From: Ondrej Mosnacek Date: Tue, 3 May 2022 11:50:10 +0000 (+0200) Subject: crypto: qcom-rng - fix infinite loop on requests not multiple of WORD_SZ X-Git-Tag: v6.6.17~7571^2 X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=16287397ec5c08aa58db6acf7dbc55470d78087d;p=platform%2Fkernel%2Flinux-rpi.git 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: a680b1832ced ("crypto: qcom-rng - ensure buffer for generate is completely filled") Cc: stable@vger.kernel.org Signed-off-by: Ondrej Mosnacek Reviewed-by: Brian Masney Signed-off-by: Herbert Xu --- diff --git a/drivers/crypto/qcom-rng.c b/drivers/crypto/qcom-rng.c index 11f30fd..031b5f7 100644 --- a/drivers/crypto/qcom-rng.c +++ b/drivers/crypto/qcom-rng.c @@ -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);