* [LTP] [PATCH 1/2] clock_nanosleep01: Avoid dereferencing bad pointers in libc on 32bit
@ 2021-09-29 8:59 Richard Palethorpe via ltp
2021-09-29 8:59 ` [LTP] [PATCH 2/2] clock_nanosleep01: Add space to make make-check happy Richard Palethorpe via ltp
2021-10-04 6:07 ` [LTP] [PATCH 1/2] clock_nanosleep01: Avoid dereferencing bad pointers in libc on 32bit Petr Vorel
0 siblings, 2 replies; 6+ messages in thread
From: Richard Palethorpe via ltp @ 2021-09-29 8:59 UTC (permalink / raw)
To: ltp; +Cc: Richard Palethorpe
In 32-bit (regardless of kernel bits) glibc and musl will usually
dereference the timespec pointers and try to read them. In some cases
this might be avoidable, but they must do it in others.
Passing invalid pointers is undefined in POSIX. In any case, AFAICT
libc would have to catch the signal in order to guarantee EFAULT is
returned.
Signed-off-by: Richard Palethorpe <rpalethorpe@suse.com>
---
Possibly we shouldn't test things like this at all through libc
wrappers.
.../kernel/syscalls/clock_nanosleep/clock_nanosleep01.c | 8 ++++++++
1 file changed, 8 insertions(+)
diff --git a/testcases/kernel/syscalls/clock_nanosleep/clock_nanosleep01.c b/testcases/kernel/syscalls/clock_nanosleep/clock_nanosleep01.c
index 382497918..7dc5a043d 100644
--- a/testcases/kernel/syscalls/clock_nanosleep/clock_nanosleep01.c
+++ b/testcases/kernel/syscalls/clock_nanosleep/clock_nanosleep01.c
@@ -154,6 +154,14 @@ static void do_test(unsigned int i)
else
remain = tst_ts_get(rm);
+ if ((request == bad_addr || remain == bad_addr) &&
+ tv->clock_nanosleep == libc_clock_nanosleep &&
+ sizeof(long) < 8) {
+ tst_res(TCONF,
+ "The libc 32-bit wrapper may dereference req or rem");
+ return;
+ }
+
TEST(tv->clock_nanosleep(tc->clk_id, tc->flags, request, remain));
if (tv->clock_nanosleep == libc_clock_nanosleep) {
--
2.33.0
--
Mailing list info: https://lists.linux.it/listinfo/ltp
^ permalink raw reply related [flat|nested] 6+ messages in thread* [LTP] [PATCH 2/2] clock_nanosleep01: Add space to make make-check happy
2021-09-29 8:59 [LTP] [PATCH 1/2] clock_nanosleep01: Avoid dereferencing bad pointers in libc on 32bit Richard Palethorpe via ltp
@ 2021-09-29 8:59 ` Richard Palethorpe via ltp
2021-10-04 6:07 ` Petr Vorel
2021-10-04 6:07 ` [LTP] [PATCH 1/2] clock_nanosleep01: Avoid dereferencing bad pointers in libc on 32bit Petr Vorel
1 sibling, 1 reply; 6+ messages in thread
From: Richard Palethorpe via ltp @ 2021-09-29 8:59 UTC (permalink / raw)
To: ltp; +Cc: Richard Palethorpe
Signed-off-by: Richard Palethorpe <rpalethorpe@suse.com>
---
testcases/kernel/syscalls/clock_nanosleep/clock_nanosleep01.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/testcases/kernel/syscalls/clock_nanosleep/clock_nanosleep01.c b/testcases/kernel/syscalls/clock_nanosleep/clock_nanosleep01.c
index 7dc5a043d..d7b14fd94 100644
--- a/testcases/kernel/syscalls/clock_nanosleep/clock_nanosleep01.c
+++ b/testcases/kernel/syscalls/clock_nanosleep/clock_nanosleep01.c
@@ -200,7 +200,7 @@ static void do_test(unsigned int i)
}
if (remain_ms > expect_ms) {
- tst_res(TFAIL| TTERRNO,
+ tst_res(TFAIL | TTERRNO,
"remaining time > requested time (%lld > %lld)",
remain_ms, expect_ms);
return;
--
2.33.0
--
Mailing list info: https://lists.linux.it/listinfo/ltp
^ permalink raw reply related [flat|nested] 6+ messages in thread* Re: [LTP] [PATCH 1/2] clock_nanosleep01: Avoid dereferencing bad pointers in libc on 32bit
2021-09-29 8:59 [LTP] [PATCH 1/2] clock_nanosleep01: Avoid dereferencing bad pointers in libc on 32bit Richard Palethorpe via ltp
2021-09-29 8:59 ` [LTP] [PATCH 2/2] clock_nanosleep01: Add space to make make-check happy Richard Palethorpe via ltp
@ 2021-10-04 6:07 ` Petr Vorel
2021-10-04 10:16 ` Jan Stancek
1 sibling, 1 reply; 6+ messages in thread
From: Petr Vorel @ 2021-10-04 6:07 UTC (permalink / raw)
To: Richard Palethorpe; +Cc: ltp
Hi Richie,
> In 32-bit (regardless of kernel bits) glibc and musl will usually
> dereference the timespec pointers and try to read them. In some cases
> this might be avoidable, but they must do it in others.
> Passing invalid pointers is undefined in POSIX. In any case, AFAICT
> libc would have to catch the signal in order to guarantee EFAULT is
> returned.
LGTM.
Reviewed-by: Petr Vorel <pvorel@suse.cz>
> Possibly we shouldn't test things like this at all through libc
> wrappers.
Only for 32bit or also for 64 bit? Anyway, there has always been some cases
where bad addr testing was problematic (e.g. non-intel arch).
Kind regards,
Petr
--
Mailing list info: https://lists.linux.it/listinfo/ltp
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [LTP] [PATCH 1/2] clock_nanosleep01: Avoid dereferencing bad pointers in libc on 32bit
2021-10-04 6:07 ` [LTP] [PATCH 1/2] clock_nanosleep01: Avoid dereferencing bad pointers in libc on 32bit Petr Vorel
@ 2021-10-04 10:16 ` Jan Stancek
2021-10-05 12:04 ` Richard Palethorpe
0 siblings, 1 reply; 6+ messages in thread
From: Jan Stancek @ 2021-10-04 10:16 UTC (permalink / raw)
To: Petr Vorel; +Cc: Richard Palethorpe, LTP List
[-- Attachment #1.1: Type: text/plain, Size: 942 bytes --]
On Mon, Oct 4, 2021 at 8:07 AM Petr Vorel <pvorel@suse.cz> wrote:
> Hi Richie,
>
> > In 32-bit (regardless of kernel bits) glibc and musl will usually
> > dereference the timespec pointers and try to read them. In some cases
> > this might be avoidable, but they must do it in others.
>
> > Passing invalid pointers is undefined in POSIX. In any case, AFAICT
> > libc would have to catch the signal in order to guarantee EFAULT is
> > returned.
>
> LGTM.
>
> Reviewed-by: Petr Vorel <pvorel@suse.cz>
>
> > Possibly we shouldn't test things like this at all through libc
> > wrappers.
> Only for 32bit or also for 64 bit? Anyway, there has always been some cases
> where bad addr testing was problematic (e.g. non-intel arch).
>
I'd skip it for both, I recall that some implementations
were crashing.
Acked-by: Jan Stancek <jstancek@redhat.com>
>
> Kind regards,
> Petr
>
> --
> Mailing list info: https://lists.linux.it/listinfo/ltp
>
>
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--
Mailing list info: https://lists.linux.it/listinfo/ltp
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [LTP] [PATCH 1/2] clock_nanosleep01: Avoid dereferencing bad pointers in libc on 32bit
2021-10-04 10:16 ` Jan Stancek
@ 2021-10-05 12:04 ` Richard Palethorpe
0 siblings, 0 replies; 6+ messages in thread
From: Richard Palethorpe @ 2021-10-05 12:04 UTC (permalink / raw)
To: Jan Stancek; +Cc: LTP List
Hello Jan,
Jan Stancek <jstancek@redhat.com> writes:
> On Mon, Oct 4, 2021 at 8:07 AM Petr Vorel <pvorel@suse.cz> wrote:
>
> Hi Richie,
>
> > In 32-bit (regardless of kernel bits) glibc and musl will usually
> > dereference the timespec pointers and try to read them. In some cases
> > this might be avoidable, but they must do it in others.
>
> > Passing invalid pointers is undefined in POSIX. In any case, AFAICT
> > libc would have to catch the signal in order to guarantee EFAULT is
> > returned.
>
> LGTM.
>
> Reviewed-by: Petr Vorel <pvorel@suse.cz>
>
> > Possibly we shouldn't test things like this at all through libc
> > wrappers.
> Only for 32bit or also for 64 bit? Anyway, there has always been some cases
> where bad addr testing was problematic (e.g. non-intel arch).
>
> I'd skip it for both, I recall that some implementations
> were crashing.
Yes, there is not much we can do if it fails.
>
> Acked-by: Jan Stancek <jstancek@redhat.com>
>
>
> Kind regards,
> Petr
>
> --
> Mailing list info: https://lists.linux.it/listinfo/ltp
--
Thank you,
Richard.
--
Mailing list info: https://lists.linux.it/listinfo/ltp
^ permalink raw reply [flat|nested] 6+ messages in thread
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2021-09-29 8:59 [LTP] [PATCH 1/2] clock_nanosleep01: Avoid dereferencing bad pointers in libc on 32bit Richard Palethorpe via ltp
2021-09-29 8:59 ` [LTP] [PATCH 2/2] clock_nanosleep01: Add space to make make-check happy Richard Palethorpe via ltp
2021-10-04 6:07 ` Petr Vorel
2021-10-04 6:07 ` [LTP] [PATCH 1/2] clock_nanosleep01: Avoid dereferencing bad pointers in libc on 32bit Petr Vorel
2021-10-04 10:16 ` Jan Stancek
2021-10-05 12:04 ` Richard Palethorpe
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