tree 5e27ea35e38ed49148cb5d3779c744677190888f
parent 0444b3035e5f4981f4d1d96f9f0c3cbada1e6d69
author David Howells <dhowells@redhat.com> 1174633800 -0700
committer Linus Torvalds <torvalds@woody.linux-foundation.org> 1174672881 -0700

[PATCH] FDPIC: fix the /proc/pid/stat representation of executable boundaries

Fix the /proc/pid/stat representation of executable boundaries.  It should
show the bounds of the executable, but instead shows the bounds of the
loader.

Before the patch is applied, the bug can be seen by examining, say, inetd:

	# ps | grep inetd
	  610         root          0   S   /usr/sbin/inetd -i
	# cat /proc/610/maps
	c0bb0000-c0bba788 r-xs 00000000 00:0b 14582157  /lib/ld-uClibc-0.9.28.so
	c3180000-c31dede4 r-xs 00000000 00:0b 14582179  /lib/libuClibc-0.9.28.so
	c328c000-c328ea00 rw-p 00008000 00:0b 14582157  /lib/ld-uClibc-0.9.28.so
	c3290000-c329b6c0 rw-p 00000000 00:00 0
	c32a0000-c32c0000 rwxp 00000000 00:00 0
	c32d4000-c32d8000 rw-p 00000000 00:00 0
	c3394000-c3398000 rw-p 00000000 00:00 0
	c3458000-c345f464 r-xs 00000000 00:0b 16384612  /usr/sbin/inetd
	c3470000-c34748f8 rw-p 00004000 00:0b 16384612  /usr/sbin/inetd
	c34cc000-c34d0000 rw-p 00000000 00:00 0
	c34d4000-c34d8000 rw-p 00000000 00:00 0
	c34d8000-c34dc000 rw-p 00000000 00:00 0
	# cat /proc/610/stat
	610 (inetd) S 1 610 610 0 -1 256 0 0 0 0 0 8 0 0 19 0 1 0 94392000718
	950272 0 4294967295 3233480704 3233523592 3274440352 3274439976
 	3273467584 0 0 4096 90115 3221712796 0 0 17 0 0 0 0

The code boundaries are 3233480704 to 3233523592, which are:

	(gdb) p/x 3233480704
	$1 = 0xc0bb0000
	(gdb) p/x 3233523592
	$2 = 0xc0bba788

Which corresponds to this line in the maps file:

	c0bb0000-c0bba788 r-xs 00000000 00:0b 14582157  /lib/ld-uClibc-0.9.28.so

Which is wrong.  After the patch is applied, the maps file is pretty much
identical (there's some minor shuffling of the location of some of the
anonymous VMAs), but the stat file is now:

	# cat /proc/610/stat
	610 (inetd) S 1 610 610 0 -1 256 0 0 0 0 0 7 0 0 18 0 1 0 94392000722
	950272 0 4294967295 3276111872 3276141668 3274440352 3274439976
	3273467584 0 0 4096 90115 3221712796 0 0 17 0 0 0 0

The code boundaries are then 3276111872 to 3276141668, which are:

	(gdb) p/x 3276111872
	$1 = 0xc3458000
	(gdb) p/x 3276141668
	$2 = 0xc345f464

And these correspond to this line in the maps file instead:

	c3458000-c345f464 r-xs 00000000 00:0b 16384612  /usr/sbin/inetd

Which is now correct.

Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>