linux-kernel - [RFC PATCH 02/12] fs/io_uring Don't use the return value from import

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [day] [month] [year] [list]

Message-ID: <87c31730ece341b0bdf29745b9411ab8@AcuMS.aculab.com>
Date:   Tue, 31 Mar 2020 13:52:29 +0000
From:   David Laight <David.Laight@...LAB.COM>
To:     Linux Kernel Mailing List <linux-kernel@...r.kernel.org>
Subject: [RFC PATCH 02/12] fs/io_uring Don't use the return value from
 import_iovec().

This is the only code that relies on import_iovec() returning
iter.count on success.
Not using the value actually saves passing it through to functions
that are also passed the 'iter'.
This allows a better interface to import_iovec().

Signed-off-by: David Laight <david.laight@...lab.com>
---
 fs/io_uring.c | 34 ++++++++++++++--------------------
 1 file changed, 14 insertions(+), 20 deletions(-)

diff --git a/fs/io_uring.c b/fs/io_uring.c
index 3affd96..d8dc2e2 100644
--- a/fs/io_uring.c
+++ b/fs/io_uring.c
@@ -2153,12 +2153,11 @@ static ssize_t loop_rw_iter(int rw, struct file *file, struct kiocb *kiocb,
 	return ret;
 }
 
-static void io_req_map_rw(struct io_kiocb *req, ssize_t io_size,
-			  struct iovec *iovec, struct iovec *fast_iov,
-			  struct iov_iter *iter)
+static void io_req_map_rw(struct io_kiocb *req, struct iovec *iovec,
+			  struct iovec *fast_iov, struct iov_iter *iter)
 {
 	req->io->rw.nr_segs = iter->nr_segs;
-	req->io->rw.size = io_size;
+	req->io->rw.size = iter->count;
 	req->io->rw.iov = iovec;
 	if (!req->io->rw.iov) {
 		req->io->rw.iov = req->io->rw.fast_iov;
@@ -2177,9 +2176,8 @@ static int io_alloc_async_ctx(struct io_kiocb *req)
 	return req->io == NULL;
 }
 
-static int io_setup_async_rw(struct io_kiocb *req, ssize_t io_size,
-			     struct iovec *iovec, struct iovec *fast_iov,
-			     struct iov_iter *iter)
+static int io_setup_async_rw(struct io_kiocb *req, struct iovec *iovec,
+			     struct iovec *fast_iov, struct iov_iter *iter)
 {
 	if (!io_op_defs[req->opcode].async_ctx)
 		return 0;
@@ -2187,7 +2185,7 @@ static int io_setup_async_rw(struct io_kiocb *req, ssize_t io_size,
 		if (io_alloc_async_ctx(req))
 			return -ENOMEM;
 
-		io_req_map_rw(req, io_size, iovec, fast_iov, iter);
+		io_req_map_rw(req, iovec, fast_iov, iter);
 	}
 	return 0;
 }
@@ -2218,7 +2216,7 @@ static int io_read_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe,
 	if (ret < 0)
 		return ret;
 
-	io_req_map_rw(req, ret, io->rw.iov, io->rw.fast_iov, &iter);
+	io_req_map_rw(req, io->rw.iov, io->rw.fast_iov, &iter);
 	return 0;
 }
 
@@ -2229,7 +2227,7 @@ static int io_read(struct io_kiocb *req, struct io_kiocb **nxt,
 	struct kiocb *kiocb = &req->rw.kiocb;
 	struct iov_iter iter;
 	size_t iov_count;
-	ssize_t io_size, ret;
+	ssize_t ret;
 
 	ret = io_import_iovec(READ, req, &iovec, &iter);
 	if (ret < 0)
@@ -2240,9 +2238,8 @@ static int io_read(struct io_kiocb *req, struct io_kiocb **nxt,
 		req->rw.kiocb.ki_flags &= ~IOCB_NOWAIT;
 
 	req->result = 0;
-	io_size = ret;
 	if (req->flags & REQ_F_LINK)
-		req->result = io_size;
+		req->result = iter.count;
 
 	/*
 	 * If the file doesn't support async, mark it as REQ_F_MUST_PUNT so
@@ -2268,8 +2265,7 @@ static int io_read(struct io_kiocb *req, struct io_kiocb **nxt,
 			kiocb_done(kiocb, ret2, nxt, req->in_async);
 		} else {
 copy_iov:
-			ret = io_setup_async_rw(req, io_size, iovec,
-						inline_vecs, &iter);
+			ret = io_setup_async_rw(req, iovec, inline_vecs, &iter);
 			if (ret)
 				goto out_free;
 			return -EAGAIN;
@@ -2307,7 +2303,7 @@ static int io_write_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe,
 	if (ret < 0)
 		return ret;
 
-	io_req_map_rw(req, ret, io->rw.iov, io->rw.fast_iov, &iter);
+	io_req_map_rw(req, io->rw.iov, io->rw.fast_iov, &iter);
 	return 0;
 }
 
@@ -2318,7 +2314,7 @@ static int io_write(struct io_kiocb *req, struct io_kiocb **nxt,
 	struct kiocb *kiocb = &req->rw.kiocb;
 	struct iov_iter iter;
 	size_t iov_count;
-	ssize_t ret, io_size;
+	ssize_t ret;
 
 	ret = io_import_iovec(WRITE, req, &iovec, &iter);
 	if (ret < 0)
@@ -2329,9 +2325,8 @@ static int io_write(struct io_kiocb *req, struct io_kiocb **nxt,
 		req->rw.kiocb.ki_flags &= ~IOCB_NOWAIT;
 
 	req->result = 0;
-	io_size = ret;
 	if (req->flags & REQ_F_LINK)
-		req->result = io_size;
+		req->result = iter.count;
 
 	/*
 	 * If the file doesn't support async, mark it as REQ_F_MUST_PUNT so
@@ -2381,8 +2376,7 @@ static int io_write(struct io_kiocb *req, struct io_kiocb **nxt,
 			kiocb_done(kiocb, ret2, nxt, req->in_async);
 		} else {
 copy_iov:
-			ret = io_setup_async_rw(req, io_size, iovec,
-						inline_vecs, &iter);
+			ret = io_setup_async_rw(req, iovec, inline_vecs, &iter);
 			if (ret)
 				goto out_free;
 			return -EAGAIN;
-- 
1.8.1.2

-
Registered Address Lakeside, Bramley Road, Mount Farm, Milton Keynes, MK1 1PT, UK
Registration No: 1397386 (Wales)