On Mon, Jun 14, 2021 at 6:55 PM youling 257 <youling257@xxxxxxxxx> wrote: > > if try to find problem on userspace, i used linux 5.13rc6 on old > android 7 cm14.1, not aosp android 11. > http://git.osdn.net/view?p=android-x86/system-core.git;a=blob;f=init/service.cpp;h=a5334f447fc2fc34453d2f6a37523bedccadc690;hb=refs/heads/cm-14.1-x86#l457 > > 457 if (!seclabel_.empty()) { > 458 if (setexeccon(seclabel_.c_str()) < 0) { > 459 ERROR("cannot setexeccon('%s'): %s\n", > 460 seclabel_.c_str(), strerror(errno)); > 461 _exit(127); > 462 } > 463 } I have no idea where the cm14.1 libraries are. Does anybody know where the matching source code for setexeccon() would be? For me - obviously not on cm14.1 - all "setexeccon()" does is n = openat(AT_FDCWD, "/proc/thread-self/attr/exec", O_RDWR|O_CLOEXEC) write(n, string, len) close(n) and if that fails, it would seem to indicate that proc_mem_open() failed. Which would be mm_access() failing. But I don't see how that can be the case, because mm_access() explicitly allows "mm == current->mm" (which the above clearly should be). youling, can you double-check with the current -git tree? But as far as I can tell, my minimal patch is exactly the same as Kees' patch (just smaller and simpler). Kees, do you see anything? Linus