From: Jamie Lokier <jamie@shareable.org>
To: Linus Torvalds <torvalds@osdl.org>
Cc: chris@scary.beasts.org, akpm@osdl.org, linux-kernel@vger.kernel.org
Subject: Re: Nasty 2.6 sendfile() bug / regression; affects vsftpd
Date: Mon, 19 Apr 2004 01:46:57 +0100 [thread overview]
Message-ID: <20040419004657.GD11064@mail.shareable.org> (raw)
In-Reply-To: <Pine.LNX.4.58.0404172005260.23917@ppc970.osdl.org>
Looking at related code, sys_sendfile64 a few lines down.
if (unlikely(copy_from_user(&pos, offset, sizeof(loff_t))))
return -EFAULT;
if (unlikely(put_user(pos, offset)))
return -EFAULT;
It seems odd that put_user() is used to write an 8-byte value, but
get_user() cannot be used read one. I looked in <asm-i386/uaccess.h>
and indeed the asymmetry is there.
Is there a reason why put_user() supports 1/2/4/8 bytes and get_user()
supports only 1/2/4 bytes?
-- Jamie
next prev parent reply other threads:[~2004-04-19 0:47 UTC|newest]
Thread overview: 13+ messages / expand[flat|nested] mbox.gz Atom feed top
2004-04-18 0:28 Nasty 2.6 sendfile() bug / regression; affects vsftpd chris
2004-04-18 3:12 ` Linus Torvalds
2004-04-18 13:49 ` chris
2004-04-19 0:46 ` Jamie Lokier [this message]
2004-04-19 5:28 ` Linus Torvalds
2004-04-19 9:44 ` [PATCH] Add 64-bit get_user and __get_user for i386 Jamie Lokier
2004-04-19 10:14 ` Jamie Lokier
2004-04-19 10:17 ` [PATCH] Use get_user for 64-bit read in sendfile64 Jamie Lokier
2004-04-19 10:36 ` Jamie Lokier
2004-04-19 14:56 ` [PATCH] Add 64-bit get_user and __get_user for i386 Linus Torvalds
[not found] ` <20040420020922.GA18348@mail.shareable.org>
[not found] ` <Pine.LNX.4.58.0404191945490.29941@ppc970.osdl.org>
2004-04-20 17:41 ` Jamie Lokier
2004-04-21 1:15 ` Linus Torvalds
2004-04-20 23:21 ` Jim Wilson
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20040419004657.GD11064@mail.shareable.org \
--to=jamie@shareable.org \
--cc=akpm@osdl.org \
--cc=chris@scary.beasts.org \
--cc=linux-kernel@vger.kernel.org \
--cc=torvalds@osdl.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.