Commit 16287397 authored May 03, 2022 by Ondrej Mosnacek Committed by Herbert Xu May 13, 2022

crypto: qcom-rng - fix infinite loop on requests not multiple of WORD_SZ



The commit referenced in the Fixes tag removed the 'break' from the else
branch in qcom_rng_read(), causing an infinite loop whenever 'max' is
not a multiple of WORD_SZ. This can be reproduced e.g. by running:

    kcapi-rng -b 67 >/dev/null

There are many ways to fix this without adding back the 'break', but
they all seem more awkward than simply adding it back, so do just that.

Tested on a machine with Qualcomm Amberwing processor.

Fixes: a680b183 ("crypto: qcom-rng - ensure buffer for generate is completely filled")
Cc: stable@vger.kernel.org
Signed-off-by: Ondrej Mosnacek <omosnace@redhat.com>
Reviewed-by: Brian Masney <bmasney@redhat.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

parent 31231092

drivers/crypto/qcom-rng.c

+1 −0

Original line number	Diff line number	Diff line
		@@ -65,6 +65,7 @@ static int qcom_rng_read(struct qcom_rng rng, u8 data, unsigned int max)
		} else {
		/* copy only remaining bytes */
		memcpy(data, &val, max - currsize);
		break;
		}
		} while (currsize < max);