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 <axboe@kernel.dk>
This commit is contained in:
Jens Axboe 2019-05-14 16:02:22 -06:00
parent 61939b12dc
commit 87e5e6dab6
7 changed files with 31 additions and 27 deletions

View File

@ -1479,8 +1479,9 @@ static int aio_prep_rw(struct kiocb *req, const struct iocb *iocb)
return 0; return 0;
} }
static int aio_setup_rw(int rw, const struct iocb *iocb, struct iovec **iovec, static ssize_t aio_setup_rw(int rw, const struct iocb *iocb,
bool vectored, bool compat, struct iov_iter *iter) struct iovec **iovec, bool vectored, bool compat,
struct iov_iter *iter)
{ {
void __user *buf = (void __user *)(uintptr_t)iocb->aio_buf; void __user *buf = (void __user *)(uintptr_t)iocb->aio_buf;
size_t len = iocb->aio_nbytes; size_t len = iocb->aio_nbytes;
@ -1537,7 +1538,7 @@ static int aio_read(struct kiocb *req, const struct iocb *iocb,
return -EINVAL; return -EINVAL;
ret = aio_setup_rw(READ, iocb, &iovec, vectored, compat, &iter); ret = aio_setup_rw(READ, iocb, &iovec, vectored, compat, &iter);
if (ret) if (ret < 0)
return ret; return ret;
ret = rw_verify_area(READ, file, &req->ki_pos, iov_iter_count(&iter)); ret = rw_verify_area(READ, file, &req->ki_pos, iov_iter_count(&iter));
if (!ret) if (!ret)
@ -1565,7 +1566,7 @@ static int aio_write(struct kiocb *req, const struct iocb *iocb,
return -EINVAL; return -EINVAL;
ret = aio_setup_rw(WRITE, iocb, &iovec, vectored, compat, &iter); ret = aio_setup_rw(WRITE, iocb, &iovec, vectored, compat, &iter);
if (ret) if (ret < 0)
return ret; return ret;
ret = rw_verify_area(WRITE, file, &req->ki_pos, iov_iter_count(&iter)); ret = rw_verify_area(WRITE, file, &req->ki_pos, iov_iter_count(&iter));
if (!ret) { if (!ret) {

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@ -1003,7 +1003,7 @@ static int io_import_fixed(struct io_ring_ctx *ctx, int rw,
return 0; return 0;
} }
static int io_import_iovec(struct io_ring_ctx *ctx, int rw, static ssize_t io_import_iovec(struct io_ring_ctx *ctx, int rw,
const struct sqe_submit *s, struct iovec **iovec, const struct sqe_submit *s, struct iovec **iovec,
struct iov_iter *iter) struct iov_iter *iter)
{ {
@ -1023,7 +1023,7 @@ static int io_import_iovec(struct io_ring_ctx *ctx, int rw,
opcode = READ_ONCE(sqe->opcode); opcode = READ_ONCE(sqe->opcode);
if (opcode == IORING_OP_READ_FIXED || if (opcode == IORING_OP_READ_FIXED ||
opcode == IORING_OP_WRITE_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; *iovec = NULL;
return ret; return ret;
} }
@ -1089,7 +1089,7 @@ static int io_read(struct io_kiocb *req, const struct sqe_submit *s,
struct iov_iter iter; struct iov_iter iter;
struct file *file; struct file *file;
size_t iov_count; size_t iov_count;
int ret; ssize_t ret;
ret = io_prep_rw(req, s, force_nonblock); ret = io_prep_rw(req, s, force_nonblock);
if (ret) if (ret)
@ -1102,7 +1102,7 @@ static int io_read(struct io_kiocb *req, const struct sqe_submit *s,
return -EINVAL; return -EINVAL;
ret = io_import_iovec(req->ctx, READ, s, &iovec, &iter); ret = io_import_iovec(req->ctx, READ, s, &iovec, &iter);
if (ret) if (ret < 0)
return ret; return ret;
iov_count = iov_iter_count(&iter); 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 iov_iter iter;
struct file *file; struct file *file;
size_t iov_count; size_t iov_count;
int ret; ssize_t ret;
ret = io_prep_rw(req, s, force_nonblock); ret = io_prep_rw(req, s, force_nonblock);
if (ret) if (ret)
@ -1149,7 +1149,7 @@ static int io_write(struct io_kiocb *req, const struct sqe_submit *s,
return -EINVAL; return -EINVAL;
ret = io_import_iovec(req->ctx, WRITE, s, &iovec, &iter); ret = io_import_iovec(req->ctx, WRITE, s, &iovec, &iter);
if (ret) if (ret < 0)
return ret; return ret;
iov_count = iov_iter_count(&iter); iov_count = iov_iter_count(&iter);

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@ -1356,7 +1356,7 @@ SYSCALL_DEFINE4(vmsplice, int, fd, const struct iovec __user *, uiov,
struct iovec iovstack[UIO_FASTIOV]; struct iovec iovstack[UIO_FASTIOV];
struct iovec *iov = iovstack; struct iovec *iov = iovstack;
struct iov_iter iter; struct iov_iter iter;
long error; ssize_t error;
struct fd f; struct fd f;
int type; int type;
@ -1367,7 +1367,7 @@ SYSCALL_DEFINE4(vmsplice, int, fd, const struct iovec __user *, uiov,
error = import_iovec(type, uiov, nr_segs, error = import_iovec(type, uiov, nr_segs,
ARRAY_SIZE(iovstack), &iov, &iter); ARRAY_SIZE(iovstack), &iov, &iter);
if (!error) { if (error >= 0) {
error = do_vmsplice(f.file, &iter, flags); error = do_vmsplice(f.file, &iter, flags);
kfree(iov); 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 iovstack[UIO_FASTIOV];
struct iovec *iov = iovstack; struct iovec *iov = iovstack;
struct iov_iter iter; struct iov_iter iter;
long error; ssize_t error;
struct fd f; struct fd f;
int type; 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, error = compat_import_iovec(type, iov32, nr_segs,
ARRAY_SIZE(iovstack), &iov, &iter); ARRAY_SIZE(iovstack), &iov, &iter);
if (!error) { if (error >= 0) {
error = do_vmsplice(f.file, &iter, flags); error = do_vmsplice(f.file, &iter, flags);
kfree(iov); kfree(iov);
} }

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@ -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, size_t hash_and_copy_to_iter(const void *addr, size_t bytes, void *hashp,
struct iov_iter *i); 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, unsigned nr_segs, unsigned fast_segs,
struct iovec **iov, struct iov_iter *i); struct iovec **iov, struct iov_iter *i);
#ifdef CONFIG_COMPAT #ifdef CONFIG_COMPAT
struct compat_iovec; 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, unsigned nr_segs, unsigned fast_segs,
struct iovec **iov, struct iov_iter *i); struct iovec **iov, struct iov_iter *i);
#endif #endif

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@ -1634,9 +1634,9 @@ EXPORT_SYMBOL(dup_iter);
* on-stack array was used or not (and regardless of whether this function * on-stack array was used or not (and regardless of whether this function
* returns an error or not). * 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, unsigned nr_segs, unsigned fast_segs,
struct iovec **iov, struct iov_iter *i) struct iovec **iov, struct iov_iter *i)
{ {
@ -1652,14 +1652,15 @@ int import_iovec(int type, const struct iovec __user * uvector,
} }
iov_iter_init(i, type, p, nr_segs, n); iov_iter_init(i, type, p, nr_segs, n);
*iov = p == *iov ? NULL : p; *iov = p == *iov ? NULL : p;
return 0; return n;
} }
EXPORT_SYMBOL(import_iovec); EXPORT_SYMBOL(import_iovec);
#ifdef CONFIG_COMPAT #ifdef CONFIG_COMPAT
#include <linux/compat.h> #include <linux/compat.h>
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, unsigned nr_segs, unsigned fast_segs,
struct iovec **iov, struct iov_iter *i) struct iovec **iov, struct iov_iter *i)
{ {
@ -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_iter_init(i, type, p, nr_segs, n);
*iov = p == *iov ? NULL : p; *iov = p == *iov ? NULL : p;
return 0; return n;
} }
#endif #endif

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@ -80,9 +80,10 @@ int get_compat_msghdr(struct msghdr *kmsg,
kmsg->msg_iocb = NULL; 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, compat_ptr(msg.msg_iov), msg.msg_iovlen,
UIO_FASTIOV, iov, &kmsg->msg_iter); UIO_FASTIOV, iov, &kmsg->msg_iter);
return err < 0 ? err : 0;
} }
/* Bleech... */ /* Bleech... */

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@ -2208,9 +2208,10 @@ static int copy_msghdr_from_user(struct msghdr *kmsg,
kmsg->msg_iocb = NULL; kmsg->msg_iocb = NULL;
return import_iovec(save_addr ? READ : WRITE, err = import_iovec(save_addr ? READ : WRITE,
msg.msg_iov, msg.msg_iovlen, msg.msg_iov, msg.msg_iovlen,
UIO_FASTIOV, iov, &kmsg->msg_iter); UIO_FASTIOV, iov, &kmsg->msg_iter);
return err < 0 ? err : 0;
} }
static int ___sys_sendmsg(struct socket *sock, struct user_msghdr __user *msg, static int ___sys_sendmsg(struct socket *sock, struct user_msghdr __user *msg,