crypto: drbg - Fix returning success on failure in CTR_DRBG

Eric Biggers · gregkh · commit 75597e8774f3 · 2026-07-24T15:54:28.000+02:00
commit 39a31ad upstream. drbg_ctr_generate() sometimes returns success when it fails, leaving the output buffer uninitialized. Fix it. Fixes: cde001e ("crypto: rng - RNGs must return 0 in success case") Cc: stable@vger.kernel.org Signed-off-by: Eric Biggers <ebiggers@kernel.org> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
diff --git a/crypto/drbg.c b/crypto/drbg.c
@@ -603,7 +603,7 @@ static int drbg_ctr_generate(struct drbg_state *drbg,
 	if (addtl && !list_empty(addtl)) {
 		ret = drbg_ctr_update(drbg, addtl, 2);
 		if (ret)
-			return 0;
+			return ret;
 	}
 
 	/* 10.2.1.5.2 step 4.1 */

Original file line number	Diff line number	Diff line change
`@@ -603,7 +603,7 @@ static int drbg_ctr_generate(struct drbg_state *drbg,`
`603`	`603`	`if (addtl && !list_empty(addtl)) {`
`604`	`604`	`ret = drbg_ctr_update(drbg, addtl, 2);`
`605`	`605`	`if (ret)`
`606`		`- return 0;`
	`606`	`+ return ret;`
`607`	`607`	`}`
`608`	`608`
`609`	`609`	`/* 10.2.1.5.2 step 4.1 */`