Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit 0e665d5d authored by Al Viro's avatar Al Viro Committed by Linus Torvalds
Browse files

vfs: missed source of ->f_pos races 



compat_sys_{read,write}v() need the same "pass a copy of file->f_pos" thing
as sys_{read,write}{,v}().

Signed-off-by: default avatarAl Viro <viro@zeniv.linux.org.uk>
Cc: stable@kernel.org
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent 90785be3

fs/compat.c

+8 −2
Original line number Diff line number Diff line
@@ -1155,11 +1155,14 @@ compat_sys_readv(unsigned long fd, const struct compat_iovec __user *vec, 
	struct file *file;

	int fput_needed;

	ssize_t ret;

	loff_t pos;



	file = fget_light(fd, &fput_needed);

	if (!file)

		return -EBADF;

	ret = compat_readv(file, vec, vlen, &file->f_pos);

	pos = file->f_pos;

	ret = compat_readv(file, vec, vlen, &pos);

	file->f_pos = pos;

	fput_light(file, fput_needed);

	return ret;

}
@@ -1221,11 +1224,14 @@ compat_sys_writev(unsigned long fd, const struct compat_iovec __user *vec, 
	struct file *file;

	int fput_needed;

	ssize_t ret;

	loff_t pos;



	file = fget_light(fd, &fput_needed);

	if (!file)

		return -EBADF;

	ret = compat_writev(file, vec, vlen, &file->f_pos);

	pos = file->f_pos;

	ret = compat_writev(file, vec, vlen, &pos);

	file->f_pos = pos;

	fput_light(file, fput_needed);

	return ret;

}