Public/VeraCrypt
1
0
Fork 0
mirror of https://github.com/veracrypt/VeraCrypt.git synced 2025-11-11 11:08:02 -06:00
Code Activity

Static Code Analysis: in Windows Driver, avoid using uninitialized stack memory as random and use proper random value for wipe operation. Solve potential double-free issue.

Browse Source
This commit is contained in:
Mounir IDRASSI
2015-02-08 23:41:37 +01:00
parent 28a9eaf0e3
commit 516da2229d
3 changed files with 48 additions and 5 deletions
Download Patch File Download Diff File Expand all files Collapse all files

39
src/Driver/DriveFilter.c
View File

@@ -1176,6 +1176,36 @@ static VOID SetupThreadProc (PVOID threadArg)
KIRQL irql;
NTSTATUS status;
// generate real random values for wipeRandChars and
// wipeRandCharsUpdate instead of relying on uninitialized stack memory
LARGE_INTEGER iSeed;
KeQuerySystemTime( &iSeed );
if (KeGetCurrentIrql() < DISPATCH_LEVEL)
{
ULONG ulRandom;
ulRandom = RtlRandomEx( &iSeed.LowPart );
memcpy (wipeRandChars, &ulRandom, TC_WIPE_RAND_CHAR_COUNT);
ulRandom = RtlRandomEx( &ulRandom );
memcpy (wipeRandCharsUpdate, &ulRandom, TC_WIPE_RAND_CHAR_COUNT);
burn (&ulRandom, sizeof(ulRandom));
}
else
{
byte digest[SHA512_DIGESTSIZE];
sha512_ctx tctx;
sha512_begin (&tctx);
sha512_hash ((unsigned char *) &(iSeed.QuadPart), sizeof(iSeed.QuadPart), &tctx);
sha512_end (digest, &tctx);
memcpy (wipeRandChars, digest, TC_WIPE_RAND_CHAR_COUNT);
memcpy (wipeRandCharsUpdate, &digest[SHA512_DIGESTSIZE - TC_WIPE_RAND_CHAR_COUNT], TC_WIPE_RAND_CHAR_COUNT);
burn (digest, SHA512_DIGESTSIZE);
burn (&tctx, sizeof (tctx));
}
burn (&iSeed, sizeof(iSeed));
SetupResult = STATUS_UNSUCCESSFUL;
// Make sure volume header can be updated
@@ -1475,9 +1505,18 @@ err:
ret:
if (buffer)
{
burn (buffer, TC_ENCRYPTION_SETUP_IO_BLOCK_SIZE);
TCfree (buffer);
}
if (wipeBuffer)
{
burn (wipeBuffer, TC_ENCRYPTION_SETUP_IO_BLOCK_SIZE);
TCfree (wipeBuffer);
}
burn (wipeRandChars, TC_WIPE_RAND_CHAR_COUNT);
burn (wipeRandCharsUpdate, TC_WIPE_RAND_CHAR_COUNT);
SetupInProgress = FALSE;
PsTerminateSystemThread (SetupResult);