From: Sami Tolvanen <samitolvanen@google.com>
To: Kees Cook <keescook@chromium.org>
Cc: Nathan Chancellor <nathan@kernel.org>,
Nick Desaulniers <ndesaulniers@google.com>,
Masahiro Yamada <masahiroy@kernel.org>,
Will Deacon <will@kernel.org>, Jessica Yu <jeyu@kernel.org>,
Arnd Bergmann <arnd@arndb.de>, Tejun Heo <tj@kernel.org>,
"Paul E. McKenney" <paulmck@kernel.org>,
Christoph Hellwig <hch@infradead.org>,
Peter Zijlstra <peterz@infradead.org>,
bpf@vger.kernel.org, linux-hardening@vger.kernel.org,
linux-arch@vger.kernel.org, linux-arm-kernel@lists.infradead.org,
linux-kbuild@vger.kernel.org, linux-pci@vger.kernel.org,
linux-kernel@vger.kernel.org,
Sami Tolvanen <samitolvanen@google.com>
Subject: [PATCH v3 12/17] arm64: implement __va_function
Date: Tue, 23 Mar 2021 13:39:41 -0700 [thread overview]
Message-ID: <20210323203946.2159693-13-samitolvanen@google.com> (raw)
In-Reply-To: <20210323203946.2159693-1-samitolvanen@google.com>
With CONFIG_CFI_CLANG, the compiler replaces function addresses in
instrumented C code with jump table addresses. This change implements
the __va_function() macro, which returns the actual function address
instead.
Signed-off-by: Sami Tolvanen <samitolvanen@google.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
---
arch/arm64/include/asm/memory.h | 15 +++++++++++++++
1 file changed, 15 insertions(+)
diff --git a/arch/arm64/include/asm/memory.h b/arch/arm64/include/asm/memory.h
index 0aabc3be9a75..9a4887808681 100644
--- a/arch/arm64/include/asm/memory.h
+++ b/arch/arm64/include/asm/memory.h
@@ -321,6 +321,21 @@ static inline void *phys_to_virt(phys_addr_t x)
#define virt_to_pfn(x) __phys_to_pfn(__virt_to_phys((unsigned long)(x)))
#define sym_to_pfn(x) __phys_to_pfn(__pa_symbol(x))
+#ifdef CONFIG_CFI_CLANG
+/*
+ * With CONFIG_CFI_CLANG, the compiler replaces function address
+ * references with the address of the function's CFI jump table
+ * entry. The __va_function macro always returns the address of the
+ * actual function instead.
+ */
+#define __va_function(x) ({ \
+ void *addr; \
+ asm("adrp %0, " __stringify(x) "\n\t" \
+ "add %0, %0, :lo12:" __stringify(x) : "=r" (addr)); \
+ addr; \
+})
+#endif
+
/*
* virt_to_page(x) convert a _valid_ virtual address to struct page *
* virt_addr_valid(x) indicates whether a virtual address is valid
--
2.31.0.291.g576ba9dcdaf-goog
next prev parent reply other threads:[~2021-03-23 20:41 UTC|newest]
Thread overview: 35+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-03-23 20:39 [PATCH v3 00/17] Add support for Clang CFI Sami Tolvanen
2021-03-23 20:39 ` [PATCH v3 01/17] add " Sami Tolvanen
2021-03-23 20:39 ` [PATCH v3 02/17] cfi: add __cficanonical Sami Tolvanen
2021-03-24 15:31 ` Rasmus Villemoes
2021-03-24 16:38 ` Sami Tolvanen
2021-03-23 20:39 ` [PATCH v3 03/17] mm: add generic __va_function and __pa_function macros Sami Tolvanen
2021-03-24 7:13 ` Christoph Hellwig
2021-03-24 15:54 ` Sami Tolvanen
2021-03-25 10:16 ` Mark Rutland
2021-03-25 23:17 ` Sami Tolvanen
2021-03-23 20:39 ` [PATCH v3 04/17] module: ensure __cfi_check alignment Sami Tolvanen
2021-03-26 4:34 ` Kees Cook
2021-03-29 9:26 ` Jessica Yu
2021-03-23 20:39 ` [PATCH v3 05/17] workqueue: use WARN_ON_FUNCTION_MISMATCH Sami Tolvanen
2021-03-26 4:34 ` Kees Cook
2021-03-23 20:39 ` [PATCH v3 06/17] kthread: " Sami Tolvanen
2021-03-26 4:35 ` Kees Cook
2021-03-23 20:39 ` [PATCH v3 07/17] kallsyms: strip ThinLTO hashes from static functions Sami Tolvanen
2021-03-23 20:39 ` [PATCH v3 08/17] bpf: disable CFI in dispatcher functions Sami Tolvanen
2021-03-23 20:39 ` [PATCH v3 09/17] treewide: Change list_sort to use const pointers Sami Tolvanen
2021-03-23 21:28 ` Nick Desaulniers
2021-03-24 7:10 ` Christoph Hellwig
2021-03-26 4:35 ` Kees Cook
2021-03-23 20:39 ` [PATCH v3 10/17] lkdtm: use __va_function Sami Tolvanen
2021-03-23 20:39 ` [PATCH v3 11/17] psci: use __pa_function for cpu_resume Sami Tolvanen
2021-03-25 10:23 ` Mark Rutland
2021-03-23 20:39 ` Sami Tolvanen [this message]
2021-03-25 10:37 ` [PATCH v3 12/17] arm64: implement __va_function Mark Rutland
2021-03-25 23:27 ` Sami Tolvanen
2021-03-26 0:03 ` Peter Collingbourne
2021-03-23 20:39 ` [PATCH v3 13/17] arm64: use __pa_function Sami Tolvanen
2021-03-23 20:39 ` [PATCH v3 14/17] arm64: add __nocfi to functions that jump to a physical address Sami Tolvanen
2021-03-23 20:39 ` [PATCH v3 15/17] arm64: add __nocfi to __apply_alternatives Sami Tolvanen
2021-03-23 20:39 ` [PATCH v3 16/17] KVM: arm64: Disable CFI for nVHE Sami Tolvanen
2021-03-23 20:39 ` [PATCH v3 17/17] arm64: allow CONFIG_CFI_CLANG to be selected Sami Tolvanen
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