On Wed, 2011-03-30 at 12:24 +0100, Daniel Baluta wrote:

We have:

quoted

UDP hash table entries: 128 (order: 0, 4096 bytes)
CONFIG_BASE_SMALL=0

udp_table_init looks like:

        if (!CONFIG_BASE_SMALL)
                table->hash = alloc_large_system_hash(name, .. &table->mask);
        /*
         * Make sure hash table has the minimum size
         */

Since CONFIG_BASE_SMALL is 0, we are allocating the hash using
alloc_large_system
Then:
        if (CONFIG_BASE_SMALL || table->mask < UDP_HTABLE_SIZE_MIN - 1) {
                table->hash = kmalloc();

table->mask is 127, and UDP_HTABLE_SIZE_MIN is 256, so we are allocating again
table->hash without freeing already allocated memory.

Indeed (on my ARM system the reported UDP hash table entries is 512, so
I don't get the memory leak).

We could free table->hash, before allocating the memory with kmalloc.
I don't fully understand the condition table->mask < UDP_HTABLE_SIZE_MIN - 1.

We don't have the equivalent of free_large_system_hash(). Reordering the
'if' blocks may be better.

-- 
Catalin


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