On Wed, Oct 2, 2019 at 12:54 AM Eric W. Biederman <ebiederm@xxxxxxxxxxxx> wrote: > Kees Cook <keescook@xxxxxxxxxxxx> writes: > > On Tue, Oct 01, 2019 at 01:36:32PM -0500, Eric W. Biederman wrote: > > > > I think you can actually take this further and remove (or at least > > empty) the uapi/linux/sysctl.h file too. > > I copied everyone who had put this into a defconfig and I will wait a > little more to see if anyone screams. I think it is a safe guess that > several of the affected configurations are dead (or at least > unmaintained) as I received 17 bounces when copying everyone. Looking at the arm defconfigs: > arch/arm/configs/axm55xx_defconfig:CONFIG_SYSCTL_SYSCALL=y No notable work on this platform since it got sold to Intel in 2014. I think they still use it but not with mainline kernels that lack support for most drivers and the later chips. > arch/arm/configs/keystone_defconfig:CONFIG_SYSCTL_SYSCALL=y Not that old either, but this hardware is mostly obsoleted by newer variants that we support with the arm64 defconfig. > arch/arm/configs/lpc32xx_defconfig:CONFIG_SYSCTL_SYSCALL=y > arch/arm/configs/moxart_defconfig:CONFIG_SYSCTL_SYSCALL=y Ancient hardware, but still in active use. These tend to have very little RAM, but they both enable CONFIG_PROC_FS. > arch/arm/configs/qcom_defconfig:CONFIG_SYSCTL_SYSCALL=y > arch/arm/configs/zx_defconfig:CONFIG_SYSCTL_SYSCALL=y These are for older Qualcomm and LG chips that tend to be used with Android rather than the defconfig here. Maybe double-check if the official android-common tree enables SYSCTL_SYSCALL. Arnd