| Message ID | 1311602350-10857-1-git-send-email-piastryyy@gmail.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
makes sense. Doesn't it need to be added to stable. On Mon, Jul 25, 2011 at 8:59 AM, Pavel Shilovsky <piastryyy@gmail.com> wrote: > commit fec11dd9a0109fe52fd631e5c510778d6cbff6cc caused > a regression when we have already mounted //server/share/a > and want to mount //server/share/a/b. > > The problem is that lookup_one_len calls __lookup_hash > with nd pointer as NULL. Then __lookup_hash calls > do_revalidate in the case when dentry exists and we end > up with NULL pointer deference in cifs_d_revalidate: > > if (nd->flags & LOOKUP_RCU) > return -ECHILD; > > Fix this by checking nd for NULL. > > Signed-off-by: Pavel Shilovsky <piastryyy@gmail.com> > --- > fs/cifs/dir.c | 2 +- > 1 files changed, 1 insertions(+), 1 deletions(-) > > diff --git a/fs/cifs/dir.c b/fs/cifs/dir.c > index fa8c21d..d8d26f3 100644 > --- a/fs/cifs/dir.c > +++ b/fs/cifs/dir.c > @@ -641,7 +641,7 @@ lookup_out: > static int > cifs_d_revalidate(struct dentry *direntry, struct nameidata *nd) > { > - if (nd->flags & LOOKUP_RCU) > + if (nd && (nd->flags & LOOKUP_RCU)) > return -ECHILD; > > if (direntry->d_inode) { > -- > 1.7.1 > >
diff --git a/fs/cifs/dir.c b/fs/cifs/dir.c index fa8c21d..d8d26f3 100644 --- a/fs/cifs/dir.c +++ b/fs/cifs/dir.c @@ -641,7 +641,7 @@ lookup_out: static int cifs_d_revalidate(struct dentry *direntry, struct nameidata *nd) { - if (nd->flags & LOOKUP_RCU) + if (nd && (nd->flags & LOOKUP_RCU)) return -ECHILD; if (direntry->d_inode) {
commit fec11dd9a0109fe52fd631e5c510778d6cbff6cc caused a regression when we have already mounted //server/share/a and want to mount //server/share/a/b. The problem is that lookup_one_len calls __lookup_hash with nd pointer as NULL. Then __lookup_hash calls do_revalidate in the case when dentry exists and we end up with NULL pointer deference in cifs_d_revalidate: if (nd->flags & LOOKUP_RCU) return -ECHILD; Fix this by checking nd for NULL. Signed-off-by: Pavel Shilovsky <piastryyy@gmail.com> --- fs/cifs/dir.c | 2 +- 1 files changed, 1 insertions(+), 1 deletions(-)