Re: [PATCH -mm] Don't truncate /proc/PID/environ at 4096 characters

[Hugh Dickins]

On Wed, 19 Sep 2007, Mikael Pettersson wrote:
> H. Peter Anvin writes:
>  > Mikael Pettersson wrote:
>  > > Does /proc/PID/mem even work? If I do `strace cat /proc/PID/mem > /dev/null'
>  > > for a known good PID, the first read() from /proc/PID/mem fails with ESRCH,
>  > 
>  > Of course it does.  Address zero isn't typically mapped.
> 
> Indeed. My bad :-(

No, not quite.  Peter explains why "cat /proc/self/mem" gets EIO,
but you were seeing "cat /proc/other/mem" get ESRCH: that's from
the stringent !MAY_PTRACE || !ptrace_may_attach checks.

Hugh
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