iv/linux
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

hwrng: arm-smccc-trng - fix NO_ENTROPY handling

Browse Source 
[ Upstream commit 042b4b169c6fb9d4df268d66282d7302dd73d37b ]

The SMCCC_RET_TRNG_NO_ENTROPY switch arm is never used because the
NO_ENTROPY return value is negative and negative values are handled
above the switch by immediately returning.

Fix by handling errors using a default arm in the switch.

Fixes: 0888d04b47a1 ("hwrng: Add Arm SMCCC TRNG based driver")
Signed-off-by: James Cowgill <james.cowgill@blaize.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Sasha Levin <sashal@kernel.org>
This commit is contained in:
James Cowgill 2022-08-01 20:04:18 +00:00 committed by Greg Kroah-Hartman
parent 2720934713
commit 8ffe511b7d
1 changed files with 2 additions and 2 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

4
drivers/char/hw_random/arm_smccc_trng.c
View File

@ -71,8 +71,6 @@ static int smccc_trng_read(struct hwrng *rng, void *data, size_t max, bool wait)
MAX_BITS_PER_CALL);
arm_smccc_1_1_invoke(ARM_SMCCC_TRNG_RND, bits, &res);
if ((int)res.a0 < 0)
return (int)res.a0;
switch ((int)res.a0) {
case SMCCC_RET_SUCCESS:
@ -88,6 +86,8 @@ static int smccc_trng_read(struct hwrng *rng, void *data, size_t max, bool wait)
return copied;
cond_resched();
break;
default:
return -EIO;
}
}