summaryrefslogtreecommitdiffstats
path: root/crypto/bn
diff options
context:
space:
mode:
authorTomas Mraz <tmraz@fedoraproject.org>2020-05-19 10:51:53 +0200
committerTomas Mraz <tmraz@fedoraproject.org>2020-05-20 17:31:43 +0200
commit1d05eb55caa8965a151360c2469c463ecd990987 (patch)
tree7169299eedcf8781482028547e220ea2cae60b13 /crypto/bn
parentcbeb0bfa961412eebfbdf1e72900f05527e81e15 (diff)
Avoid potential overflow to the sign bit when shifting left 24 places
Although there are platforms where int is 64 bit, 2GiB large BIGNUMs instead of 4GiB should be "big enough for everybody". Reviewed-by: Richard Levitte <levitte@openssl.org> (Merged from https://github.com/openssl/openssl/pull/11857)
Diffstat (limited to 'crypto/bn')
-rw-r--r--crypto/bn/bn_mpi.c2
1 files changed, 1 insertions, 1 deletions
diff --git a/crypto/bn/bn_mpi.c b/crypto/bn/bn_mpi.c
index 504cddffec..d2be44e2bd 100644
--- a/crypto/bn/bn_mpi.c
+++ b/crypto/bn/bn_mpi.c
@@ -45,7 +45,7 @@ BIGNUM *BN_mpi2bn(const unsigned char *d, int n, BIGNUM *ain)
int neg = 0;
BIGNUM *a = NULL;
- if (n < 4) {
+ if (n < 4 || (d[0] & 0x80) != 0) {
BNerr(BN_F_BN_MPI2BN, BN_R_INVALID_LENGTH);
return NULL;
}