Hi Herbert, Changes v2: * import fix from Harsh Jain <harsh@xxxxxxxxxxx> to remove SG from list before freeing * fix return code used for ki_complete to match AIO behavior with sync behavior * rename variable list -> tsgl_list * update the algif_aead patch to include a dynamic TX SGL allocation similar to what algif_skcipher does. This allows concurrent continuous read/write operations to the extent you requested. Although I have not implemented "pairs of TX/RX SGLs" as I think that is even more overhead, the implementation conceptually defines such pairs. The recvmsg call defines how much from the input data is processed. The caller can have arbitrary number of sendmsg calls where the data is added to the TX SGL before an recvmsg asks the kernel to process a given amount (or all) of the TX SGL. With the changes, you will see a lot of code duplication now as I deliberately tried to use the same struct and variable names, the same function names and even the same oder of functions. If you agree to this patch, I volunteer to provide a followup patch that will extract the code duplication into common functions. Please find attached memory management updates to - simplify the code: the old AIO memory management is very complex and seemingly very fragile -- the update now eliminates all reported bugs in the skcipher and AEAD interfaces which allowed the kernel to be crashed by an unprivileged user - streamline the code: there is one code path for AIO and sync operation; the code between algif_skcipher and algif_aead is very similar (if that patch set is accepted, I volunteer to reduce code duplication by moving service operations into af_alg.c and to further unify the TX SGL handling) - unify the AIO and sync operation which only differ in the kernel crypto API callback and whether to wait for the crypto operation or not - fix all reported bugs regarding the handling of multiple IOCBs. The following testing was performed: - stress testing to verify that no memleaks exist - testing using Tadeusz Struck AIO test tool (see https://github.com/tstruk/afalg_async_test) -- the AEAD test is not applicable any more due to the changed user space interface; the skcipher test works once the user space interface change is honored in the test code - using the libkcapi test suite, all tests including the originally failing ones (AIO with multiple IOCBs) work now -- the current libkcapi code artificially limits the AEAD operation to one IOCB. After altering the libkcapi code to allow multiple IOCBs, the testing works flawless. Stephan Mueller (2): crypto: skcipher AF_ALG - overhaul memory management crypto: aead AF_ALG - overhaul memory management crypto/algif_aead.c | 668 +++++++++++++++++++++++++----------------------- crypto/algif_skcipher.c | 472 ++++++++++++++-------------------- 2 files changed, 544 insertions(+), 596 deletions(-) -- 2.9.3