commit 12e6ad0db531bbdc0b134742798842a25cc929aa
author William A. Kennington III <wak@google.com> Tue Nov 02 15:32:13 2021 -0700
committer William A. Kennington III <wak@google.com> Wed Nov 03 04:24:31 2021 +0000
tree b02036b573c902c6ee66de6c1f28f11b707e4a8d
parent d2bcdd5cdc58e566be034f488b1dddcffd0303a4

libcr51sign: Fix struct size warning

The code is currently correct in the usage of the
signature_rsa4096_pkcs15 struct, but GCC infers that we could use
members past the end of the buffer it comes from.

Change-Id: I728e7361dd677fcce498857124dbe8908aaac64d
Signed-off-by: William A. Kennington III <wak@google.com>

subprojects/libcr51sign/src/libcr51sign.c

diff --git a/subprojects/libcr51sign/src/libcr51sign.c b/subprojects/libcr51sign/src/libcr51sign.c
index 06183d3..d89c88d 100644
--- a/subprojects/libcr51sign/src/libcr51sign.c
+++ b/subprojects/libcr51sign/src/libcr51sign.c
@@ -185,8 +185,6 @@
             read_len = SIGNATURE_OFFSET
         };
         uint8_t buffer[read_len];
-        // "modulus" & "signature" will not be indexed.
-        struct signature_rsa4096_pkcs15* sig_data = (void*)&buffer;
         int rv;
         rv = intf->read(ctx, signature_struct_offset, read_len, buffer);
         if (rv != LIBCR51SIGN_SUCCESS)
@@ -195,7 +193,7 @@
                     "validate_transition: failed to read signature struct");
             return LIBCR51SIGN_ERROR_RUNTIME_FAILURE;
         }
-        if (sig_data->signature_magic != SIGNATURE_MAGIC)
+        if (*(uint32_t*)buffer != SIGNATURE_MAGIC)
         {
             CPRINTS(ctx, "validate_transition: bad signature magic");
             return LIBCR51SIGN_ERROR_INVALID_DESCRIPTOR;