| Message ID | 20190508071636.13804-1-camann@suse.com |
|---|---|
| State | Accepted |
| Headers | show |
| Series | [v3] crypto/af_alg02: fixed read() being stuck | expand |
On Wed, May 8, 2019 at 3:16 PM Christian Amann <camann@suse.com> wrote: > On kernels < 4.14 (missing commit 2d97591ef43d) reading from > the request socket does not return and the testcase does not > finish. > > This fix moves the logic to a child thread in order for the > parent to handle the timeout and report a message to the user. > > Signed-off-by: Christian Amann <camann@suse.com> > Reviewed-by: Li Wang <liwang@redhat.com> --- > > Notes: > Hi Li, > > > We could set LTP_ATTRIBUTE_UNUSED at the behind of unused parameter > to get > > rid of compiling warning > > Thats very useful but I couldn't find it anywhere in the documentation. > IMHO it should be put in there, because I stumbled upon this problem > a couple of times. > This is just a definition for variable attribute which supports by GNU compiler, I'm not sure if we should add it to LTP documents. $ grep LTP_ATTRIBUTE_UNUSED . -r tst_common.h:25:#define LTP_ATTRIBUTE_UNUSED __attribute__((unused)) > > Anyway, I implemented your suggestions. I hope it's an alright patch > now. > Thanks for your feedback! > > Regards, > Christian > > testcases/kernel/crypto/Makefile | 2 ++ > testcases/kernel/crypto/af_alg02.c | 37 > +++++++++++++++++++++++++++++++++++-- > 2 files changed, 37 insertions(+), 2 deletions(-) > > diff --git a/testcases/kernel/crypto/Makefile > b/testcases/kernel/crypto/Makefile > index 76f9308c2..6547e1cb6 100644 > --- a/testcases/kernel/crypto/Makefile > +++ b/testcases/kernel/crypto/Makefile > @@ -20,3 +20,5 @@ include $(top_srcdir)/include/mk/testcases.mk > CFLAGS += -D_GNU_SOURCE > > include $(top_srcdir)/include/mk/generic_leaf_target.mk > + > +af_alg02: CFLAGS += -pthread > diff --git a/testcases/kernel/crypto/af_alg02.c > b/testcases/kernel/crypto/af_alg02.c > index a9e820423..1c725212a 100644 > --- a/testcases/kernel/crypto/af_alg02.c > +++ b/testcases/kernel/crypto/af_alg02.c > @@ -7,23 +7,56 @@ > * Regression test for commit ecaaab564978 ("crypto: salsa20 - fix > * blkcipher_walk API usage"), or CVE-2017-17805. This test verifies > that an > * empty message can be encrypted with Salsa20 without crashing the > kernel. > + * > + * Fix for kernels < 4.14: > + * With kernels missing commit 2d97591ef43d ("crypto: af_alg - > consolidation > + * of duplicate code") read() does not return in this situation. The call > is > + * now moved to a child thread in order to cancel it in case read() takes > an > + * unusual long amount of time. > */ > > #include "tst_test.h" > #include "tst_af_alg.h" > +#include "tst_safe_pthread.h" > +#include <pthread.h> > +#include <errno.h> > > -static void run(void) > +void *verify_encrypt(void *arg LTP_ATTRIBUTE_UNUSED) > { > char buf[16]; > int reqfd = tst_alg_setup_reqfd("skcipher", "salsa20", NULL, 16); > > + TST_CHECKPOINT_WAKE(0); > + > /* With the bug the kernel crashed here */ > if (read(reqfd, buf, 16) == 0) > tst_res(TPASS, "Successfully \"encrypted\" an empty > message"); > else > - tst_res(TBROK, "read() didn't return 0"); > + tst_res(TFAIL, "read() didn't return 0"); > + return arg; > Since arg has been marked as unused, so here better to return NULL. Anyway, patch V3 looks good to me.
> -static void run(void) > +void *verify_encrypt(void *arg LTP_ATTRIBUTE_UNUSED) > { > char buf[16]; > int reqfd = tst_alg_setup_reqfd("skcipher", "salsa20", NULL, 16); > > + TST_CHECKPOINT_WAKE(0); > + > /* With the bug the kernel crashed here */ > if (read(reqfd, buf, 16) == 0) > tst_res(TPASS, "Successfully \"encrypted\" an empty message"); > else > - tst_res(TBROK, "read() didn't return 0"); > + tst_res(TFAIL, "read() didn't return 0"); > + return arg; Actually there is no point in adding the LTP_ATTRIBUTE_UNUSED since you do return arg; at the end of the function. So I've removed the LTP_ATTRIBUTE_UNUSED, changed the function to be static and pushed. thanks. > +} > + > +static void run(void) > +{ > + pthread_t thr; > + > + pthread_setcancelstate(PTHREAD_CANCEL_ENABLE, NULL); > + SAFE_PTHREAD_CREATE(&thr, NULL, verify_encrypt, NULL); > + > + TST_CHECKPOINT_WAIT(0); > + > + while (pthread_kill(thr, 0) != ESRCH) { > + if (tst_timeout_remaining() <= 10) { > + pthread_cancel(thr); > + tst_brk(TBROK, > + "Timed out while reading from request socket."); > + } > + usleep(1000); > + } > } > > static struct tst_test test = { > .test_all = run, > + .timeout = 20, > + .needs_checkpoints = 1, > }; > -- > 2.16.4 > > > -- > Mailing list info: https://lists.linux.it/listinfo/ltp
diff --git a/testcases/kernel/crypto/Makefile b/testcases/kernel/crypto/Makefile index 76f9308c2..6547e1cb6 100644 --- a/testcases/kernel/crypto/Makefile +++ b/testcases/kernel/crypto/Makefile @@ -20,3 +20,5 @@ include $(top_srcdir)/include/mk/testcases.mk CFLAGS += -D_GNU_SOURCE include $(top_srcdir)/include/mk/generic_leaf_target.mk + +af_alg02: CFLAGS += -pthread diff --git a/testcases/kernel/crypto/af_alg02.c b/testcases/kernel/crypto/af_alg02.c index a9e820423..1c725212a 100644 --- a/testcases/kernel/crypto/af_alg02.c +++ b/testcases/kernel/crypto/af_alg02.c @@ -7,23 +7,56 @@ * Regression test for commit ecaaab564978 ("crypto: salsa20 - fix * blkcipher_walk API usage"), or CVE-2017-17805. This test verifies that an * empty message can be encrypted with Salsa20 without crashing the kernel. + * + * Fix for kernels < 4.14: + * With kernels missing commit 2d97591ef43d ("crypto: af_alg - consolidation + * of duplicate code") read() does not return in this situation. The call is + * now moved to a child thread in order to cancel it in case read() takes an + * unusual long amount of time. */ #include "tst_test.h" #include "tst_af_alg.h" +#include "tst_safe_pthread.h" +#include <pthread.h> +#include <errno.h> -static void run(void) +void *verify_encrypt(void *arg LTP_ATTRIBUTE_UNUSED) { char buf[16]; int reqfd = tst_alg_setup_reqfd("skcipher", "salsa20", NULL, 16); + TST_CHECKPOINT_WAKE(0); + /* With the bug the kernel crashed here */ if (read(reqfd, buf, 16) == 0) tst_res(TPASS, "Successfully \"encrypted\" an empty message"); else - tst_res(TBROK, "read() didn't return 0"); + tst_res(TFAIL, "read() didn't return 0"); + return arg; +} + +static void run(void) +{ + pthread_t thr; + + pthread_setcancelstate(PTHREAD_CANCEL_ENABLE, NULL); + SAFE_PTHREAD_CREATE(&thr, NULL, verify_encrypt, NULL); + + TST_CHECKPOINT_WAIT(0); + + while (pthread_kill(thr, 0) != ESRCH) { + if (tst_timeout_remaining() <= 10) { + pthread_cancel(thr); + tst_brk(TBROK, + "Timed out while reading from request socket."); + } + usleep(1000); + } } static struct tst_test test = { .test_all = run, + .timeout = 20, + .needs_checkpoints = 1, };