ramoops: add pdata NULL check to ramoops_probe
This adds a check for a NULL platform data, which should only be possible
if a driver incorrectly sets up a probe request without also having defined
the platform_data structure. This is based on a patch from Geliang Tang.
Signed-off-by: Kees Cook <keescook@chromium.org>
diff --git a/fs/pstore/ram.c b/fs/pstore/ram.c
index 3802224..27c059e 100644
--- a/fs/pstore/ram.c
+++ b/fs/pstore/ram.c
@@ -734,11 +734,20 @@
goto fail_out;
}
- /* Only a single ramoops area allowed at a time, so fail extra
+ /*
+ * Only a single ramoops area allowed at a time, so fail extra
* probes.
*/
- if (cxt->max_dump_cnt)
+ if (cxt->max_dump_cnt) {
+ pr_err("already initialized\n");
goto fail_out;
+ }
+
+ /* Make sure we didn't get bogus platform data pointer. */
+ if (!pdata) {
+ pr_err("NULL platform data\n");
+ goto fail_out;
+ }
if (!pdata->mem_size || (!pdata->record_size && !pdata->console_size &&
!pdata->ftrace_size && !pdata->pmsg_size)) {