Re: [PATCH 0/3] crypto: qce - fix CCM AAD buffer leak and the AEAD error paths

[Eric Biggers <ebiggers@kernel.org>]

On Fri, Oct 16, 2026 at 10:09:42AM +0800, ZhaoJinming wrote:
> This series fixes a memory leak in the QCE AEAD driver together with two
> bugs in the error handling around it.
> 
> qce_aead_ccm_prepare_buf_assoclen() allocates rctx->adata for every CCM
> request that carries associated data, but the buffer is never freed.
> 
> While preparing that fix, two problems in the error path of
> qce_aead_async_req_handle() turned out to matter:
> 
>   - It unmaps req->src although rctx->src_sg is the scatterlist that was
>     passed to dma_map_sg().  For CCM requests with associated data,
>     rctx->src_sg carries the AAD buffer, so its mapping is leaked, and
>     freeing rctx->adata there would free memory that is still DMA-mapped.
> 
>   - A dma_map_sg() failure for the source scatterlist is not detected,
>     because the result is checked for a negative value while
>     dma_map_sg() returns 0 on failure.  The error path then unmaps a
>     scatterlist that was never mapped.
> 
> Patch 1 unmaps the correct scatterlist, patch 2 adds the missing frees
> and patch 3 fixes the dma_map_sg() check.
> 
> All three were reported as pre-existing in the Sashiko review of the QCE
> BAM locking series.  They touch the same function that was recently fixed
> by commit 7f2345f47dd1 ("crypto: qce - fix CCM AAD buffer
> underallocation").

Note that I reported these bugs (and others still unfixed) 3 months ago:
https://lore.kernel.org/linux-crypto/20260723183438.GB93534@quark/

- Eric