[PATCH 4.13 036/110] crypto: drbg - fix freeing of resources

From: Greg Kroah-Hartman
Date: Tue Oct 03 2017 - 08:51:47 EST


4.13-stable review patch. If anyone has any objections, please let me know.

------------------

From: Stephan Mueller <smueller@xxxxxxxxxx>

commit bd6227a150fdb56e7bb734976ef6e53a2c1cb334 upstream.

During the change to use aligned buffers, the deallocation code path was
not updated correctly. The current code tries to free the aligned buffer
pointer and not the original buffer pointer as it is supposed to.

Thus, the code is updated to free the original buffer pointer and set
the aligned buffer pointer that is used throughout the code to NULL.

Fixes: 3cfc3b9721123 ("crypto: drbg - use aligned buffers")
CC: Herbert Xu <herbert@xxxxxxxxxxxxxxxxxxx>
Signed-off-by: Stephan Mueller <smueller@xxxxxxxxxx>
Signed-off-by: Herbert Xu <herbert@xxxxxxxxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
crypto/drbg.c | 8 ++++----
1 file changed, 4 insertions(+), 4 deletions(-)

--- a/crypto/drbg.c
+++ b/crypto/drbg.c
@@ -1133,10 +1133,10 @@ static inline void drbg_dealloc_state(st
{
if (!drbg)
return;
- kzfree(drbg->V);
- drbg->Vbuf = NULL;
- kzfree(drbg->C);
- drbg->Cbuf = NULL;
+ kzfree(drbg->Vbuf);
+ drbg->V = NULL;
+ kzfree(drbg->Cbuf);
+ drbg->C = NULL;
kzfree(drbg->scratchpadbuf);
drbg->scratchpadbuf = NULL;
drbg->reseed_ctr = 0;