From: Eric Biggers Date: Thu, 13 Jul 2017 12:16:56 +0000 (+0100) Subject: KEYS: DH: validate __spare field X-Git-Tag: v4.13-rc1~26^2~1 X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=4f9dabfaf8df971f8a3b6aa324f8f817be38d538;p=platform%2Fkernel%2Flinux-exynos.git KEYS: DH: validate __spare field Syscalls must validate that their reserved arguments are zero and return EINVAL otherwise. Otherwise, it will be impossible to actually use them for anything in the future because existing programs may be passing garbage in. This is standard practice when adding new APIs. Cc: stable@vger.kernel.org Signed-off-by: Eric Biggers Signed-off-by: David Howells Signed-off-by: James Morris --- diff --git a/security/keys/compat_dh.c b/security/keys/compat_dh.c index a6a659b..aa6b34c 100644 --- a/security/keys/compat_dh.c +++ b/security/keys/compat_dh.c @@ -33,6 +33,8 @@ long compat_keyctl_dh_compute(struct keyctl_dh_params __user *params, kdfcopy.hashname = compat_ptr(compat_kdfcopy.hashname); kdfcopy.otherinfo = compat_ptr(compat_kdfcopy.otherinfo); kdfcopy.otherinfolen = compat_kdfcopy.otherinfolen; + memcpy(kdfcopy.__spare, compat_kdfcopy.__spare, + sizeof(kdfcopy.__spare)); return __keyctl_dh_compute(params, buffer, buflen, &kdfcopy); } diff --git a/security/keys/dh.c b/security/keys/dh.c index 4755d4b..d1ea9f3 100644 --- a/security/keys/dh.c +++ b/security/keys/dh.c @@ -266,6 +266,11 @@ long __keyctl_dh_compute(struct keyctl_dh_params __user *params, if (kdfcopy) { char *hashname; + if (memchr_inv(kdfcopy->__spare, 0, sizeof(kdfcopy->__spare))) { + ret = -EINVAL; + goto out1; + } + if (buflen > KEYCTL_KDF_MAX_OUTPUT_LEN || kdfcopy->otherinfolen > KEYCTL_KDF_MAX_OI_LEN) { ret = -EMSGSIZE;