
969 }
970 revert_creds(old_cred);
971
972 return err;
973 }
regards,
dan carpenter
^ permalink raw reply [flat|nested] 3+ messages in thread* Re: [bug report] ovl: copy up of disconnected dentries
2021-03-22 12:18 [bug report] ovl: copy up of disconnected dentries Dan Carpenter
@ 2021-03-22 12:25 ` Amir Goldstein
2021-03-22 12:35 ` Dan Carpenter
0 siblings, 1 reply; 3+ messages in thread
From: Amir Goldstein @ 2021-03-22 12:25 UTC (permalink / raw)
To: Dan Carpenter; +Cc: overlayfs
On Mon, Mar 22, 2021 at 2:18 PM Dan Carpenter <dan.carpenter@oracle.com> wrote:
>
> Hello Amir Goldstein,
>
> The patch aa3ff3c152ff: "ovl: copy up of disconnected dentries" from
> Oct 15, 2017, leads to the following static checker warning:
Heh! that's fashionably late :)
>
> fs/overlayfs/copy_up.c:972 ovl_copy_up_flags()
> warn: 'old_cred' not released on lines: 944.
>
> fs/overlayfs/copy_up.c
> 932 static int ovl_copy_up_flags(struct dentry *dentry, int flags)
> 933 {
> 934 int err = 0;
> 935 const struct cred *old_cred = ovl_override_creds(dentry->d_sb);
> 936 bool disconnected = (dentry->d_flags & DCACHE_DISCONNECTED);
> 937
> 938 /*
> 939 * With NFS export, copy up can get called for a disconnected non-dir.
> 940 * In this case, we will copy up lower inode to index dir without
> 941 * linking it to upper dir.
> 942 */
> 943 if (WARN_ON(disconnected && d_is_dir(dentry)))
> 944 return -EIO;
>
> Should this call revert_creds(old_cred); before returning?
Yes. Here's a simple fix, care to post it?
Thanks,
Amir.
diff --git a/fs/overlayfs/copy_up.c b/fs/overlayfs/copy_up.c
index 0b2891c6c71e..2846b943e80c 100644
--- a/fs/overlayfs/copy_up.c
+++ b/fs/overlayfs/copy_up.c
@@ -932,7 +932,7 @@ static int ovl_copy_up_one(struct dentry *parent,
struct dentry *dentry,
static int ovl_copy_up_flags(struct dentry *dentry, int flags)
{
int err = 0;
- const struct cred *old_cred = ovl_override_creds(dentry->d_sb);
+ const struct cred *old_cred;
bool disconnected = (dentry->d_flags & DCACHE_DISCONNECTED);
/*
@@ -943,6 +943,7 @@ static int ovl_copy_up_flags(struct dentry
*dentry, int flags)
if (WARN_ON(disconnected && d_is_dir(dentry)))
return -EIO;
+ old_cred = ovl_override_creds(dentry->d_sb);
while (!err) {
struct dentry *next;
struct dentry *parent = NULL;
^ permalink raw reply related [flat|nested] 3+ messages in thread* Re: [bug report] ovl: copy up of disconnected dentries
2021-03-22 12:25 ` Amir Goldstein
@ 2021-03-22 12:35 ` Dan Carpenter
0 siblings, 0 replies; 3+ messages in thread
From: Dan Carpenter @ 2021-03-22 12:35 UTC (permalink / raw)
To: Amir Goldstein; +Cc: overlayfs
On Mon, Mar 22, 2021 at 02:25:44PM +0200, Amir Goldstein wrote:
> On Mon, Mar 22, 2021 at 2:18 PM Dan Carpenter <dan.carpenter@oracle.com> wrote:
> >
> > Hello Amir Goldstein,
> >
> > The patch aa3ff3c152ff: "ovl: copy up of disconnected dentries" from
> > Oct 15, 2017, leads to the following static checker warning:
>
> Heh! that's fashionably late :)
>
;)
> >
> > fs/overlayfs/copy_up.c:972 ovl_copy_up_flags()
> > warn: 'old_cred' not released on lines: 944.
> >
> > fs/overlayfs/copy_up.c
> > 932 static int ovl_copy_up_flags(struct dentry *dentry, int flags)
> > 933 {
> > 934 int err = 0;
> > 935 const struct cred *old_cred = ovl_override_creds(dentry->d_sb);
> > 936 bool disconnected = (dentry->d_flags & DCACHE_DISCONNECTED);
> > 937
> > 938 /*
> > 939 * With NFS export, copy up can get called for a disconnected non-dir.
> > 940 * In this case, we will copy up lower inode to index dir without
> > 941 * linking it to upper dir.
> > 942 */
> > 943 if (WARN_ON(disconnected && d_is_dir(dentry)))
> > 944 return -EIO;
> >
> > Should this call revert_creds(old_cred); before returning?
>
> Yes. Here's a simple fix, care to post it?
Sure. I'm always happy to take credit for your work. I'll send it
tomorrow.
regards,
dan carpenter
^ permalink raw reply [flat|nested] 3+ messages in thread
end of thread, other threads:[~2021-03-22 12:38 UTC | newest]
Thread overview: 3+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2021-03-22 12:18 [bug report] ovl: copy up of disconnected dentries Dan Carpenter
2021-03-22 12:25 ` Amir Goldstein
2021-03-22 12:35 ` Dan Carpenter
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).