kernel/git/stable/linux.git/arch/powerpc, branch linux-5.6.y

powerpc/ptdump: Properly handle non standard page size

2020-06-17T14:41:55+00:00

commit b00ff6d8c1c3898b0f768cbb38ef722d25bd2f39 upstream. In order to properly display information regardless of the page size, it is necessary to take into account real page size. Fixes: cabe8138b23c ("powerpc: dump as a single line areas mapping a single physical page.") Cc: stable@vger.kernel.org Signed-off-by: Christophe Leroy Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/a53b2a0ffd042a8d85464bf90d55bc5b970e00a1.1589866984.git.christophe.leroy@csgroup.eu Signed-off-by: Greg Kroah-Hartman

powerpc/xive: Clear the page tables for the ESB IO mapping

2020-06-17T14:41:51+00:00

[ Upstream commit a101950fcb78b0ba20cd487be6627dea58d55c2b ] Commit 1ca3dec2b2df ("powerpc/xive: Prevent page fault issues in the machine crash handler") fixed an issue in the FW assisted dump of machines using hash MMU and the XIVE interrupt mode under the POWER hypervisor. It forced the mapping of the ESB page of interrupts being mapped in the Linux IRQ number space to make sure the 'crash kexec' sequence worked during such an event. But it didn't handle the un-mapping. This mapping is now blocking the removal of a passthrough IO adapter under the POWER hypervisor because it expects the guest OS to have cleared all page table entries related to the adapter. If some are still present, the RTAS call which isolates the PCI slot returns error 9001 "valid outstanding translations". Remove these mapping in the IRQ data cleanup routine. Under KVM, this cleanup is not required because the ESB pages for the adapter interrupts are un-mapped from the guest by the hypervisor in the KVM XIVE native device. This is now redundant but it's harmless. Fixes: 1ca3dec2b2df ("powerpc/xive: Prevent page fault issues in the machine crash handler") Cc: stable@vger.kernel.org # v5.5+ Signed-off-by: Cédric Le Goater Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20200429075122.1216388-2-clg@kaod.org Signed-off-by: Sasha Levin

bpf: Support llvm-objcopy for vmlinux BTF

2020-06-17T14:41:49+00:00

commit 90ceddcb495008ac8ba7a3dce297841efcd7d584 upstream. Simplify gen_btf logic to make it work with llvm-objcopy. The existing 'file format' and 'architecture' parsing logic is brittle and does not work with llvm-objcopy/llvm-objdump. 'file format' output of llvm-objdump>=11 will match GNU objdump, but 'architecture' (bfdarch) may not. .BTF in .tmp_vmlinux.btf is non-SHF_ALLOC. Add the SHF_ALLOC flag because it is part of vmlinux image used for introspection. C code can reference the section via linker script defined __start_BTF and __stop_BTF. This fixes a small problem that previous .BTF had the SHF_WRITE flag (objcopy -I binary -O elf* synthesized .data). Additionally, `objcopy -I binary` synthesized symbols _binary__btf_vmlinux_bin_start and _binary__btf_vmlinux_bin_stop (not used elsewhere) are replaced with more commonplace __start_BTF and __stop_BTF. Add 2>/dev/null because GNU objcopy (but not llvm-objcopy) warns "empty loadable segment detected at vaddr=0xffffffff81000000, is this intentional?" We use a dd command to change the e_type field in the ELF header from ET_EXEC to ET_REL so that lld will accept .btf.vmlinux.bin.o. Accepting ET_EXEC as an input file is an extremely rare GNU ld feature that lld does not intend to support, because this is error-prone. The output section description .BTF in include/asm-generic/vmlinux.lds.h avoids potential subtle orphan section placement issues and suppresses --orphan-handling=warn warnings. Fixes: df786c9b9476 ("bpf: Force .BTF section start to zero when dumping from vmlinux") Fixes: cb0cc635c7a9 ("powerpc: Include .BTF section") Reported-by: Nathan Chancellor Signed-off-by: Fangrui Song Signed-off-by: Daniel Borkmann Tested-by: Stanislav Fomichev Tested-by: Andrii Nakryiko Reviewed-by: Stanislav Fomichev Reviewed-by: Kees Cook Acked-by: Andrii Nakryiko Acked-by: Michael Ellerman (powerpc) Link: https://github.com/ClangBuiltLinux/linux/issues/871 Link: https://lore.kernel.org/bpf/20200318222746.173648-1-maskray@google.com Signed-off-by: Maria Teguiani Signed-off-by: Greg Kroah-Hartman

powerpc/bpf: Enable bpf_probe_read{, str}() on powerpc again

2020-06-03T06:23:37+00:00

commit d195b1d1d1196681ac4775e0361e9cca70f740c2 upstream. The commit 0ebeea8ca8a4d1d453a ("bpf: Restrict bpf_probe_read{, str}() only to archs where they work") caused that bpf_probe_read{, str}() functions were not longer available on architectures where the same logical address might have different content in kernel and user memory mapping. These architectures should use probe_read_{user,kernel}_str helpers. For backward compatibility, the problematic functions are still available on architectures where the user and kernel address spaces are not overlapping. This is defined CONFIG_ARCH_HAS_NON_OVERLAPPING_ADDRESS_SPACE. At the moment, these backward compatible functions are enabled only on x86_64, arm, and arm64. Let's do it also on powerpc that has the non overlapping address space as well. Fixes: 0ebeea8ca8a4 ("bpf: Restrict bpf_probe_read{, str}() only to archs where they work") Signed-off-by: Petr Mladek Signed-off-by: Daniel Borkmann Acked-by: Michael Ellerman Link: https://lore.kernel.org/lkml/20200527122844.19524-1-pmladek@suse.com Signed-off-by: Greg Kroah-Hartman

powerpc/64s: Disable STRICT_KERNEL_RWX

2020-05-27T15:48:17+00:00

commit 8659a0e0efdd975c73355dbc033f79ba3b31e82c upstream. Several strange crashes have been eventually traced back to STRICT_KERNEL_RWX and its interaction with code patching. Various paths in our ftrace, kprobes and other patching code need to be hardened against patching failures, otherwise we can end up running with partially/incorrectly patched ftrace paths, kprobes or jump labels, which can then cause strange crashes. Although fixes for those are in development, they're not -rc material. There also seem to be problems with the underlying strict RWX logic, which needs further debugging. So for now disable STRICT_KERNEL_RWX on 64-bit to prevent people from enabling the option and tripping over the bugs. Fixes: 1e0fc9d1eb2b ("powerpc/Kconfig: Enable STRICT_KERNEL_RWX for some configs") Cc: stable@vger.kernel.org # v4.13+ Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20200520133605.972649-1-mpe@ellerman.id.au Signed-off-by: Greg Kroah-Hartman

powerpc/ima: Fix secure boot rules in ima arch policy

2020-05-20T06:22:36+00:00

commit fa4f3f56ccd28ac031ab275e673ed4098855fed4 upstream. To prevent verifying the kernel module appended signature twice (finit_module), once by the module_sig_check() and again by IMA, powerpc secure boot rules define an IMA architecture specific policy rule only if CONFIG_MODULE_SIG_FORCE is not enabled. This, unfortunately, does not take into account the ability of enabling "sig_enforce" on the boot command line (module.sig_enforce=1). Including the IMA module appraise rule results in failing the finit_module syscall, unless the module signing public key is loaded onto the IMA keyring. This patch fixes secure boot policy rules to be based on CONFIG_MODULE_SIG instead. Fixes: 4238fad366a6 ("powerpc/ima: Add support to initialize ima policy rules") Signed-off-by: Nayna Jain Signed-off-by: Michael Ellerman Signed-off-by: Mimi Zohar Link: https://lore.kernel.org/r/1588342612-14532-1-git-send-email-nayna@linux.ibm.com Signed-off-by: Greg Kroah-Hartman

powerpc/uaccess: Evaluate macro arguments once, before user access is allowed

2020-05-20T06:22:36+00:00

commit d02f6b7dab8228487268298ea1f21081c0b4b3eb upstream. get/put_user() can be called with nontrivial arguments. fs/proc/page.c has a good example: if (put_user(stable_page_flags(ppage), out)) { stable_page_flags() is quite a lot of code, including spin locks in the page allocator. Ensure these arguments are evaluated before user access is allowed. This improves security by reducing code with access to userspace, but it also fixes a PREEMPT bug with KUAP on powerpc/64s: stable_page_flags() is currently called with AMR set to allow writes, it ends up calling spin_unlock(), which can call preempt_schedule. But the task switch code can not be called with AMR set (it relies on interrupts saving the register), so this blows up. It's fine if the code inside allow_user_access() is preemptible, because a timer or IPI will save the AMR, but it's not okay to explicitly cause a reschedule. Fixes: de78a9c42a79 ("powerpc: Add a framework for Kernel Userspace Access Protection") Signed-off-by: Nicholas Piggin Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20200407041245.600651-1-npiggin@gmail.com Signed-off-by: Greg Kroah-Hartman

powerpc/32s: Fix build failure with CONFIG_PPC_KUAP_DEBUG

2020-05-20T06:22:30+00:00

commit 4833ce06e6855d526234618b746ffb71d6612c9a upstream. gpr2 is not a parametre of kuap_check(), it doesn't exist. Use gpr instead. Fixes: a68c31fc01ef ("powerpc/32s: Implement Kernel Userspace Access Protection") Signed-off-by: Christophe Leroy Signed-off-by: Michael Ellerman Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/ea599546f2a7771bde551393889e44e6b2632332.1587368807.git.christophe.leroy@c-s.fr Signed-off-by: Greg Kroah-Hartman

powerpc/vdso32: Fallback on getres syscall when clock is unknown

2020-05-20T06:22:29+00:00

commit e963b7a28b2bf2416304e1a15df967fcf662aff5 upstream. There are other clocks than the standard ones, for instance per process clocks. Therefore, being above the last standard clock doesn't mean it is a bad clock. So, fallback to syscall instead of returning -EINVAL inconditionaly. Fixes: e33ffc956b08 ("powerpc/vdso32: implement clock_getres entirely") Cc: stable@vger.kernel.org # v5.6+ Reported-by: Aurelien Jarno Signed-off-by: Christophe Leroy Signed-off-by: Michael Ellerman Tested-by: Aurelien Jarno Link: https://lore.kernel.org/r/7316a9e2c0c2517923eb4b0411c4a08d15e675a4.1589017281.git.christophe.leroy@csgroup.eu Signed-off-by: Greg Kroah-Hartman

powerpc/mm: Fix CONFIG_PPC_KUAP_DEBUG on PPC32

2020-04-29T14:34:57+00:00

commit feb8e960d780e170e992a70491eec9dd68f4dbf2 upstream. CONFIG_PPC_KUAP_DEBUG is not selectable because it depends on PPC_32 which doesn't exists. Fixing it leads to a deadlock due to a vital register getting clobbered in _switch(). Change dependency to PPC32 and use r0 instead of r4 in _switch() Fixes: e2fb9f544431 ("powerpc/32: Prepare for Kernel Userspace Access Protection") Cc: stable@vger.kernel.org # v5.2+ Signed-off-by: Christophe Leroy Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/540242f7d4573f7cdf1b3bf46bb35f743b2cd68f.1587124651.git.christophe.leroy@c-s.fr Signed-off-by: Greg Kroah-Hartman