[PATCH 1/3] net: Remove support for AIO on sockets
From: Demi Marie Obenour <hidden>
Date: 2026-05-23 19:43:09
Also in:
io-uring, linux-crypto, linux-doc, linux-perf-users, lkml, netdev
Subsystem:
crypto api, io_uring, networking [general], networking [sockets], performance events subsystem, the rest · Maintainers:
Herbert Xu, "David S. Miller", Jens Axboe, Eric Dumazet, Jakub Kicinski, Paolo Abeni, Kuniyuki Iwashima, Willem de Bruijn, Peter Zijlstra, Ingo Molnar, Arnaldo Carvalho de Melo, Namhyung Kim, Linus Torvalds
The only user of msg->msg_iocb was AF_ALG, but that's deprecated. It can be removed entirely at the cost of only supporting synchronous operations. This doesn't break userspace, which will silently block (for a bounded amount of time) in io_submit instead of operating asynchronously. This also makes struct msghdr smaller, helping every other caller of sendmsg(). Signed-off-by: Demi Marie Obenour <redacted> --- crypto/af_alg.c | 33 +------------- crypto/algif_aead.c | 39 ++++------------ crypto/algif_skcipher.c | 62 +++++--------------------- include/crypto/if_alg.h | 5 +-- include/linux/socket.h | 1 - io_uring/net.c | 1 - net/compat.c | 1 - net/socket.c | 7 +-- tools/perf/trace/beauty/include/linux/socket.h | 1 - 9 files changed, 25 insertions(+), 125 deletions(-)
diff --git a/crypto/af_alg.c b/crypto/af_alg.c
index 48c53f488e0fd30818e72439fe0c0d7e4cee1432..8ccf7a737cd6ca9a5d5bf47050c9afea0dfd61bf 100644
--- a/crypto/af_alg.c
+++ b/crypto/af_alg.c@@ -1085,35 +1085,6 @@ void af_alg_free_resources(struct af_alg_async_req *areq) } EXPORT_SYMBOL_GPL(af_alg_free_resources); -/** - * af_alg_async_cb - AIO callback handler - * @data: async request completion data - * @err: if non-zero, error result to be returned via ki_complete(); - * otherwise return the AIO output length via ki_complete(). - * - * This handler cleans up the struct af_alg_async_req upon completion of the - * AIO operation. - * - * The number of bytes to be generated with the AIO operation must be set - * in areq->outlen before the AIO callback handler is invoked. - */ -void af_alg_async_cb(void *data, int err) -{ - struct af_alg_async_req *areq = data; - struct sock *sk = areq->sk; - struct kiocb *iocb = areq->iocb; - unsigned int resultlen; - - /* Buffer size written by crypto operation. */ - resultlen = areq->outlen; - - af_alg_free_resources(areq); - sock_put(sk); - - iocb->ki_complete(iocb, err ? err : (int)resultlen); -} -EXPORT_SYMBOL_GPL(af_alg_async_cb); - /** * af_alg_poll - poll system call handler * @file: file pointer
@@ -1154,8 +1125,8 @@ struct af_alg_async_req *af_alg_alloc_areq(struct sock *sk, struct af_alg_ctx *ctx = alg_sk(sk)->private; struct af_alg_async_req *areq; - /* Only one AIO request can be in flight. */ - if (ctx->inflight) + /* Only one request can be in flight. */ + if (WARN_ON_ONCE(ctx->inflight)) return ERR_PTR(-EBUSY); areq = sock_kmalloc(sk, areqlen, GFP_KERNEL);
diff --git a/crypto/algif_aead.c b/crypto/algif_aead.c
index c6c2ce21895dd7df51dc825ed886ba7e1aa37130..60f06597cb0b13036bc975641a0b02ea8a41ad03 100644
--- a/crypto/algif_aead.c
+++ b/crypto/algif_aead.c@@ -197,37 +197,14 @@ static int _aead_recvmsg(struct socket *sock, struct msghdr *msg, aead_request_set_ad(&areq->cra_u.aead_req, ctx->aead_assoclen); aead_request_set_tfm(&areq->cra_u.aead_req, tfm); - if (msg->msg_iocb && !is_sync_kiocb(msg->msg_iocb)) { - /* AIO operation */ - sock_hold(sk); - areq->iocb = msg->msg_iocb; - - /* Remember output size that will be generated. */ - areq->outlen = outlen; - - aead_request_set_callback(&areq->cra_u.aead_req, - CRYPTO_TFM_REQ_MAY_SLEEP, - af_alg_async_cb, areq); - err = ctx->enc ? crypto_aead_encrypt(&areq->cra_u.aead_req) : - crypto_aead_decrypt(&areq->cra_u.aead_req); - - /* AIO operation in progress */ - if (err == -EINPROGRESS) - return -EIOCBQUEUED; - - sock_put(sk); - } else { - /* Synchronous operation */ - aead_request_set_callback(&areq->cra_u.aead_req, - CRYPTO_TFM_REQ_MAY_SLEEP | - CRYPTO_TFM_REQ_MAY_BACKLOG, - crypto_req_done, &ctx->wait); - err = crypto_wait_req(ctx->enc ? - crypto_aead_encrypt(&areq->cra_u.aead_req) : - crypto_aead_decrypt(&areq->cra_u.aead_req), - &ctx->wait); - } - + aead_request_set_callback(&areq->cra_u.aead_req, + CRYPTO_TFM_REQ_MAY_SLEEP | + CRYPTO_TFM_REQ_MAY_BACKLOG, + crypto_req_done, &ctx->wait); + err = crypto_wait_req(ctx->enc ? + crypto_aead_encrypt(&areq->cra_u.aead_req) : + crypto_aead_decrypt(&areq->cra_u.aead_req), + &ctx->wait); free: af_alg_free_resources(areq);
diff --git a/crypto/algif_skcipher.c b/crypto/algif_skcipher.c
index ba0a17fd95aca22aa58ebf510c7d9b5f0cea2c2e..9dbccabd87b13920c27aff5a450a235cc6a27d59 100644
--- a/crypto/algif_skcipher.c
+++ b/crypto/algif_skcipher.c@@ -79,20 +79,6 @@ static int algif_skcipher_export(struct sock *sk, struct skcipher_request *req) return err; } -static void algif_skcipher_done(void *data, int err) -{ - struct af_alg_async_req *areq = data; - struct sock *sk = areq->sk; - - if (err) - goto out; - - err = algif_skcipher_export(sk, &areq->cra_u.skcipher_req); - -out: - af_alg_async_cb(data, err); -} - static int _skcipher_recvmsg(struct socket *sock, struct msghdr *msg, size_t ignored, int flags) {
@@ -171,43 +157,19 @@ static int _skcipher_recvmsg(struct socket *sock, struct msghdr *msg, cflags |= CRYPTO_SKCIPHER_REQ_CONT; } - if (msg->msg_iocb && !is_sync_kiocb(msg->msg_iocb)) { - /* AIO operation */ - sock_hold(sk); - areq->iocb = msg->msg_iocb; + skcipher_request_set_callback(&areq->cra_u.skcipher_req, + cflags | + CRYPTO_TFM_REQ_MAY_SLEEP | + CRYPTO_TFM_REQ_MAY_BACKLOG, + crypto_req_done, &ctx->wait); + err = crypto_wait_req(ctx->enc ? + crypto_skcipher_encrypt(&areq->cra_u.skcipher_req) : + crypto_skcipher_decrypt(&areq->cra_u.skcipher_req), + &ctx->wait); - /* Remember output size that will be generated. */ - areq->outlen = len; - - skcipher_request_set_callback(&areq->cra_u.skcipher_req, - cflags | - CRYPTO_TFM_REQ_MAY_SLEEP, - algif_skcipher_done, areq); - err = ctx->enc ? - crypto_skcipher_encrypt(&areq->cra_u.skcipher_req) : - crypto_skcipher_decrypt(&areq->cra_u.skcipher_req); - - /* AIO operation in progress */ - if (err == -EINPROGRESS) - return -EIOCBQUEUED; - - sock_put(sk); - } else { - /* Synchronous operation */ - skcipher_request_set_callback(&areq->cra_u.skcipher_req, - cflags | - CRYPTO_TFM_REQ_MAY_SLEEP | - CRYPTO_TFM_REQ_MAY_BACKLOG, - crypto_req_done, &ctx->wait); - err = crypto_wait_req(ctx->enc ? - crypto_skcipher_encrypt(&areq->cra_u.skcipher_req) : - crypto_skcipher_decrypt(&areq->cra_u.skcipher_req), - &ctx->wait); - - if (!err) - err = algif_skcipher_export( - sk, &areq->cra_u.skcipher_req); - } + if (!err) + err = algif_skcipher_export( + sk, &areq->cra_u.skcipher_req); free: af_alg_free_resources(areq);
diff --git a/include/crypto/if_alg.h b/include/crypto/if_alg.h
index 0cc8fa749f68d2356789f72771c9e550b79e0b3d..62867daca47d76c9ea1a7ed233188788c5f6c3c0 100644
--- a/include/crypto/if_alg.h
+++ b/include/crypto/if_alg.h@@ -80,7 +80,6 @@ struct af_alg_rsgl { /** * struct af_alg_async_req - definition of crypto request - * @iocb: IOCB for AIO operations * @sk: Socket the request is associated with * @first_rsgl: First RX SG * @last_rsgl: Pointer to last RX SG
@@ -92,7 +91,6 @@ struct af_alg_rsgl { * @cra_u: Cipher request */ struct af_alg_async_req { - struct kiocb *iocb; struct sock *sk; struct af_alg_rsgl first_rsgl;
@@ -138,7 +136,7 @@ struct af_alg_async_req { * @write: True if we are in the middle of a write. * @init: True if metadata has been sent. * @len: Length of memory allocated for this data structure. - * @inflight: Non-zero when AIO requests are in flight. + * @inflight: Non-zero when requests are in flight, for debugging only. */ struct af_alg_ctx { struct list_head tsgl_list;
@@ -237,7 +235,6 @@ int af_alg_wait_for_data(struct sock *sk, unsigned flags, unsigned min); int af_alg_sendmsg(struct socket *sock, struct msghdr *msg, size_t size, unsigned int ivsize); void af_alg_free_resources(struct af_alg_async_req *areq); -void af_alg_async_cb(void *data, int err); __poll_t af_alg_poll(struct file *file, struct socket *sock, poll_table *wait); struct af_alg_async_req *af_alg_alloc_areq(struct sock *sk,
diff --git a/include/linux/socket.h b/include/linux/socket.h
index ec4a0a0257939a5363c55bed3ccb20182965b2e3..3ffdfe184b23d0a739e095407e956885d116c299 100644
--- a/include/linux/socket.h
+++ b/include/linux/socket.h@@ -89,7 +89,6 @@ struct msghdr { bool msg_get_inq : 1;/* return INQ after receive */ unsigned int msg_flags; /* flags on received message */ __kernel_size_t msg_controllen; /* ancillary data buffer length */ - struct kiocb *msg_iocb; /* ptr to iocb for async requests */ struct ubuf_info *msg_ubuf; int (*sg_from_iter)(struct sk_buff *skb, struct iov_iter *from, size_t length);
diff --git a/io_uring/net.c b/io_uring/net.c
index 30cd22c0b934b97ce6e265756b24daca7d398361..22100933966af547dfe6a52e69fc6882b4197234 100644
--- a/io_uring/net.c
+++ b/io_uring/net.c@@ -771,7 +771,6 @@ static int io_recvmsg_prep_setup(struct io_kiocb *req) kmsg->msg.msg_control = NULL; kmsg->msg.msg_get_inq = 1; kmsg->msg.msg_controllen = 0; - kmsg->msg.msg_iocb = NULL; kmsg->msg.msg_ubuf = NULL; if (req->flags & REQ_F_BUFFER_SELECT)
diff --git a/net/compat.c b/net/compat.c
index 2c9bd0edac997bc8c6ebd1bc8b92d8437ff32ea4..d68cf9c3aad5f7f1de84edbfffcf99d71e89292a 100644
--- a/net/compat.c
+++ b/net/compat.c@@ -75,7 +75,6 @@ int __get_compat_msghdr(struct msghdr *kmsg, if (msg->msg_iovlen > UIO_MAXIOV) return -EMSGSIZE; - kmsg->msg_iocb = NULL; kmsg->msg_ubuf = NULL; return 0; }
diff --git a/net/socket.c b/net/socket.c
index 22a412fdec079cf8fd829a15236de9daea09d2f2..9785363858cef0c4e6f0efc45b17c3d2add5a53c 100644
--- a/net/socket.c
+++ b/net/socket.c@@ -1213,8 +1213,7 @@ static ssize_t sock_read_iter(struct kiocb *iocb, struct iov_iter *to) { struct file *file = iocb->ki_filp; struct socket *sock = file->private_data; - struct msghdr msg = {.msg_iter = *to, - .msg_iocb = iocb}; + struct msghdr msg = {.msg_iter = *to}; ssize_t res; if (file->f_flags & O_NONBLOCK || (iocb->ki_flags & IOCB_NOWAIT))
@@ -1235,8 +1234,7 @@ static ssize_t sock_write_iter(struct kiocb *iocb, struct iov_iter *from) { struct file *file = iocb->ki_filp; struct socket *sock = file->private_data; - struct msghdr msg = {.msg_iter = *from, - .msg_iocb = iocb}; + struct msghdr msg = {.msg_iter = *from}; ssize_t res; if (iocb->ki_pos != 0)
@@ -2612,7 +2610,6 @@ int __copy_msghdr(struct msghdr *kmsg, if (msg->msg_iovlen > UIO_MAXIOV) return -EMSGSIZE; - kmsg->msg_iocb = NULL; kmsg->msg_ubuf = NULL; return 0; }
diff --git a/tools/perf/trace/beauty/include/linux/socket.h b/tools/perf/trace/beauty/include/linux/socket.h
index ec715ad4bf25f5f759d2cab3c6b796fed84df932..2a0a50fd66f41589f2699f7288a143873ce1bba6 100644
--- a/tools/perf/trace/beauty/include/linux/socket.h
+++ b/tools/perf/trace/beauty/include/linux/socket.h@@ -89,7 +89,6 @@ struct msghdr { bool msg_get_inq : 1;/* return INQ after receive */ unsigned int msg_flags; /* flags on received message */ __kernel_size_t msg_controllen; /* ancillary data buffer length */ - struct kiocb *msg_iocb; /* ptr to iocb for async requests */ struct ubuf_info *msg_ubuf; int (*sg_from_iter)(struct sk_buff *skb, struct iov_iter *from, size_t length);
--
2.54.0