4.14-stable review patch. If anyone has any objections, please let me know.
------------------ From: Eric Biggers <[email protected]> commit 887207ed9e5812ed9239b6d07185a2d35dda91db upstream. af_alg_free_areq_sgls() If allocating the ->tsgl member of 'struct af_alg_async_req' failed, during cleanup we dereferenced the NULL ->tsgl pointer in af_alg_free_areq_sgls(), because ->tsgl_entries was nonzero. Fix it by only freeing the ->tsgl list if it is non-NULL. This affected both algif_skcipher and algif_aead. Fixes: e870456d8e7c ("crypto: algif_skcipher - overhaul memory management") Fixes: d887c52d6ae4 ("crypto: algif_aead - overhaul memory management") Reported-by: syzbot <[email protected]> Signed-off-by: Eric Biggers <[email protected]> Reviewed-by: Stephan Mueller <[email protected]> Signed-off-by: Herbert Xu <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]> --- crypto/af_alg.c | 13 +++++++------ 1 file changed, 7 insertions(+), 6 deletions(-) --- a/crypto/af_alg.c +++ b/crypto/af_alg.c @@ -699,14 +699,15 @@ void af_alg_free_areq_sgls(struct af_alg } tsgl = areq->tsgl; - for_each_sg(tsgl, sg, areq->tsgl_entries, i) { - if (!sg_page(sg)) - continue; - put_page(sg_page(sg)); - } + if (tsgl) { + for_each_sg(tsgl, sg, areq->tsgl_entries, i) { + if (!sg_page(sg)) + continue; + put_page(sg_page(sg)); + } - if (areq->tsgl && areq->tsgl_entries) sock_kfree_s(sk, tsgl, areq->tsgl_entries * sizeof(*tsgl)); + } } EXPORT_SYMBOL_GPL(af_alg_free_areq_sgls);
