Re: [PATCH] ptrace PTRACE_READDATA/WRITEDATA, kernel 2.5.62

[Manfred Spraul <manfred@colorfullife.com>]

On Mon, Feb 24, 2003 at 03:05:14PM +0100, fcorneli@elis.rug.ac.be wrote:

>+		ret = 0;
>+		res = ptrace_readdata(child, addr, (void *)addr2, data);
>+		if (res == data)
>+			break;
>  
>
You mention sparc - have you tested if that works on sparc?
ptrace_readdata assumes that addr2 is a pointer to kernel space, not 
user space. It works by chance on i386, but that's not acceptable for 
merging.
You must double buffer, check mem_read in fs/proc/base.c

Daniel wrote:

>Thirdly, I was going to do this, but I ended up making GDB use pread64
>on /dev/mem instead.  It works with no kernel modifications, and is
>just as fast.
>  
>
I assume you mean /proc/<pid>/mem. Performance is identical, same 
implementation.

--
    Manfred