Merge tag 'pull-fd' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs

Pull 'struct fd' class updates from Al Viro:
 "The bulk of struct fd memory safety stuff

  Making sure that struct fd instances are destroyed in the same scope
  where they'd been created, getting rid of reassignments and passing
  them by reference, converting to CLASS(fd{,_pos,_raw}).

  We are getting very close to having the memory safety of that stuff
  trivial to verify"

* tag 'pull-fd' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (28 commits)
  deal with the last remaing boolean uses of fd_file()
  css_set_fork(): switch to CLASS(fd_raw, ...)
  memcg_write_event_control(): switch to CLASS(fd)
  assorted variants of irqfd setup: convert to CLASS(fd)
  do_pollfd(): convert to CLASS(fd)
  convert do_select()
  convert vfs_dedupe_file_range().
  convert cifs_ioctl_copychunk()
  convert media_request_get_by_fd()
  convert spu_run(2)
  switch spufs_calls_{get,put}() to CLASS() use
  convert cachestat(2)
  convert do_preadv()/do_pwritev()
  fdget(), more trivial conversions
  fdget(), trivial conversions
  privcmd_ioeventfd_assign(): don't open-code eventfd_ctx_fdget()
  o2hb_region_dev_store(): avoid goto around fdget()/fdput()
  introduce "fd_pos" class, convert fdget_pos() users to it.
  fdget_raw() users: switch to CLASS(fd_raw)
  convert vmsplice() to CLASS(fd)
  ...

1 files changed, 52 insertions, 93 deletions

diff --git a/fs/read_write.c b/fs/read_write.c
index 3e5dad12a5b4..a6133241dfb8 100644
--- a/fs/read_write.c
+++ b/fs/read_write.c
@@ -386,8 +386,8 @@ EXPORT_SYMBOL(vfs_llseek);
 static off_t ksys_lseek(unsigned int fd, off_t offset, unsigned int whence)
 {
 	off_t retval;
-	struct fd f = fdget_pos(fd);
-	if (!fd_file(f))
+	CLASS(fd_pos, f)(fd);
+	if (fd_empty(f))
 		return -EBADF;
 
 	retval = -EINVAL;
@@ -397,7 +397,6 @@ static off_t ksys_lseek(unsigned int fd, off_t offset, unsigned int whence)
 		if (res != (loff_t)retval)
 			retval = -EOVERFLOW;	/* LFS: should only happen on 32 bit platforms */
 	}
-	fdput_pos(f);
 	return retval;
 }
 
@@ -420,15 +419,14 @@ SYSCALL_DEFINE5(llseek, unsigned int, fd, unsigned long, offset_high,
 		unsigned int, whence)
 {
 	int retval;
-	struct fd f = fdget_pos(fd);
+	CLASS(fd_pos, f)(fd);
 	loff_t offset;
 
-	if (!fd_file(f))
+	if (fd_empty(f))
 		return -EBADF;
 
-	retval = -EINVAL;
 	if (whence > SEEK_MAX)
-		goto out_putf;
+		return -EINVAL;
 
 	offset = vfs_llseek(fd_file(f), ((loff_t) offset_high << 32) | offset_low,
 			whence);
@@ -439,8 +437,6 @@ SYSCALL_DEFINE5(llseek, unsigned int, fd, unsigned long, offset_high,
 		if (!copy_to_user(result, &offset, sizeof(offset)))
 			retval = 0;
 	}
-out_putf:
-	fdput_pos(f);
 	return retval;
 }
 #endif
@@ -700,10 +696,10 @@ static inline loff_t *file_ppos(struct file *file)
 
 ssize_t ksys_read(unsigned int fd, char __user *buf, size_t count)
 {
-	struct fd f = fdget_pos(fd);
+	CLASS(fd_pos, f)(fd);
 	ssize_t ret = -EBADF;
 
-	if (fd_file(f)) {
+	if (!fd_empty(f)) {
 		loff_t pos, *ppos = file_ppos(fd_file(f));
 		if (ppos) {
 			pos = *ppos;
@@ -712,7 +708,6 @@ ssize_t ksys_read(unsigned int fd, char __user *buf, size_t count)
 		ret = vfs_read(fd_file(f), buf, count, ppos);
 		if (ret >= 0 && ppos)
 			fd_file(f)->f_pos = pos;
-		fdput_pos(f);
 	}
 	return ret;
 }
@@ -724,10 +719,10 @@ SYSCALL_DEFINE3(read, unsigned int, fd, char __user *, buf, size_t, count)
 
 ssize_t ksys_write(unsigned int fd, const char __user *buf, size_t count)
 {
-	struct fd f = fdget_pos(fd);
+	CLASS(fd_pos, f)(fd);
 	ssize_t ret = -EBADF;
 
-	if (fd_file(f)) {
+	if (!fd_empty(f)) {
 		loff_t pos, *ppos = file_ppos(fd_file(f));
 		if (ppos) {
 			pos = *ppos;
@@ -736,7 +731,6 @@ ssize_t ksys_write(unsigned int fd, const char __user *buf, size_t count)
 		ret = vfs_write(fd_file(f), buf, count, ppos);
 		if (ret >= 0 && ppos)
 			fd_file(f)->f_pos = pos;
-		fdput_pos(f);
 	}
 
 	return ret;
@@ -751,21 +745,17 @@ SYSCALL_DEFINE3(write, unsigned int, fd, const char __user *, buf,
 ssize_t ksys_pread64(unsigned int fd, char __user *buf, size_t count,
 		     loff_t pos)
 {
-	struct fd f;
-	ssize_t ret = -EBADF;
-
 	if (pos < 0)
 		return -EINVAL;
 
-	f = fdget(fd);
-	if (fd_file(f)) {
-		ret = -ESPIPE;
-		if (fd_file(f)->f_mode & FMODE_PREAD)
-			ret = vfs_read(fd_file(f), buf, count, &pos);
-		fdput(f);
-	}
+	CLASS(fd, f)(fd);
+	if (fd_empty(f))
+		return -EBADF;
 
-	return ret;
+	if (fd_file(f)->f_mode & FMODE_PREAD)
+		return vfs_read(fd_file(f), buf, count, &pos);
+
+	return -ESPIPE;
 }
 
 SYSCALL_DEFINE4(pread64, unsigned int, fd, char __user *, buf,
@@ -785,21 +775,17 @@ COMPAT_SYSCALL_DEFINE5(pread64, unsigned int, fd, char __user *, buf,
 ssize_t ksys_pwrite64(unsigned int fd, const char __user *buf,
 		      size_t count, loff_t pos)
 {
-	struct fd f;
-	ssize_t ret = -EBADF;
-
 	if (pos < 0)
 		return -EINVAL;
 
-	f = fdget(fd);
-	if (fd_file(f)) {
-		ret = -ESPIPE;
-		if (fd_file(f)->f_mode & FMODE_PWRITE)
-			ret = vfs_write(fd_file(f), buf, count, &pos);
-		fdput(f);
-	}
+	CLASS(fd, f)(fd);
+	if (fd_empty(f))
+		return -EBADF;
 
-	return ret;
+	if (fd_file(f)->f_mode & FMODE_PWRITE)
+		return vfs_write(fd_file(f), buf, count, &pos);
+
+	return -ESPIPE;
 }
 
 SYSCALL_DEFINE4(pwrite64, unsigned int, fd, const char __user *, buf,
@@ -1075,10 +1061,10 @@ out:
 static ssize_t do_readv(unsigned long fd, const struct iovec __user *vec,
 			unsigned long vlen, rwf_t flags)
 {
-	struct fd f = fdget_pos(fd);
+	CLASS(fd_pos, f)(fd);
 	ssize_t ret = -EBADF;
 
-	if (fd_file(f)) {
+	if (!fd_empty(f)) {
 		loff_t pos, *ppos = file_ppos(fd_file(f));
 		if (ppos) {
 			pos = *ppos;
@@ -1087,7 +1073,6 @@ static ssize_t do_readv(unsigned long fd, const struct iovec __user *vec,
 		ret = vfs_readv(fd_file(f), vec, vlen, ppos, flags);
 		if (ret >= 0 && ppos)
 			fd_file(f)->f_pos = pos;
-		fdput_pos(f);
 	}
 
 	if (ret > 0)
@@ -1099,10 +1084,10 @@ static ssize_t do_readv(unsigned long fd, const struct iovec __user *vec,
 static ssize_t do_writev(unsigned long fd, const struct iovec __user *vec,
 			 unsigned long vlen, rwf_t flags)
 {
-	struct fd f = fdget_pos(fd);
+	CLASS(fd_pos, f)(fd);
 	ssize_t ret = -EBADF;
 
-	if (fd_file(f)) {
+	if (!fd_empty(f)) {
 		loff_t pos, *ppos = file_ppos(fd_file(f));
 		if (ppos) {
 			pos = *ppos;
@@ -1111,7 +1096,6 @@ static ssize_t do_writev(unsigned long fd, const struct iovec __user *vec,
 		ret = vfs_writev(fd_file(f), vec, vlen, ppos, flags);
 		if (ret >= 0 && ppos)
 			fd_file(f)->f_pos = pos;
-		fdput_pos(f);
 	}
 
 	if (ret > 0)
@@ -1129,18 +1113,16 @@ static inline loff_t pos_from_hilo(unsigned long high, unsigned long low)
 static ssize_t do_preadv(unsigned long fd, const struct iovec __user *vec,
 			 unsigned long vlen, loff_t pos, rwf_t flags)
 {
-	struct fd f;
 	ssize_t ret = -EBADF;
 
 	if (pos < 0)
 		return -EINVAL;
 
-	f = fdget(fd);
-	if (fd_file(f)) {
+	CLASS(fd, f)(fd);
+	if (!fd_empty(f)) {
 		ret = -ESPIPE;
 		if (fd_file(f)->f_mode & FMODE_PREAD)
 			ret = vfs_readv(fd_file(f), vec, vlen, &pos, flags);
-		fdput(f);
 	}
 
 	if (ret > 0)
@@ -1152,18 +1134,16 @@ static ssize_t do_preadv(unsigned long fd, const struct iovec __user *vec,
 static ssize_t do_pwritev(unsigned long fd, const struct iovec __user *vec,
 			  unsigned long vlen, loff_t pos, rwf_t flags)
 {
-	struct fd f;
 	ssize_t ret = -EBADF;
 
 	if (pos < 0)
 		return -EINVAL;
 
-	f = fdget(fd);
-	if (fd_file(f)) {
+	CLASS(fd, f)(fd);
+	if (!fd_empty(f)) {
 		ret = -ESPIPE;
 		if (fd_file(f)->f_mode & FMODE_PWRITE)
 			ret = vfs_writev(fd_file(f), vec, vlen, &pos, flags);
-		fdput(f);
 	}
 
 	if (ret > 0)
@@ -1315,7 +1295,6 @@ COMPAT_SYSCALL_DEFINE6(pwritev2, compat_ulong_t, fd,
 static ssize_t do_sendfile(int out_fd, int in_fd, loff_t *ppos,
 			   size_t count, loff_t max)
 {
-	struct fd in, out;
 	struct inode *in_inode, *out_inode;
 	struct pipe_inode_info *opipe;
 	loff_t pos;
@@ -1326,35 +1305,32 @@ static ssize_t do_sendfile(int out_fd, int in_fd, loff_t *ppos,
 	/*
 	 * Get input file, and verify that it is ok..
 	 */
-	retval = -EBADF;
-	in = fdget(in_fd);
-	if (!fd_file(in))
-		goto out;
+	CLASS(fd, in)(in_fd);
+	if (fd_empty(in))
+		return -EBADF;
 	if (!(fd_file(in)->f_mode & FMODE_READ))
-		goto fput_in;
-	retval = -ESPIPE;
+		return -EBADF;
 	if (!ppos) {
 		pos = fd_file(in)->f_pos;
 	} else {
 		pos = *ppos;
 		if (!(fd_file(in)->f_mode & FMODE_PREAD))
-			goto fput_in;
+			return -ESPIPE;
 	}
 	retval = rw_verify_area(READ, fd_file(in), &pos, count);
 	if (retval < 0)
-		goto fput_in;
+		return retval;
 	if (count > MAX_RW_COUNT)
 		count =  MAX_RW_COUNT;
 
 	/*
 	 * Get output file, and verify that it is ok..
 	 */
-	retval = -EBADF;
-	out = fdget(out_fd);
-	if (!fd_file(out))
-		goto fput_in;
+	CLASS(fd, out)(out_fd);
+	if (fd_empty(out))
+		return -EBADF;
 	if (!(fd_file(out)->f_mode & FMODE_WRITE))
-		goto fput_out;
+		return -EBADF;
 	in_inode = file_inode(fd_file(in));
 	out_inode = file_inode(fd_file(out));
 	out_pos = fd_file(out)->f_pos;
@@ -1363,9 +1339,8 @@ static ssize_t do_sendfile(int out_fd, int in_fd, loff_t *ppos,
 		max = min(in_inode->i_sb->s_maxbytes, out_inode->i_sb->s_maxbytes);
 
 	if (unlikely(pos + count > max)) {
-		retval = -EOVERFLOW;
 		if (pos >= max)
-			goto fput_out;
+			return -EOVERFLOW;
 		count = max - pos;
 	}
 
@@ -1384,7 +1359,7 @@ static ssize_t do_sendfile(int out_fd, int in_fd, loff_t *ppos,
 	if (!opipe) {
 		retval = rw_verify_area(WRITE, fd_file(out), &out_pos, count);
 		if (retval < 0)
-			goto fput_out;
+			return retval;
 		retval = do_splice_direct(fd_file(in), &pos, fd_file(out), &out_pos,
 					  count, fl);
 	} else {
@@ -1410,12 +1385,6 @@ static ssize_t do_sendfile(int out_fd, int in_fd, loff_t *ppos,
 	inc_syscw(current);
 	if (pos > max)
 		retval = -EOVERFLOW;
-
-fput_out:
-	fdput(out);
-fput_in:
-	fdput(in);
-out:
 	return retval;
 }
 
@@ -1671,36 +1640,32 @@ SYSCALL_DEFINE6(copy_file_range, int, fd_in, loff_t __user *, off_in,
 {
 	loff_t pos_in;
 	loff_t pos_out;
-	struct fd f_in;
-	struct fd f_out;
 	ssize_t ret = -EBADF;
 
-	f_in = fdget(fd_in);
-	if (!fd_file(f_in))
-		goto out2;
+	CLASS(fd, f_in)(fd_in);
+	if (fd_empty(f_in))
+		return -EBADF;
 
-	f_out = fdget(fd_out);
-	if (!fd_file(f_out))
-		goto out1;
+	CLASS(fd, f_out)(fd_out);
+	if (fd_empty(f_out))
+		return -EBADF;
 
-	ret = -EFAULT;
 	if (off_in) {
 		if (copy_from_user(&pos_in, off_in, sizeof(loff_t)))
-			goto out;
+			return -EFAULT;
 	} else {
 		pos_in = fd_file(f_in)->f_pos;
 	}
 
 	if (off_out) {
 		if (copy_from_user(&pos_out, off_out, sizeof(loff_t)))
-			goto out;
+			return -EFAULT;
 	} else {
 		pos_out = fd_file(f_out)->f_pos;
 	}
 
-	ret = -EINVAL;
 	if (flags != 0)
-		goto out;
+		return -EINVAL;
 
 	ret = vfs_copy_file_range(fd_file(f_in), pos_in, fd_file(f_out), pos_out, len,
 				  flags);
@@ -1722,12 +1687,6 @@ SYSCALL_DEFINE6(copy_file_range, int, fd_in, loff_t __user *, off_in,
 			fd_file(f_out)->f_pos = pos_out;
 		}
 	}
-
-out:
-	fdput(f_out);
-out1:
-	fdput(f_in);
-out2:
 	return ret;
 }