From 39e71d5ae83f83dfd42f44c84ed49136c497fb14 Mon Sep 17 00:00:00 2001 From: Michal Suchanek Date: Mon, 22 Apr 2019 00:20:12 +1000 Subject: [PATCH] powerpc/64s: Patch barrier_nospec in modules commit 815069ca57c142eb71d27439bc27f41a433a67b3 upstream. Note that unlike RFI which is patched only in kernel the nospec state reflects settings at the time the module was loaded. Iterating all modules and re-patching every time the settings change is not implemented. Based on lwsync patching. Signed-off-by: Michal Suchanek Signed-off-by: Michael Ellerman Signed-off-by: Greg Kroah-Hartman --- arch/powerpc/include/asm/setup.h | 7 +++++++ arch/powerpc/kernel/module.c | 6 ++++++ arch/powerpc/kernel/security.c | 2 +- arch/powerpc/lib/feature-fixups.c | 16 +++++++++++++--- 4 files changed, 27 insertions(+), 4 deletions(-) diff --git a/arch/powerpc/include/asm/setup.h b/arch/powerpc/include/asm/setup.h index 80c35275bbdb..fed0b352e24f 100644 --- a/arch/powerpc/include/asm/setup.h +++ b/arch/powerpc/include/asm/setup.h @@ -39,6 +39,13 @@ enum l1d_flush_type { void setup_rfi_flush(enum l1d_flush_type, bool enable); void do_rfi_flush_fixups(enum l1d_flush_type types); void do_barrier_nospec_fixups(bool enable); +extern bool barrier_nospec_enabled; + +#ifdef CONFIG_PPC_BOOK3S_64 +void do_barrier_nospec_fixups_range(bool enable, void *start, void *end); +#else +static inline void do_barrier_nospec_fixups_range(bool enable, void *start, void *end) { }; +#endif #endif /* !__ASSEMBLY__ */ diff --git a/arch/powerpc/kernel/module.c b/arch/powerpc/kernel/module.c index 9547381b631a..340528d79233 100644 --- a/arch/powerpc/kernel/module.c +++ b/arch/powerpc/kernel/module.c @@ -67,6 +67,12 @@ int module_finalize(const Elf_Ehdr *hdr, do_feature_fixups(powerpc_firmware_features, (void *)sect->sh_addr, (void *)sect->sh_addr + sect->sh_size); + + sect = find_section(hdr, sechdrs, "__spec_barrier_fixup"); + if (sect != NULL) + do_barrier_nospec_fixups_range(barrier_nospec_enabled, + (void *)sect->sh_addr, + (void *)sect->sh_addr + sect->sh_size); #endif sect = find_section(hdr, sechdrs, "__lwsync_fixup"); diff --git a/arch/powerpc/kernel/security.c b/arch/powerpc/kernel/security.c index 0b7f6471f8f5..a1ae02f9d03d 100644 --- a/arch/powerpc/kernel/security.c +++ b/arch/powerpc/kernel/security.c @@ -16,7 +16,7 @@ unsigned long powerpc_security_features __read_mostly = SEC_FTR_DEFAULT; -static bool barrier_nospec_enabled; +bool barrier_nospec_enabled; static void enable_barrier_nospec(bool enable) { diff --git a/arch/powerpc/lib/feature-fixups.c b/arch/powerpc/lib/feature-fixups.c index 17a3c2d5c80b..e9373f41f0da 100644 --- a/arch/powerpc/lib/feature-fixups.c +++ b/arch/powerpc/lib/feature-fixups.c @@ -275,14 +275,14 @@ void do_rfi_flush_fixups(enum l1d_flush_type types) : "unknown"); } -void do_barrier_nospec_fixups(bool enable) +void do_barrier_nospec_fixups_range(bool enable, void *fixup_start, void *fixup_end) { unsigned int instr, *dest; long *start, *end; int i; - start = PTRRELOC(&__start___barrier_nospec_fixup), - end = PTRRELOC(&__stop___barrier_nospec_fixup); + start = fixup_start; + end = fixup_end; instr = 0x60000000; /* nop */ @@ -301,6 +301,16 @@ void do_barrier_nospec_fixups(bool enable) printk(KERN_DEBUG "barrier-nospec: patched %d locations\n", i); } +void do_barrier_nospec_fixups(bool enable) +{ + void *start, *end; + + start = PTRRELOC(&__start___barrier_nospec_fixup), + end = PTRRELOC(&__stop___barrier_nospec_fixup); + + do_barrier_nospec_fixups_range(enable, start, end); +} + #endif /* CONFIG_PPC_BOOK3S_64 */ void do_lwsync_fixups(unsigned long value, void *fixup_start, void *fixup_end)