crypto: Always initialize splitkeylen
When _FORTIFY_SOURCE=2, glibc version is 2.35, and GCC version is
12.1.0, the compiler complains as follows:
In file included from /usr/include/string.h:535,
from /home/alarm/q/var/qemu/include/qemu/osdep.h:99,
from ../crypto/block-luks.c:21:
In function 'memset',
inlined from 'qcrypto_block_luks_store_key' at ../crypto/block-luks.c:843:9:
/usr/include/bits/string_fortified.h:59:10: error: 'splitkeylen' may be used uninitialized [-Werror=maybe-uninitialized]
59 | return __builtin___memset_chk (__dest, __ch, __len,
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
60 | __glibc_objsize0 (__dest));
| ~~~~~~~~~~~~~~~~~~~~~~~~~~
../crypto/block-luks.c: In function 'qcrypto_block_luks_store_key':
../crypto/block-luks.c:699:12: note: 'splitkeylen' was declared here
699 | size_t splitkeylen;
| ^~~~~~~~~~~
It seems the compiler cannot see that splitkeylen will not be used
when splitkey is NULL. Suppress the warning by initializing splitkeylen
even when splitkey stays NULL.
Signed-off-by: Akihiko Odaki <akihiko.odaki@daynix.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
diff --git a/crypto/block-luks.c b/crypto/block-luks.c
index 5688783..2f59c3a 100644
--- a/crypto/block-luks.c
+++ b/crypto/block-luks.c
@@ -706,14 +706,14 @@
assert(slot_idx < QCRYPTO_BLOCK_LUKS_NUM_KEY_SLOTS);
slot = &luks->header.key_slots[slot_idx];
+ splitkeylen = luks->header.master_key_len * slot->stripes;
+
if (qcrypto_random_bytes(slot->salt,
QCRYPTO_BLOCK_LUKS_SALT_LEN,
errp) < 0) {
goto cleanup;
}
- splitkeylen = luks->header.master_key_len * slot->stripes;
-
/*
* Determine how many iterations are required to
* hash the user password while consuming 1 second of compute
