From 560efa7fca4f4f5bd390e54d43cd2cd1831c60cd Mon Sep 17 00:00:00 2001 From: Herbert Xu Date: Sat, 10 Aug 2024 14:20:59 +0800 Subject: [PATCH] crypto: dh - Check mpi_rshift errors Now that mpi_rshift can return errors, check them. Fixes: 35d2bf20683f ("crypto: dh - calculate Q from P for the full public key verification") Signed-off-by: Herbert Xu --- crypto/dh.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/crypto/dh.c b/crypto/dh.c index 68d11d66c0b5..afc0fd847761 100644 --- a/crypto/dh.c +++ b/crypto/dh.c @@ -145,9 +145,9 @@ static int dh_is_pubkey_valid(struct dh_ctx *ctx, MPI y) * ->p is odd, so no need to explicitly subtract one * from it before shifting to the right. */ - mpi_rshift(q, ctx->p, 1); + ret = mpi_rshift(q, ctx->p, 1) ?: + mpi_powm(val, y, q, ctx->p); - ret = mpi_powm(val, y, q, ctx->p); mpi_free(q); if (ret) { mpi_free(val); -- 2.20.1