pstore: Fix NULL pointer fault if get NULL prz in ramoops_get_next_prz
ramoops_get_next_prz get the prz according the paramters. If it get a
uninitialized prz, access its members by following persistent_ram_old_size(prz)
will cause a NULL pointer crash.
Ex: if ftrace_size is 0, fprz will be NULL.
Fix it by return NULL in advance.
Signed-off-by: Liu ShuoX <shuox.liu@intel.com>
Acked-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Tony Luck <tony.luck@intel.com>
diff --git a/fs/pstore/ram.c b/fs/pstore/ram.c
index 1daed280..6f96d8c 100644
--- a/fs/pstore/ram.c
+++ b/fs/pstore/ram.c
@@ -119,6 +119,8 @@
return NULL;
prz = przs[i];
+ if (!prz)
+ return NULL;
/* Update old/shadowed buffer. */
if (update)