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Fix FileCache::ChangeNumBlocks using memory after realloc shrink.

This commit is contained in:
Jonas 'Sortie' Termansen 2014-06-22 00:11:46 +02:00
parent 1830ab64ee
commit 8b3e25ce7f
1 changed files with 15 additions and 15 deletions
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30
kernel/fcache.cpp
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@ -448,6 +448,14 @@ bool FileCache::ChangeNumBlocks(size_t new_numblocks, bool exact)
if ( new_numblocks == blocks_used && !exact )
return true;
// Release blocks if the file has decreased in size.
if ( new_numblocks < blocks_used )
{
for ( size_t i = new_numblocks; i < blocks_used; i++ )
kernel_block_cache->ReleaseBlock(blocks[i]);
blocks_used = new_numblocks;
}
// If needed, adapt the length of the array containing block pointers.
if ( new_numblocks < blocks_length )
exact = true;
@ -458,26 +466,18 @@ bool FileCache::ChangeNumBlocks(size_t new_numblocks, bool exact)
BlockCacheBlock** new_blocks = (BlockCacheBlock**) realloc(blocks, size);
if ( !new_blocks )
{
if ( new_blocks_length < blocks_length )
new_blocks = blocks;
else
if ( blocks_length < new_blocks_length )
return false;
}
else
blocks = new_blocks,
blocks_length = new_blocks_length;
assert(!blocks_length || blocks);
// Release blocks if the file has decreased in size.
if ( new_numblocks < blocks_used )
{
for ( size_t i = new_numblocks; i < blocks_used; i++ )
kernel_block_cache->ReleaseBlock(blocks[i]);
blocks_used = new_numblocks;
return true;
blocks = new_blocks;
blocks_length = new_blocks_length;
}
assert(new_numblocks <= blocks_length);
assert(!blocks_length || blocks);
// Acquire more blocks if the file has increased in size.
for ( size_t i = blocks_used; i < new_numblocks; i++ )
{
@ -487,9 +487,9 @@ bool FileCache::ChangeNumBlocks(size_t new_numblocks, bool exact)
kernel_block_cache->ReleaseBlock(blocks[n]);
return false;
}
blocks_used++;
}
blocks_used = new_numblocks;
return true;
}