[PATCH 4/9] iov_iter: transparently handle compat iovecs in import_iovec
From: Christoph Hellwig <hch@lst.de>
Date: 2020-09-23 06:07:15
Also in:
io-uring, keyrings, linux-arch, linux-arm-kernel, linux-block, linux-fsdevel, linux-mips, linux-mm, linux-s390, linux-scsi, linux-security-module, linuxppc-dev, lkml, sparclinux
Subsystem:
aio, block layer, filesystems (vfs and infrastructure), keys/keyrings, library code, memory management, memory management - misc, networking [general], scsi sg driver, scsi subsystem, security subsystem, the rest, userspace copyin/copyout (uiovec) · Maintainers:
Benjamin LaHaise, Jens Axboe, Alexander Viro, Christian Brauner, David Howells, Jarkko Sakkinen, Andrew Morton, David Hildenbrand, "David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Doug Gilbert, "James E.J. Bottomley", "Martin K. Petersen", Paul Moore, James Morris, "Serge E. Hallyn", Linus Torvalds
Use in compat_syscall to import either native or the compat iovecs, and remove the now superflous compat_import_iovec. This removes the need for special compat logic in most callers, and the remaining ones can still be simplified by using __import_iovec with a bool compat parameter. Signed-off-by: Christoph Hellwig <hch@lst.de> --- block/scsi_ioctl.c | 12 ++---------- drivers/scsi/sg.c | 9 +-------- fs/aio.c | 8 ++------ fs/io_uring.c | 20 ++++++++------------ fs/read_write.c | 6 ++++-- fs/splice.c | 2 +- include/linux/uio.h | 8 -------- lib/iov_iter.c | 14 ++------------ mm/process_vm_access.c | 3 ++- net/compat.c | 4 ++-- security/keys/compat.c | 5 ++--- 11 files changed, 26 insertions(+), 65 deletions(-)
diff --git a/block/scsi_ioctl.c b/block/scsi_ioctl.c
index ef722f04f88a93..e08df86866ee5d 100644
--- a/block/scsi_ioctl.c
+++ b/block/scsi_ioctl.c@@ -333,16 +333,8 @@ static int sg_io(struct request_queue *q, struct gendisk *bd_disk, struct iov_iter i; struct iovec *iov = NULL; -#ifdef CONFIG_COMPAT - if (in_compat_syscall()) - ret = compat_import_iovec(rq_data_dir(rq), - hdr->dxferp, hdr->iovec_count, - 0, &iov, &i); - else -#endif - ret = import_iovec(rq_data_dir(rq), - hdr->dxferp, hdr->iovec_count, - 0, &iov, &i); + ret = import_iovec(rq_data_dir(rq), hdr->dxferp, + hdr->iovec_count, 0, &iov, &i); if (ret < 0) goto out_free_cdb;
diff --git a/drivers/scsi/sg.c b/drivers/scsi/sg.c
index 20472aaaf630a4..bfa8d77322d732 100644
--- a/drivers/scsi/sg.c
+++ b/drivers/scsi/sg.c@@ -1820,14 +1820,7 @@ sg_start_req(Sg_request *srp, unsigned char *cmd) struct iovec *iov = NULL; struct iov_iter i; -#ifdef CONFIG_COMPAT - if (in_compat_syscall()) - res = compat_import_iovec(rw, hp->dxferp, iov_count, - 0, &iov, &i); - else -#endif - res = import_iovec(rw, hp->dxferp, iov_count, - 0, &iov, &i); + res = import_iovec(rw, hp->dxferp, iov_count, 0, &iov, &i); if (res < 0) return res;
diff --git a/fs/aio.c b/fs/aio.c
index d5ec303855669d..c45c20d875388c 100644
--- a/fs/aio.c
+++ b/fs/aio.c@@ -1489,12 +1489,8 @@ static ssize_t aio_setup_rw(int rw, const struct iocb *iocb, *iovec = NULL; return ret; } -#ifdef CONFIG_COMPAT - if (compat) - return compat_import_iovec(rw, buf, len, UIO_FASTIOV, iovec, - iter); -#endif - return import_iovec(rw, buf, len, UIO_FASTIOV, iovec, iter); + + return __import_iovec(rw, buf, len, UIO_FASTIOV, iovec, iter, compat); } static inline void aio_rw_done(struct kiocb *req, ssize_t ret)
diff --git a/fs/io_uring.c b/fs/io_uring.c
index 3790c7fe9fee22..ba84ecea7cb1a4 100644
--- a/fs/io_uring.c
+++ b/fs/io_uring.c@@ -2837,13 +2837,8 @@ static ssize_t __io_import_iovec(int rw, struct io_kiocb *req, return ret; } -#ifdef CONFIG_COMPAT - if (req->ctx->compat) - return compat_import_iovec(rw, buf, sqe_len, UIO_FASTIOV, - iovec, iter); -#endif - - return import_iovec(rw, buf, sqe_len, UIO_FASTIOV, iovec, iter); + return __import_iovec(rw, buf, sqe_len, UIO_FASTIOV, iovec, iter, + req->ctx->compat); } static ssize_t io_import_iovec(int rw, struct io_kiocb *req,
@@ -4179,8 +4174,9 @@ static int __io_recvmsg_copy_hdr(struct io_kiocb *req, sr->len); iomsg->iov = NULL; } else { - ret = import_iovec(READ, uiov, iov_len, UIO_FASTIOV, - &iomsg->iov, &iomsg->msg.msg_iter); + ret = __import_iovec(READ, uiov, iov_len, UIO_FASTIOV, + &iomsg->iov, &iomsg->msg.msg_iter, + false); if (ret > 0) ret = 0; }
@@ -4220,9 +4216,9 @@ static int __io_compat_recvmsg_copy_hdr(struct io_kiocb *req, sr->len = iomsg->iov[0].iov_len; iomsg->iov = NULL; } else { - ret = compat_import_iovec(READ, uiov, len, UIO_FASTIOV, - &iomsg->iov, - &iomsg->msg.msg_iter); + ret = __import_iovec(READ, (struct iovec __user *)uiov, len, + UIO_FASTIOV, &iomsg->iov, + &iomsg->msg.msg_iter, true); if (ret < 0) return ret; }
diff --git a/fs/read_write.c b/fs/read_write.c
index e5e891a88442ef..0a68037580b455 100644
--- a/fs/read_write.c
+++ b/fs/read_write.c@@ -1078,7 +1078,8 @@ static size_t compat_readv(struct file *file, struct iov_iter iter; ssize_t ret; - ret = compat_import_iovec(READ, vec, vlen, UIO_FASTIOV, &iov, &iter); + ret = import_iovec(READ, (const struct iovec __user *)vec, vlen, + UIO_FASTIOV, &iov, &iter); if (ret >= 0) { ret = do_iter_read(file, &iter, pos, flags); kfree(iov);
@@ -1186,7 +1187,8 @@ static size_t compat_writev(struct file *file, struct iov_iter iter; ssize_t ret; - ret = compat_import_iovec(WRITE, vec, vlen, UIO_FASTIOV, &iov, &iter); + ret = import_iovec(WRITE, (const struct iovec __user *)vec, vlen, + UIO_FASTIOV, &iov, &iter); if (ret >= 0) { file_start_write(file); ret = do_iter_write(file, &iter, pos, flags);
diff --git a/fs/splice.c b/fs/splice.c
index d7c8a7c4db07ff..132d42b9871f9b 100644
--- a/fs/splice.c
+++ b/fs/splice.c@@ -1387,7 +1387,7 @@ COMPAT_SYSCALL_DEFINE4(vmsplice, int, fd, const struct compat_iovec __user *, io if (error) return error; - error = compat_import_iovec(type, iov32, nr_segs, + error = import_iovec(type, (struct iovec __user *)iov32, nr_segs, ARRAY_SIZE(iovstack), &iov, &iter); if (error >= 0) { error = do_vmsplice(f.file, &iter, flags);
diff --git a/include/linux/uio.h b/include/linux/uio.h
index 92c11fe41c6228..daedc61ad3706e 100644
--- a/include/linux/uio.h
+++ b/include/linux/uio.h@@ -275,14 +275,6 @@ ssize_t import_iovec(int type, const struct iovec __user *uvec, ssize_t __import_iovec(int type, const struct iovec __user *uvec, unsigned nr_segs, unsigned fast_segs, struct iovec **iovp, struct iov_iter *i, bool compat); - -#ifdef CONFIG_COMPAT -struct compat_iovec; -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 - int import_single_range(int type, void __user *buf, size_t len, struct iovec *iov, struct iov_iter *i);
diff --git a/lib/iov_iter.c b/lib/iov_iter.c
index d5d8afe31fca16..8c51e1b03814a3 100644
--- a/lib/iov_iter.c
+++ b/lib/iov_iter.c@@ -1806,21 +1806,11 @@ ssize_t import_iovec(int type, const struct iovec __user *uvec, unsigned nr_segs, unsigned fast_segs, struct iovec **iovp, struct iov_iter *i) { - return __import_iovec(type, uvec, nr_segs, fast_segs, iovp, i, false); + return __import_iovec(type, uvec, nr_segs, fast_segs, iovp, i, + in_compat_syscall()); } EXPORT_SYMBOL(import_iovec); -#ifdef CONFIG_COMPAT -ssize_t compat_import_iovec(int type, const struct compat_iovec __user *uvec, - unsigned nr_segs, unsigned fast_segs, struct iovec **iovp, - struct iov_iter *i) -{ - return __import_iovec(type, (const struct iovec __user *)uvec, nr_segs, - fast_segs, iovp, i, true); -} -EXPORT_SYMBOL(compat_import_iovec); -#endif - int import_single_range(int rw, void __user *buf, size_t len, struct iovec *iov, struct iov_iter *i) {
diff --git a/mm/process_vm_access.c b/mm/process_vm_access.c
index 5e728c20c2bead..3f2156aab44263 100644
--- a/mm/process_vm_access.c
+++ b/mm/process_vm_access.c@@ -326,7 +326,8 @@ compat_process_vm_rw(compat_pid_t pid, if (flags != 0) return -EINVAL; - rc = compat_import_iovec(dir, lvec, liovcnt, UIO_FASTIOV, &iov_l, &iter); + rc = import_iovec(dir, (const struct iovec __user *)lvec, liovcnt, + UIO_FASTIOV, &iov_l, &iter); if (rc < 0) return rc; if (!iov_iter_count(&iter))
diff --git a/net/compat.c b/net/compat.c
index 95ce707a30a31d..ddd15af3a2837b 100644
--- a/net/compat.c
+++ b/net/compat.c@@ -98,8 +98,8 @@ int get_compat_msghdr(struct msghdr *kmsg, if (err) return err; - err = compat_import_iovec(save_addr ? READ : WRITE, compat_ptr(ptr), - len, UIO_FASTIOV, iov, &kmsg->msg_iter); + err = import_iovec(save_addr ? READ : WRITE, compat_ptr(ptr), len, + UIO_FASTIOV, iov, &kmsg->msg_iter); return err < 0 ? err : 0; }
diff --git a/security/keys/compat.c b/security/keys/compat.c
index 6ee9d8f6a4a5bb..7ae531db031cf8 100644
--- a/security/keys/compat.c
+++ b/security/keys/compat.c@@ -33,9 +33,8 @@ static long compat_keyctl_instantiate_key_iov( if (!_payload_iov) ioc = 0; - ret = compat_import_iovec(WRITE, _payload_iov, ioc, - ARRAY_SIZE(iovstack), &iov, - &from); + ret = import_iovec(WRITE, (const struct iovec __user *)_payload_iov, + ioc, ARRAY_SIZE(iovstack), &iov, &from); if (ret < 0) return ret;
--
2.28.0