From 87e5e6dab6c2a21fab2620f37786276d202e2ce0 Mon Sep 17 00:00:00 2001 From: Jens Axboe Date: Tue, 14 May 2019 16:02:22 -0600 Subject: [PATCH] uio: make import_iovec()/compat_import_iovec() return bytes on success Currently these functions return < 0 on error, and 0 for success. Change that so that we return < 0 on error, but number of bytes for success. Some callers already treat the return value that way, others need a slight tweak. Signed-off-by: Jens Axboe --- fs/aio.c | 9 +++++---- fs/io_uring.c | 16 ++++++++-------- fs/splice.c | 8 ++++---- include/linux/uio.h | 4 ++-- lib/iov_iter.c | 15 ++++++++------- net/compat.c | 3 ++- net/socket.c | 3 ++- 7 files changed, 31 insertions(+), 27 deletions(-) diff --git a/fs/aio.c b/fs/aio.c index 3490d1fa0e16..41824c710b36 100644 --- a/fs/aio.c +++ b/fs/aio.c @@ -1479,8 +1479,9 @@ static int aio_prep_rw(struct kiocb *req, const struct iocb *iocb) return 0; } -static int aio_setup_rw(int rw, const struct iocb *iocb, struct iovec **iovec, - bool vectored, bool compat, struct iov_iter *iter) +static ssize_t aio_setup_rw(int rw, const struct iocb *iocb, + struct iovec **iovec, bool vectored, bool compat, + struct iov_iter *iter) { void __user *buf = (void __user *)(uintptr_t)iocb->aio_buf; size_t len = iocb->aio_nbytes; @@ -1537,7 +1538,7 @@ static int aio_read(struct kiocb *req, const struct iocb *iocb, return -EINVAL; ret = aio_setup_rw(READ, iocb, &iovec, vectored, compat, &iter); - if (ret) + if (ret < 0) return ret; ret = rw_verify_area(READ, file, &req->ki_pos, iov_iter_count(&iter)); if (!ret) @@ -1565,7 +1566,7 @@ static int aio_write(struct kiocb *req, const struct iocb *iocb, return -EINVAL; ret = aio_setup_rw(WRITE, iocb, &iovec, vectored, compat, &iter); - if (ret) + if (ret < 0) return ret; ret = rw_verify_area(WRITE, file, &req->ki_pos, iov_iter_count(&iter)); if (!ret) { diff --git a/fs/io_uring.c b/fs/io_uring.c index 0fbb486a320e..23e08c10f486 100644 --- a/fs/io_uring.c +++ b/fs/io_uring.c @@ -1003,9 +1003,9 @@ static int io_import_fixed(struct io_ring_ctx *ctx, int rw, return 0; } -static int io_import_iovec(struct io_ring_ctx *ctx, int rw, - const struct sqe_submit *s, struct iovec **iovec, - struct iov_iter *iter) +static ssize_t io_import_iovec(struct io_ring_ctx *ctx, int rw, + const struct sqe_submit *s, struct iovec **iovec, + struct iov_iter *iter) { const struct io_uring_sqe *sqe = s->sqe; void __user *buf = u64_to_user_ptr(READ_ONCE(sqe->addr)); @@ -1023,7 +1023,7 @@ static int io_import_iovec(struct io_ring_ctx *ctx, int rw, opcode = READ_ONCE(sqe->opcode); if (opcode == IORING_OP_READ_FIXED || opcode == IORING_OP_WRITE_FIXED) { - int ret = io_import_fixed(ctx, rw, sqe, iter); + ssize_t ret = io_import_fixed(ctx, rw, sqe, iter); *iovec = NULL; return ret; } @@ -1089,7 +1089,7 @@ static int io_read(struct io_kiocb *req, const struct sqe_submit *s, struct iov_iter iter; struct file *file; size_t iov_count; - int ret; + ssize_t ret; ret = io_prep_rw(req, s, force_nonblock); if (ret) @@ -1102,7 +1102,7 @@ static int io_read(struct io_kiocb *req, const struct sqe_submit *s, return -EINVAL; ret = io_import_iovec(req->ctx, READ, s, &iovec, &iter); - if (ret) + if (ret < 0) return ret; iov_count = iov_iter_count(&iter); @@ -1136,7 +1136,7 @@ static int io_write(struct io_kiocb *req, const struct sqe_submit *s, struct iov_iter iter; struct file *file; size_t iov_count; - int ret; + ssize_t ret; ret = io_prep_rw(req, s, force_nonblock); if (ret) @@ -1149,7 +1149,7 @@ static int io_write(struct io_kiocb *req, const struct sqe_submit *s, return -EINVAL; ret = io_import_iovec(req->ctx, WRITE, s, &iovec, &iter); - if (ret) + if (ret < 0) return ret; iov_count = iov_iter_count(&iter); diff --git a/fs/splice.c b/fs/splice.c index 14cb602d9a2f..98412721f056 100644 --- a/fs/splice.c +++ b/fs/splice.c @@ -1356,7 +1356,7 @@ SYSCALL_DEFINE4(vmsplice, int, fd, const struct iovec __user *, uiov, struct iovec iovstack[UIO_FASTIOV]; struct iovec *iov = iovstack; struct iov_iter iter; - long error; + ssize_t error; struct fd f; int type; @@ -1367,7 +1367,7 @@ SYSCALL_DEFINE4(vmsplice, int, fd, const struct iovec __user *, uiov, error = import_iovec(type, uiov, nr_segs, ARRAY_SIZE(iovstack), &iov, &iter); - if (!error) { + if (error >= 0) { error = do_vmsplice(f.file, &iter, flags); kfree(iov); } @@ -1382,7 +1382,7 @@ COMPAT_SYSCALL_DEFINE4(vmsplice, int, fd, const struct compat_iovec __user *, io struct iovec iovstack[UIO_FASTIOV]; struct iovec *iov = iovstack; struct iov_iter iter; - long error; + ssize_t error; struct fd f; int type; @@ -1393,7 +1393,7 @@ COMPAT_SYSCALL_DEFINE4(vmsplice, int, fd, const struct compat_iovec __user *, io error = compat_import_iovec(type, iov32, nr_segs, ARRAY_SIZE(iovstack), &iov, &iter); - if (!error) { + if (error >= 0) { error = do_vmsplice(f.file, &iter, flags); kfree(iov); } diff --git a/include/linux/uio.h b/include/linux/uio.h index 2d0131ad4604..a61ceb6575ab 100644 --- a/include/linux/uio.h +++ b/include/linux/uio.h @@ -279,13 +279,13 @@ bool csum_and_copy_from_iter_full(void *addr, size_t bytes, __wsum *csum, struct size_t hash_and_copy_to_iter(const void *addr, size_t bytes, void *hashp, struct iov_iter *i); -int import_iovec(int type, const struct iovec __user * uvector, +ssize_t import_iovec(int type, const struct iovec __user * uvector, unsigned nr_segs, unsigned fast_segs, struct iovec **iov, struct iov_iter *i); #ifdef CONFIG_COMPAT struct compat_iovec; -int compat_import_iovec(int type, const struct compat_iovec __user * uvector, +ssize_t compat_import_iovec(int type, const struct compat_iovec __user * uvector, unsigned nr_segs, unsigned fast_segs, struct iovec **iov, struct iov_iter *i); #endif diff --git a/lib/iov_iter.c b/lib/iov_iter.c index f99c41d4eb54..f1e0569b4539 100644 --- a/lib/iov_iter.c +++ b/lib/iov_iter.c @@ -1634,9 +1634,9 @@ EXPORT_SYMBOL(dup_iter); * on-stack array was used or not (and regardless of whether this function * returns an error or not). * - * Return: 0 on success or negative error code on error. + * Return: Negative error code on error, bytes imported on success */ -int import_iovec(int type, const struct iovec __user * uvector, +ssize_t import_iovec(int type, const struct iovec __user * uvector, unsigned nr_segs, unsigned fast_segs, struct iovec **iov, struct iov_iter *i) { @@ -1652,16 +1652,17 @@ int import_iovec(int type, const struct iovec __user * uvector, } iov_iter_init(i, type, p, nr_segs, n); *iov = p == *iov ? NULL : p; - return 0; + return n; } EXPORT_SYMBOL(import_iovec); #ifdef CONFIG_COMPAT #include -int compat_import_iovec(int type, const struct compat_iovec __user * uvector, - unsigned nr_segs, unsigned fast_segs, - struct iovec **iov, struct iov_iter *i) +ssize_t compat_import_iovec(int type, + const struct compat_iovec __user * uvector, + unsigned nr_segs, unsigned fast_segs, + struct iovec **iov, struct iov_iter *i) { ssize_t n; struct iovec *p; @@ -1675,7 +1676,7 @@ int compat_import_iovec(int type, const struct compat_iovec __user * uvector, } iov_iter_init(i, type, p, nr_segs, n); *iov = p == *iov ? NULL : p; - return 0; + return n; } #endif diff --git a/net/compat.c b/net/compat.c index 3f9ce609397f..0f7ded26059e 100644 --- a/net/compat.c +++ b/net/compat.c @@ -80,9 +80,10 @@ int get_compat_msghdr(struct msghdr *kmsg, kmsg->msg_iocb = NULL; - return compat_import_iovec(save_addr ? READ : WRITE, + err = compat_import_iovec(save_addr ? READ : WRITE, compat_ptr(msg.msg_iov), msg.msg_iovlen, UIO_FASTIOV, iov, &kmsg->msg_iter); + return err < 0 ? err : 0; } /* Bleech... */ diff --git a/net/socket.c b/net/socket.c index 72372dc5dd70..bffec466b4f1 100644 --- a/net/socket.c +++ b/net/socket.c @@ -2208,9 +2208,10 @@ static int copy_msghdr_from_user(struct msghdr *kmsg, kmsg->msg_iocb = NULL; - return import_iovec(save_addr ? READ : WRITE, + err = import_iovec(save_addr ? READ : WRITE, msg.msg_iov, msg.msg_iovlen, UIO_FASTIOV, iov, &kmsg->msg_iter); + return err < 0 ? err : 0; } static int ___sys_sendmsg(struct socket *sock, struct user_msghdr __user *msg,