[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>
1 file changed