| Message ID | 20210508061252.18337-1-liwang@redhat.com |
|---|---|
| State | Accepted |
| Headers | show |
| Series | syscall: remove PROT_WRITE|PROT_EXEC from brk02 | expand |
Reviewed-by: Liam R. Howlett <Liam.Howlett@Oracle.com> * Li Wang <liwang@redhat.com> [210508 02:13]: > We got permission denied while performing the brk02 on x86_64/s390x > (kernel-4.18). After looking at the manual page of mprotect(), seems > the access issue caused by PROT_EXEC. > > " POSIX says that the behavior of mprotect() is unspecified if it is > applied to a region of memory that was not obtained via mmap(2). " > > # ./brk02 > tst_test.c:1291: TINFO: Timeout per run is 0h 05m 00s > brk02.c:41: TFAIL: Cannot mprotect new VMA > > From Liam Howlett: > Just removing the PROT_EXEC invalidates the test. However, if both > PROT_EXEC and PROT_WRITE are removed, then the test still does what > is intended. > > So let's remove 'PROT_WRITE|PROT_EXEC' to make brk02 PASS with > all platforms. > > Suggested-by: Liam Howlett <liam.howlett@oracle.com> > Signed-off-by: Li Wang <liwang@redhat.com> > Cc: Cyril Hrubis <chrubis@suse.cz> > --- > testcases/kernel/syscalls/brk/brk02.c | 3 +-- > 1 file changed, 1 insertion(+), 2 deletions(-) > > diff --git a/testcases/kernel/syscalls/brk/brk02.c b/testcases/kernel/syscalls/brk/brk02.c > index 4a272bac3..11e803cb4 100644 > --- a/testcases/kernel/syscalls/brk/brk02.c > +++ b/testcases/kernel/syscalls/brk/brk02.c > @@ -36,8 +36,7 @@ void brk_down_vmas(void) > return; > } > > - if (mprotect(addr - page_size, page_size, > - PROT_READ|PROT_WRITE|PROT_EXEC)) { > + if (mprotect(addr - page_size, page_size, PROT_READ)) { > tst_res(TFAIL | TERRNO, "Cannot mprotect new VMA"); > return; > } > -- > 2.30.2 >
Liam Howlett <liam.howlett@oracle.com> wrote:
> Reviewed-by: Liam R. Howlett <Liam.Howlett@Oracle.com>
Thanks for the review! Patch applied.
diff --git a/testcases/kernel/syscalls/brk/brk02.c b/testcases/kernel/syscalls/brk/brk02.c index 4a272bac3..11e803cb4 100644 --- a/testcases/kernel/syscalls/brk/brk02.c +++ b/testcases/kernel/syscalls/brk/brk02.c @@ -36,8 +36,7 @@ void brk_down_vmas(void) return; } - if (mprotect(addr - page_size, page_size, - PROT_READ|PROT_WRITE|PROT_EXEC)) { + if (mprotect(addr - page_size, page_size, PROT_READ)) { tst_res(TFAIL | TERRNO, "Cannot mprotect new VMA"); return; }
We got permission denied while performing the brk02 on x86_64/s390x (kernel-4.18). After looking at the manual page of mprotect(), seems the access issue caused by PROT_EXEC. " POSIX says that the behavior of mprotect() is unspecified if it is applied to a region of memory that was not obtained via mmap(2). " # ./brk02 tst_test.c:1291: TINFO: Timeout per run is 0h 05m 00s brk02.c:41: TFAIL: Cannot mprotect new VMA From Liam Howlett: Just removing the PROT_EXEC invalidates the test. However, if both PROT_EXEC and PROT_WRITE are removed, then the test still does what is intended. So let's remove 'PROT_WRITE|PROT_EXEC' to make brk02 PASS with all platforms. Suggested-by: Liam Howlett <liam.howlett@oracle.com> Signed-off-by: Li Wang <liwang@redhat.com> Cc: Cyril Hrubis <chrubis@suse.cz> --- testcases/kernel/syscalls/brk/brk02.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-)