pstore: skip zero size persistent ram buffer in traverse
In ramoops_pstore_read, a valid prz pointer with zero size buffer will
break traverse of all persistent ram buffers. The latter buffer might be
lost.
Signed-off-by: Liu ShuoX <shuox.liu@intel.com>
Cc: "Zhang, Yanmin" <yanmin_zhang@linux.intel.com>
Cc: Colin Cross <ccross@android.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Tony Luck <tony.luck@intel.com>
diff --git a/fs/pstore/ram.c b/fs/pstore/ram.c
index 9fe5b13..1daed280 100644
--- a/fs/pstore/ram.c
+++ b/fs/pstore/ram.c
@@ -120,12 +120,12 @@
prz = przs[i];
- if (update) {
- /* Update old/shadowed buffer. */
+ /* Update old/shadowed buffer. */
+ if (update)
persistent_ram_save_old(prz);
- if (!persistent_ram_old_size(prz))
- return NULL;
- }
+
+ if (!persistent_ram_old_size(prz))
+ return NULL;
*typep = type;
*id = i;