From mboxrd@z Thu Jan 1 00:00:00 1970 From: AKASHI Takahiro Date: Wed, 8 Jul 2020 10:30:24 +0900 Subject: [PATCH v2 08/17] efi_loader: signature: fix a size check against revocation list In-Reply-To: <20200708011238.GA16575@laputa> References: <20200609050947.17861-1-takahiro.akashi@linaro.org> <20200609050947.17861-9-takahiro.akashi@linaro.org> <84643027-6db0-db8e-f9bf-f9c21817f680@gmx.de> <20200708011238.GA16575@laputa> Message-ID: <20200708013024.GA18146@laputa> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: u-boot@lists.denx.de On Wed, Jul 08, 2020 at 10:12:38AM +0900, AKASHI Takahiro wrote: > On Fri, Jul 03, 2020 at 01:00:21PM +0200, Heinrich Schuchardt wrote: > > On 09.06.20 07:09, AKASHI Takahiro wrote: > > > Since the size check against an entry in efi_search_siglist() is > > > incorrect, this function will never find out a to-be-matched certificate > > > and its associated revocation time in the signature list. > > > > > > Signed-off-by: AKASHI Takahiro > > > --- > > > lib/efi_loader/efi_signature.c | 5 +++-- > > > 1 file changed, 3 insertions(+), 2 deletions(-) > > > > > > diff --git a/lib/efi_loader/efi_signature.c b/lib/efi_loader/efi_signature.c > > > index a05c75472721..f22dc151971f 100644 > > > --- a/lib/efi_loader/efi_signature.c > > > +++ b/lib/efi_loader/efi_signature.c > > > @@ -434,10 +434,11 @@ static bool efi_search_siglist(struct x509_certificate *cert, > > > * time64_t revocation_time; > > > * }; > > > */ > > > - if ((sig_data->size == SHA256_SUM_LEN) && > > > - !memcmp(sig_data->data, hash, SHA256_SUM_LEN)) { > > > + if ((sig_data->size >= SHA256_SUM_LEN + sizeof(time64_t)) && > > > + !memcmp(sig_data->data, msg, SHA256_SUM_LEN)) { > > > memcpy(revoc_time, sig_data->data + SHA256_SUM_LEN, > > > sizeof(*revoc_time)); > > > + EFI_PRINT("revocation time: %llu\n", *revoc_time); > > > > *revoc_time is of type __s64. So this must be %lld. Cf. > > > > include/linux/time.h:156 > > I know that because I added the definition. > Interestingly, linux added another type, timeu64_t, later on > to avoid an overflow in some calculation. > > While I don't think the current format is harmful, I will change it. Oops, I have already changed the format to "0x%llx" locally. I will stick to this. > -Takahiro Akashi > > > > Best regards > > > > Heinrich > > > > > found = true; > > > goto out; > > > } > > > > >