crypto: ccp - Check for NULL PSP pointer at module unload

Should the PSP initialization fail, the PSP data structure will be freed and the value contained in the sp_device struct set to NULL. At module unload, psp_dev_destroy() does not check if the pointer value is NULL and will end up dereferencing a NULL pointer. Add a pointer check of the psp_data field in the sp_device struct in psp_dev_destroy() and return immediately if it is NULL. Cc: <[email protected]> # 4.16.x- Fixes: 2a6170d ("crypto: ccp: Add Platform Security Processor (PSP) device support") Signed-off-by: Tom Lendacky <[email protected]> Acked-by: Gary R Hook <[email protected]> Signed-off-by: Herbert Xu <[email protected]>
josf · Aug 3, 2018 · afb31cd · afb31cd
1 parent 4e34e51
commit afb31cd
Showing 1 changed file with 3 additions and 0 deletions.
diff --git a/drivers/crypto/ccp/psp-dev.c b/drivers/crypto/ccp/psp-dev.c
@@ -858,6 +858,9 @@ void psp_dev_destroy(struct sp_device *sp)
 {
 	struct psp_device *psp = sp->psp_data;
 
+	if (!psp)
+		return;
+
 	if (psp->sev_misc)
 		kref_put(&misc_dev->refcount, sev_exit);