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* Typo in example code of process_vm_readv
@ 2014-08-16 11:35 Ville Ylenius
       [not found] ` <53EF41F4.2030509-xG8NWnMrmhjR7s880joybQ@public.gmane.org>
  0 siblings, 1 reply; 2+ messages in thread
From: Ville Ylenius @ 2014-08-16 11:35 UTC (permalink / raw)
  To: mtk.manpages-Re5JQEeQqe8AvxtiuMwx3w; +Cc: linux-man-u79uwXL29TY76Z2rM5mHXA

Hi,

there is a small typo in the example code of the man page of 
"process_vm_readv" 
(http://man7.org/linux/man-pages/man2/process_vm_readv.2.html):

        #include <sys/uio.h>

        int
        main(void)
        {
            struct iovec local[2];
            struct iovec remote[1];
            char buf1[10];
            char buf2[10];
            ssize_t nread;
            pid_t pid = 10;             /* PID of remote process */

            local[0].iov_base = buf1;
            local[0].iov_len = 10;
            local[1].iov_base = buf2;
            local[1].iov_len = 10;
            remote[0].iov_base = (void *) 0x10000;
            remote[1].iov_len = 20;                     /**** <---- TYPO: 1 --> 0 ****/

            nread = process_vm_readv(pid, local, 2, remote, 1, 0);
            if (nread != 20)
                return 1;
            else
                return 0;
        }


There is no two objects in "remote"-array so program corrupts other 
variables memory.

Please change

remote[1].iov_len = 20;

to

remote[0].iov_len = 20;

Thank you!

- Ville Ylenius
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^ permalink raw reply	[flat|nested] 2+ messages in thread

* Re: Typo in example code of process_vm_readv
       [not found] ` <53EF41F4.2030509-xG8NWnMrmhjR7s880joybQ@public.gmane.org>
@ 2014-08-17 15:53   ` Michael Kerrisk (man-pages)
  0 siblings, 0 replies; 2+ messages in thread
From: Michael Kerrisk (man-pages) @ 2014-08-17 15:53 UTC (permalink / raw)
  To: Ville Ylenius
  Cc: mtk.manpages-Re5JQEeQqe8AvxtiuMwx3w,
	linux-man-u79uwXL29TY76Z2rM5mHXA

On 08/16/2014 06:35 AM, Ville Ylenius wrote:
> Hi,
> 
> there is a small typo in the example code of the man page of 
> "process_vm_readv" 
> (http://man7.org/linux/man-pages/man2/process_vm_readv.2.html):
> 
>         #include <sys/uio.h>
> 
>         int
>         main(void)
>         {
>             struct iovec local[2];
>             struct iovec remote[1];
>             char buf1[10];
>             char buf2[10];
>             ssize_t nread;
>             pid_t pid = 10;             /* PID of remote process */
> 
>             local[0].iov_base = buf1;
>             local[0].iov_len = 10;
>             local[1].iov_base = buf2;
>             local[1].iov_len = 10;
>             remote[0].iov_base = (void *) 0x10000;
>             remote[1].iov_len = 20;                     /**** <---- TYPO: 1 --> 0 ****/
> 
>             nread = process_vm_readv(pid, local, 2, remote, 1, 0);
>             if (nread != 20)
>                 return 1;
>             else
>                 return 0;
>         }
> 
> 
> There is no two objects in "remote"-array so program corrupts other 
> variables memory.
> 
> Please change
> 
> remote[1].iov_len = 20;
> 
> to
> 
> remote[0].iov_len = 20;

Thanks, Ville. Fixed now.

Cheers,

Michael



-- 
Michael Kerrisk
Linux man-pages maintainer; http://www.kernel.org/doc/man-pages/
Linux/UNIX System Programming Training: http://man7.org/training/
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^ permalink raw reply	[flat|nested] 2+ messages in thread

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2014-08-16 11:35 Typo in example code of process_vm_readv Ville Ylenius
     [not found] ` <53EF41F4.2030509-xG8NWnMrmhjR7s880joybQ@public.gmane.org>
2014-08-17 15:53   ` Michael Kerrisk (man-pages)

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