This is a note to let you know that I've just added the patch titled
[PATCH stable v4.14 04/32] powerpc: Use barrier_nospec in copy_from_user() to the 4.14-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: powerpc-use-barrier_nospec-in-copy_from_user.patch and it can be found in the queue-4.14 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <sta...@vger.kernel.org> know about it. >From foo@baz Fri Mar 29 15:53:50 CET 2019 From: Michael Ellerman <m...@ellerman.id.au> Date: Fri, 29 Mar 2019 22:25:52 +1100 Subject: [PATCH stable v4.14 04/32] powerpc: Use barrier_nospec in copy_from_user() To: sta...@vger.kernel.org, gre...@linuxfoundation.org Cc: linuxppc-...@ozlabs.org, diana.crac...@nxp.com, msucha...@suse.de, christophe.le...@c-s.fr Message-ID: <20190329112620.14489-5-...@ellerman.id.au> From: Michael Ellerman <m...@ellerman.id.au> commit ddf35cf3764b5a182b178105f57515b42e2634f8 upstream. Based on the x86 commit doing the same. See commit 304ec1b05031 ("x86/uaccess: Use __uaccess_begin_nospec() and uaccess_try_nospec") and b3bbfb3fb5d2 ("x86: Introduce __uaccess_begin_nospec() and uaccess_try_nospec") for more detail. In all cases we are ordering the load from the potentially user-controlled pointer vs a previous branch based on an access_ok() check or similar. Base on a patch from Michal Suchanek. Signed-off-by: Michal Suchanek <msucha...@suse.de> Signed-off-by: Michael Ellerman <m...@ellerman.id.au> Signed-off-by: Greg Kroah-Hartman <gre...@linuxfoundation.org> --- arch/powerpc/include/asm/uaccess.h | 11 ++++++++++- 1 file changed, 10 insertions(+), 1 deletion(-) --- a/arch/powerpc/include/asm/uaccess.h +++ b/arch/powerpc/include/asm/uaccess.h @@ -238,6 +238,7 @@ do { \ __chk_user_ptr(ptr); \ if (!is_kernel_addr((unsigned long)__gu_addr)) \ might_fault(); \ + barrier_nospec(); \ __get_user_size(__gu_val, __gu_addr, (size), __gu_err); \ (x) = (__typeof__(*(ptr)))__gu_val; \ __gu_err; \ @@ -249,8 +250,10 @@ do { \ __long_type(*(ptr)) __gu_val = 0; \ const __typeof__(*(ptr)) __user *__gu_addr = (ptr); \ might_fault(); \ - if (access_ok(VERIFY_READ, __gu_addr, (size))) \ + if (access_ok(VERIFY_READ, __gu_addr, (size))) { \ + barrier_nospec(); \ __get_user_size(__gu_val, __gu_addr, (size), __gu_err); \ + } \ (x) = (__force __typeof__(*(ptr)))__gu_val; \ __gu_err; \ }) @@ -261,6 +264,7 @@ do { \ __long_type(*(ptr)) __gu_val; \ const __typeof__(*(ptr)) __user *__gu_addr = (ptr); \ __chk_user_ptr(ptr); \ + barrier_nospec(); \ __get_user_size(__gu_val, __gu_addr, (size), __gu_err); \ (x) = (__force __typeof__(*(ptr)))__gu_val; \ __gu_err; \ @@ -288,15 +292,19 @@ static inline unsigned long raw_copy_fro switch (n) { case 1: + barrier_nospec(); __get_user_size(*(u8 *)to, from, 1, ret); break; case 2: + barrier_nospec(); __get_user_size(*(u16 *)to, from, 2, ret); break; case 4: + barrier_nospec(); __get_user_size(*(u32 *)to, from, 4, ret); break; case 8: + barrier_nospec(); __get_user_size(*(u64 *)to, from, 8, ret); break; } @@ -304,6 +312,7 @@ static inline unsigned long raw_copy_fro return 0; } + barrier_nospec(); return __copy_tofrom_user((__force void __user *)to, from, n); } Patches currently in stable-queue which might be from m...@ellerman.id.au are queue-4.14/powerpc-fsl-emulate-sprn_bucsr-register.patch queue-4.14/powerpc-64-make-stf-barrier-ppc_book3s_64-specific.patch queue-4.14/powerpc-fsl-fix-spectre_v2-mitigations-reporting.patch queue-4.14/powerpc-64s-patch-barrier_nospec-in-modules.patch queue-4.14/powerpc-pseries-query-hypervisor-for-count-cache-flush-settings.patch queue-4.14/powerpc-64s-add-support-for-software-count-cache-flush.patch queue-4.14/powerpc64s-show-ori31-availability-in-spectre_v1-sysfs-file-not-v2.patch queue-4.14/powerpc-fsl-flush-the-branch-predictor-at-each-kernel-entry-64bit.patch queue-4.14/powerpc-fsl-update-spectre-v2-reporting.patch queue-4.14/powerpc-64-make-meltdown-reporting-book3s-64-specific.patch queue-4.14/powerpc-64s-add-support-for-ori-barrier_nospec-patching.patch queue-4.14/powerpc-use-barrier_nospec-in-copy_from_user.patch queue-4.14/powerpc-fsl-sanitize-the-syscall-table-for-nxp-powerpc-32-bit-platforms.patch queue-4.14/powerpc-fsl-add-macro-to-flush-the-branch-predictor.patch queue-4.14/powerpc-fsl-add-barrier_nospec-implementation-for-nxp-powerpc-book3e.patch queue-4.14/powerpc-security-fix-spectre_v2-reporting.patch queue-4.14/powerpc-64-disable-the-speculation-barrier-from-the-command-line.patch queue-4.14/powerpc-fsl-fix-the-flush-of-branch-predictor.patch queue-4.14/powerpc-64-add-config_ppc_barrier_nospec.patch queue-4.14/powerpc-fsl-enable-runtime-patching-if-nospectre_v2-boot-arg-is-used.patch queue-4.14/powerpc-64-use-barrier_nospec-in-syscall-entry.patch queue-4.14/powerpc-fsl-fixed-warning-orphan-section-__btb_flush_fixup.patch queue-4.14/powerpc-fsl-add-nospectre_v2-command-line-argument.patch queue-4.14/powerpc-64s-add-new-security-feature-flags-for-count-cache-flush.patch queue-4.14/powerpc-fsl-add-infrastructure-to-fixup-branch-predictor-flush.patch queue-4.14/powerpc-64s-enhance-the-information-in-cpu_show_spectre_v1.patch queue-4.14/powerpc-64-call-setup_barrier_nospec-from-setup_arch.patch queue-4.14/powerpc-asm-add-a-patch_site-macro-helpers-for-patching-instructions.patch queue-4.14/powerpc-fsl-flush-the-branch-predictor-at-each-kernel-entry-32-bit.patch queue-4.14/powerpc-64s-enable-barrier_nospec-based-on-firmware-settings.patch queue-4.14/powerpc-fsl-flush-branch-predictor-when-entering-kvm.patch queue-4.14/powerpc-powernv-query-firmware-for-count-cache-flush-settings.patch