[PATCH] crypto: nx - fix memory leaks in nx842_crypto_{alloc,free}_ctx

[Thorsten Blum <thorsten.blum@linux.dev>]

The bounce buffers are allocated with __get_free_pages() using
BOUNCE_BUFFER_ORDER (order 2 = 4 pages), but both the allocation error
path and nx842_crypto_free_ctx() release the buffers with free_page().
Use free_pages() with the matching order instead.

Also, since the scomp conversion, nx842_crypto_alloc_ctx() allocates the
context separately, but nx842_crypto_free_ctx() never releases it. Add
the missing kfree(ctx) in nx842_crypto_free_ctx(), and reuse
nx842_crypto_free_ctx() in the allocation error path.

Fixes: ed70b479c2c0 ("crypto: nx - add hardware 842 crypto comp alg")
Fixes: 980b5705f4e7 ("crypto: nx - Migrate to scomp API")
Cc: stable@vger.kernel.org
Signed-off-by: Thorsten Blum <thorsten.blum@linux.dev>
---
 drivers/crypto/nx/nx-842.c | 10 ++++------
 1 file changed, 4 insertions(+), 6 deletions(-)

diff --git a/drivers/crypto/nx/nx-842.c b/drivers/crypto/nx/nx-842.c
index b61f2545e165..a61208cbcd27 100644
--- a/drivers/crypto/nx/nx-842.c
+++ b/drivers/crypto/nx/nx-842.c
@@ -115,10 +115,7 @@ void *nx842_crypto_alloc_ctx(struct nx842_driver *driver)
 	ctx->sbounce = (u8 *)__get_free_pages(GFP_KERNEL, BOUNCE_BUFFER_ORDER);
 	ctx->dbounce = (u8 *)__get_free_pages(GFP_KERNEL, BOUNCE_BUFFER_ORDER);
 	if (!ctx->wmem || !ctx->sbounce || !ctx->dbounce) {
-		kfree(ctx->wmem);
-		free_page((unsigned long)ctx->sbounce);
-		free_page((unsigned long)ctx->dbounce);
-		kfree(ctx);
+		nx842_crypto_free_ctx(ctx);
 		return ERR_PTR(-ENOMEM);
 	}
 
@@ -131,8 +128,9 @@ void nx842_crypto_free_ctx(void *p)
 	struct nx842_crypto_ctx *ctx = p;
 
 	kfree(ctx->wmem);
-	free_page((unsigned long)ctx->sbounce);
-	free_page((unsigned long)ctx->dbounce);
+	free_pages((unsigned long)ctx->sbounce, BOUNCE_BUFFER_ORDER);
+	free_pages((unsigned long)ctx->dbounce, BOUNCE_BUFFER_ORDER);
+	kfree(ctx);
 }
 EXPORT_SYMBOL_GPL(nx842_crypto_free_ctx);