Messages in this thread | | | Date | Sun, 6 Feb 2005 13:45:23 +0100 | From | Ingo Molnar <> | Subject | Re: [PROPOSAL/PATCH] Remove PT_GNU_STACK support before 2.6.11 |
| |
* Ingo Molnar <mingo@elte.hu> wrote:
> * Arjan van de Ven <arjan@infradead.org> wrote: > > > So I rather see the patch below merged instead; it fixes the worst > > problems (RWE not marking the heap executable) while keeping this > > useful feature enabled. > > > > Signed-off-by: Arjan van de Ven <arjan@infradead.org> > > looks good. > > Signed-off-by: Ingo Molnar <mingo@elte.hu>
tested it against BK-curr, on an NX-enabled x86 CPU, and it builds/boots fine and works as expected. A PT_GNU_STACK RWE binary gets this layout:
saturn:~/noexec> cat /proc/2983/maps 00888000-0089d000 r-xp 00000000 03:41 3433999 /lib/ld-2.3.3.so 0089d000-0089f000 rwxp 00014000 03:41 3433999 /lib/ld-2.3.3.so 008a1000-009bf000 r-xp 00000000 03:41 3434007 /lib/tls/libc-2.3.3.so 009bf000-009c1000 r-xp 0011d000 03:41 3434007 /lib/tls/libc-2.3.3.so 009c1000-009c3000 rwxp 0011f000 03:41 3434007 /lib/tls/libc-2.3.3.so 009c3000-009c5000 rwxp 009c3000 00:00 0 08048000-08049000 r-xp 00000000 03:41 1046974 /home/mingo/noexec/test-stack 08049000-0804a000 rwxp 00000000 03:41 1046974 /home/mingo/noexec/test-stack b7fe7000-b7fe8000 rwxp b7fe7000 00:00 0 bffeb000-c0000000 rwxp bffeb000 00:00 0 ffffe000-fffff000 ---p 00000000 00:00 0
i.e. all mappings are executable (i.e. READ_IMPLIES_EXEC effect) - the intended change. (although i dont fully agree with PT_GNU_STACK being about something else than the stack, from a security POV if the stack is executable then all bets are off anyway. The heap and all mmaps being executable too in that case makes little difference.)
Ingo - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
| |