[PW_SID:810745] dpp: fix data corruption around prf_plus() call

[IWDTestBot]

Without the change test-dpp fails on aarch64-linux as:

$ unit/test-dpp
TEST: DPP test responder-only key derivation
TEST: DPP test mutual key derivation
TEST: DPP test PKEX key derivation
test-dpp: unit/test-dpp.c:514: test_pkex_key_derivation: Assertion `!memcmp(tmp, __tmp, 32)' failed.

This happens due to int/size_t type mismatch passed to vararg
parameters to prf_plus():

bool prf_plus(enum l_checksum_type type, const void *key, size_t key_len,
           void *out, size_t out_len,
           size_t n_extra, ...)
{
   // ...
   va_start(va, n_extra);

   for (i = 0; i < n_extra; i++) {
           iov[i + 1].iov_base = va_arg(va, void *);
           iov[i + 1].iov_len = va_arg(va, size_t);
   // ...

Note that varargs here could only be a sequence of void * / size_t
values.

But in src/dpp-util.c iwd attempted to pass int there:

prf_plus(sha, prk, bytes, z_out, bytes, 5,
mac_i, 6, // <- here
mac_r, 6, // <- and here
m_x, bytes,
n_x, bytes,
key, strlen(key));

aarch64 stores only 32-bit value part of the register:

mov     w7, #0x6
str     w7, [sp, #...]

and loads full 64-bit form of the register:

ldr     x3, [x3]

As a result higher bits of iov[].iov_len contain unexpected values and
sendmsg sends a lot more data than expected to the kernel.

The change fixes test-dpp test for me.

While at it fixed obvious int / size_t mismatch in src/erp.c.

src/dpp-util.c | 5 +++--
src/erp.c | 2 +-
2 files changed, 4 insertions(+), 3 deletions(-)

[IWDTestBot]

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[IWDTestBot]

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Test ID: fetch
Desc: Fetch the PR commits for this CI run
Duration: 2.32 seconds
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GitLint
Test ID: gitlint
Desc: Run gitlint with rule in .gitlint
Duration: 0.29 seconds
Result: FAIL

Output:

dpp: fix data corruption around prf_plus() call
9: B1 Line exceeds max length (104>80): "    test-dpp: unit/test-dpp.c:514: test_pkex_key_derivation: Assertion `!memcmp(tmp, __tmp, 32)' failed."

Make Distcheck
Test ID: makedistcheck
Desc: Run distcheck to check the distribution
Duration: 37.48 seconds
Result: PASS

Build - Configure
Test ID: build
Desc: Configure the BlueZ source tree
Duration: 8.83 seconds
Result: PASS

Make Check
Test ID: makecheck
Desc: Run 'make check'
Duration: 5.22 seconds
Result: PASS

Make Check w/Valgrind
Test ID: makecheckvalgrind
Desc: Run 'make check' with Valgrind
Duration: 59.87 seconds
Result: PASS

Incremental Build with patches
Test ID: incremental_build
Desc: Incremental build per patch in the series
Duration: 0.30 seconds
Result: PASS

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Desc: Runs IWD's autotest framework
Duration: 1664.39 seconds
Result: PASS

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Desc: Build IWD using clang compiler
Duration: 65.13 seconds
Result: PASS