Hi Muhammad
On Fri, Aug 9, 2024 at 1:25 AM Muhammad Usama Anjum
<usama.anjum@xxxxxxxxxxxxx> wrote:
>
> The __NR_mmap isn't found on armhf. The mmap() is commonly available
> system call and its wrapper is presnet on all architectures. So it
> should be used directly. It solves problem for armhf and doesn't create
> problem for architectures as well. Remove sys_mmap() functions as they
> aren't doing anything else other than calling mmap(). There is no need
> to set errno = 0 manually as glibc always resets it.
>
The mseal_test should't have dependency on libc, and mmap() is
implemented by glibc, right ?
I just fixed a bug to switch mremap() to sys_mremap to address an
issue that different glibc version's behavior is slightly different
for mremap().
What is the reason that __NR_mmap not available in armhf ? (maybe it
is another name ?) there must be a way to call syscall directly on
armhf, can we use that instead ?
Thanks
-Jeff
> For reference errors are as following:
>
> CC seal_elf
> seal_elf.c: In function 'sys_mmap':
> seal_elf.c:39:33: error: '__NR_mmap' undeclared (first use in this function)
> 39 | sret = (void *) syscall(__NR_mmap, addr, len, prot,
> | ^~~~~~~~~
>
> mseal_test.c: In function 'sys_mmap':
> mseal_test.c:90:33: error: '__NR_mmap' undeclared (first use in this function)
> 90 | sret = (void *) syscall(__NR_mmap, addr, len, prot,
> | ^~~~~~~~~
>
> Cc: stable@xxxxxxxxxxxxxxx
> Fixes: 4926c7a52de7 ("selftest mm/mseal memory sealing")
> Signed-off-by: Muhammad Usama Anjum <usama.anjum@xxxxxxxxxxxxx>
> ---
> tools/testing/selftests/mm/mseal_test.c | 37 +++++++++----------------
> tools/testing/selftests/mm/seal_elf.c | 13 +--------
> 2 files changed, 14 insertions(+), 36 deletions(-)
>
> diff --git a/tools/testing/selftests/mm/mseal_test.c b/tools/testing/selftests/mm/mseal_test.c
> index a818f010de479..bfcea5cf9a484 100644
> --- a/tools/testing/selftests/mm/mseal_test.c
> +++ b/tools/testing/selftests/mm/mseal_test.c
> @@ -81,17 +81,6 @@ static int sys_mprotect_pkey(void *ptr, size_t size, unsigned long orig_prot,
> return sret;
> }
>
> -static void *sys_mmap(void *addr, unsigned long len, unsigned long prot,
> - unsigned long flags, unsigned long fd, unsigned long offset)
> -{
> - void *sret;
> -
> - errno = 0;
> - sret = (void *) syscall(__NR_mmap, addr, len, prot,
> - flags, fd, offset);
> - return sret;
> -}
> -
> static int sys_munmap(void *ptr, size_t size)
> {
> int sret;
> @@ -172,7 +161,7 @@ static void setup_single_address(int size, void **ptrOut)
> {
> void *ptr;
>
> - ptr = sys_mmap(NULL, size, PROT_READ, MAP_ANONYMOUS | MAP_PRIVATE, -1, 0);
> + ptr = mmap(NULL, size, PROT_READ, MAP_ANONYMOUS | MAP_PRIVATE, -1, 0);
> *ptrOut = ptr;
> }
>
> @@ -181,7 +170,7 @@ static void setup_single_address_rw(int size, void **ptrOut)
> void *ptr;
> unsigned long mapflags = MAP_ANONYMOUS | MAP_PRIVATE;
>
> - ptr = sys_mmap(NULL, size, PROT_READ | PROT_WRITE, mapflags, -1, 0);
> + ptr = mmap(NULL, size, PROT_READ | PROT_WRITE, mapflags, -1, 0);
> *ptrOut = ptr;
> }
>
> @@ -205,7 +194,7 @@ bool seal_support(void)
> void *ptr;
> unsigned long page_size = getpagesize();
>
> - ptr = sys_mmap(NULL, page_size, PROT_READ, MAP_ANONYMOUS | MAP_PRIVATE, -1, 0);
> + ptr = mmap(NULL, page_size, PROT_READ, MAP_ANONYMOUS | MAP_PRIVATE, -1, 0);
> if (ptr == (void *) -1)
> return false;
>
> @@ -481,8 +470,8 @@ static void test_seal_zero_address(void)
> int prot;
>
> /* use mmap to change protection. */
> - ptr = sys_mmap(0, size, PROT_NONE,
> - MAP_ANONYMOUS | MAP_PRIVATE | MAP_FIXED, -1, 0);
> + ptr = mmap(0, size, PROT_NONE,
> + MAP_ANONYMOUS | MAP_PRIVATE | MAP_FIXED, -1, 0);
> FAIL_TEST_IF_FALSE(ptr == 0);
>
> size = get_vma_size(ptr, &prot);
> @@ -1209,8 +1198,8 @@ static void test_seal_mmap_overwrite_prot(bool seal)
> }
>
> /* use mmap to change protection. */
> - ret2 = sys_mmap(ptr, size, PROT_NONE,
> - MAP_ANONYMOUS | MAP_PRIVATE | MAP_FIXED, -1, 0);
> + ret2 = mmap(ptr, size, PROT_NONE,
> + MAP_ANONYMOUS | MAP_PRIVATE | MAP_FIXED, -1, 0);
> if (seal) {
> FAIL_TEST_IF_FALSE(ret2 == MAP_FAILED);
> FAIL_TEST_IF_FALSE(errno == EPERM);
> @@ -1240,8 +1229,8 @@ static void test_seal_mmap_expand(bool seal)
> }
>
> /* use mmap to expand. */
> - ret2 = sys_mmap(ptr, size, PROT_READ,
> - MAP_ANONYMOUS | MAP_PRIVATE | MAP_FIXED, -1, 0);
> + ret2 = mmap(ptr, size, PROT_READ,
> + MAP_ANONYMOUS | MAP_PRIVATE | MAP_FIXED, -1, 0);
> if (seal) {
> FAIL_TEST_IF_FALSE(ret2 == MAP_FAILED);
> FAIL_TEST_IF_FALSE(errno == EPERM);
> @@ -1268,8 +1257,8 @@ static void test_seal_mmap_shrink(bool seal)
> }
>
> /* use mmap to shrink. */
> - ret2 = sys_mmap(ptr, 8 * page_size, PROT_READ,
> - MAP_ANONYMOUS | MAP_PRIVATE | MAP_FIXED, -1, 0);
> + ret2 = mmap(ptr, 8 * page_size, PROT_READ,
> + MAP_ANONYMOUS | MAP_PRIVATE | MAP_FIXED, -1, 0);
> if (seal) {
> FAIL_TEST_IF_FALSE(ret2 == MAP_FAILED);
> FAIL_TEST_IF_FALSE(errno == EPERM);
> @@ -1650,7 +1639,7 @@ static void test_seal_discard_ro_anon_on_filebacked(bool seal)
> ret = fallocate(fd, 0, 0, size);
> FAIL_TEST_IF_FALSE(!ret);
>
> - ptr = sys_mmap(NULL, size, PROT_READ, mapflags, fd, 0);
> + ptr = mmap(NULL, size, PROT_READ, mapflags, fd, 0);
> FAIL_TEST_IF_FALSE(ptr != MAP_FAILED);
>
> if (seal) {
> @@ -1680,7 +1669,7 @@ static void test_seal_discard_ro_anon_on_shared(bool seal)
> int ret;
> unsigned long mapflags = MAP_ANONYMOUS | MAP_SHARED;
>
> - ptr = sys_mmap(NULL, size, PROT_READ, mapflags, -1, 0);
> + ptr = mmap(NULL, size, PROT_READ, mapflags, -1, 0);
> FAIL_TEST_IF_FALSE(ptr != (void *)-1);
>
> if (seal) {
> diff --git a/tools/testing/selftests/mm/seal_elf.c b/tools/testing/selftests/mm/seal_elf.c
> index 7aa1366063e4e..d9f8ba8d5050b 100644
> --- a/tools/testing/selftests/mm/seal_elf.c
> +++ b/tools/testing/selftests/mm/seal_elf.c
> @@ -30,17 +30,6 @@ static int sys_mseal(void *start, size_t len)
> return sret;
> }
>
> -static void *sys_mmap(void *addr, unsigned long len, unsigned long prot,
> - unsigned long flags, unsigned long fd, unsigned long offset)
> -{
> - void *sret;
> -
> - errno = 0;
> - sret = (void *) syscall(__NR_mmap, addr, len, prot,
> - flags, fd, offset);
> - return sret;
> -}
> -
> static inline int sys_mprotect(void *ptr, size_t size, unsigned long prot)
> {
> int sret;
> @@ -56,7 +45,7 @@ static bool seal_support(void)
> void *ptr;
> unsigned long page_size = getpagesize();
>
> - ptr = sys_mmap(NULL, page_size, PROT_READ, MAP_ANONYMOUS | MAP_PRIVATE, -1, 0);
> + ptr = mmap(NULL, page_size, PROT_READ, MAP_ANONYMOUS | MAP_PRIVATE, -1, 0);
> if (ptr == (void *) -1)
> return false;
>
> --
> 2.39.2
>
