Re: [PATCH] kernel/sysctl.c: If "count" including the terminating byte '\0' the write system call should retrun success.

From: Steven Rostedt
Date: Wed Aug 26 2015 - 22:33:01 EST


On Thu, 27 Aug 2015 08:17:29 +0800
Sean Fu <fxinrong@xxxxxxxxx> wrote:

> On Thu, Aug 27, 2015 at 4:36 AM, Steven Rostedt <rostedt@xxxxxxxxxxx> wrote:
> > On Wed, 26 Aug 2015 23:48:01 +0800
> > Sean Fu <fxinrong@xxxxxxxxx> wrote:
> >
> >
> >> > Defending the patch, I can't imagine any user space code expecting the
> >> > current behavior. The current behavior is that if you write "1\0" it
> >> > will error out instead of accepting the "1". I can't come up with a
> >> > scenario that would require userspace to expect "1\0" to fail. Can you?
> >> Thanks
> >
> > Although, with the current patch, would "1\02" fail? It should.
> Yes, "1\02" is equal to "1\2"(count=2) or "1\2\0"(count=3), So it should fail.

Sorry, I meant "1\0 2"

-- Steve

>
> code
> len = write(fd, "1\0\2", 3);
>
> strace execute result:
> write(3, "1\2\0", 3) = -1 EINVAL (Invalid argument)
>
> >
> > -- Steve

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