pstore: gracefully handle NULL pstore_info functions

If a pstore backend doesn't want to support various portions of the
pstore interface, it can just leave those functions NULL instead of
creating no-op stubs.

Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Tony Luck <tony.luck@intel.com>

1 files changed, 2 insertions, 1 deletions

diff --git a/fs/pstore/inode.c b/fs/pstore/inode.c
index 379a02dc1217..b3b426edb2fd 100644
--- a/fs/pstore/inode.c
+++ b/fs/pstore/inode.c
@@ -80,7 +80,8 @@ static int pstore_unlink(struct inode *dir, struct dentry *dentry)
 {
         struct pstore_private *p = dentry->d_inode->i_private;
 
-        p->psi->erase(p->type, p->id, p->psi);
+        if (p->psi->erase)
+                p->psi->erase(p->type, p->id, p->psi);
 
         return simple_unlink(dir, dentry);
 }