On Wed, 28 Oct 2020 at 00:49, damian damian.tometzki@familie-tometzki.de wrote:

On Mo, 26. Okt 18:03, Jens Axboe wrote:

...

The removal of compat_process_vm_{readv,writev} didn't change process_vm_rw(), which always assumes it's not doing a compat syscall. Instead of passing in 'false' unconditionally for 'compat', make it conditional on in_compat_syscall().

Fixes: c3973b401ef2 ("mm: remove compat_process_vm_{readv,writev}") Reported-by: Kyle Huey me@kylehuey.com Signed-off-by: Jens Axboe axboe@kernel.dk

---

diff --git a/mm/process_vm_access.c b/mm/process_vm_access.c index fd12da80b6f2..05676722d9cd 100644 --- a/mm/process_vm_access.c +++ b/mm/process_vm_access.c @@ -273,7 +273,8 @@ static ssize_t process_vm_rw(pid_t pid, return rc; if (!iov_iter_count(&iter)) goto free_iov_l;

• iov_r = iovec_from_user(rvec, riovcnt, UIO_FASTIOV, iovstack_r, false);
  

• iov_r = iovec_from_user(rvec, riovcnt, UIO_FASTIOV, iovstack_r,
  

•                         in_compat_syscall());
  if (IS_ERR(iov_r)) {
          rc = PTR_ERR(iov_r);
          goto free_iov_l;
  
  

-- Jens Axboe

Hello Jens,

i got the following error when i try to build.

m/process_vm_access.c: In Funktion »process_vm_rw«: mm/process_vm_access.c:277:5: Fehler: Implizite Deklaration der Funktion »in_compat_syscall«; meinten Sie »in_ia32_syscall«? [-Werror=implicit-function-declaration] 277 | in_compat_syscall()); | ^~~~~~~~~~~~~~~~~ | in_ia32_syscall

I have also noticed this build failure on Linus's mainline master branch.

x86_64 : FAILED i386: FAILED arm: FAILED

make -sk KBUILD_BUILD_USER=TuxBuild -C/linux -j16 ARCH=x86 HOSTCC=gcc CC="sccache gcc" O=build

50../mm/process_vm_access.c: In function ‘process_vm_rw’: 51../mm/process_vm_access.c:277:5: error: implicit declaration of function ‘in_compat_syscall’; did you mean ‘in_ia32_syscall’? [-Werror=implicit-function-declaration] 52 277 | in_compat_syscall()); 53 | ^~~~~~~~~~~~~~~~~ 54 | in_ia32_syscall 55cc1: some warnings being treated as errors

Reported-by: Naresh Kamboju naresh.kamboju@linaro.org

full test build log: https://gitlab.com/Linaro/lkft/mirrors/torvalds/linux-mainline/-/jobs/815202...