diff options
author | Linus Walleij <linus.walleij@linaro.org> | 2024-04-23 10:29:31 +0300 |
---|---|---|
committer | Russell King (Oracle) <rmk+kernel@armlinux.org.uk> | 2024-04-29 16:14:16 +0300 |
commit | 1036b89580dc611cfb5dfe66af6b35452dfb272c (patch) | |
tree | 8af0e6080d0557da7d6bfb095f23022debf50052 /arch/arm/mm/proc-arm940.S | |
parent | 6b0ef2792c223636a86f2c9c3fcb26502a03d5a7 (diff) | |
download | linux-1036b89580dc611cfb5dfe66af6b35452dfb272c.tar.xz |
ARM: 9385/2: mm: Type-annotate all cache assembly routines
Tag all references to assembly functions with SYM_TYPED_FUNC_START()
and SYM_FUNC_END() so they also become CFI-safe.
When we add SYM_TYPED_FUNC_START() to assembly calls, a function
prototype signature will be emitted into the object file at
(pc-4) at the call site, so that the KCFI runtime check can compare
this to the expected call. Example:
8011ae38: a540670c .word 0xa540670c
8011ae3c <v7_flush_icache_all>:
8011ae3c: e3a00000 mov r0, #0
8011ae40: ee070f11 mcr 15, 0, r0, cr7, cr1, {0}
8011ae44: e12fff1e bx lr
This means no "fallthrough" code can enter a SYM_TYPED_FUNC_START()
call from above it: there will be a function prototype signature
there, so those are consistently converted to a branch or ret lr
depending on context.
Tested-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Sami Tolvanen <samitolvanen@google.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Diffstat (limited to 'arch/arm/mm/proc-arm940.S')
-rw-r--r-- | arch/arm/mm/proc-arm940.S | 42 |
1 files changed, 25 insertions, 17 deletions
diff --git a/arch/arm/mm/proc-arm940.S b/arch/arm/mm/proc-arm940.S index cf9bfcc825ca..7e32ec271e8a 100644 --- a/arch/arm/mm/proc-arm940.S +++ b/arch/arm/mm/proc-arm940.S @@ -6,6 +6,7 @@ */ #include <linux/linkage.h> #include <linux/init.h> +#include <linux/cfi_types.h> #include <linux/pgtable.h> #include <asm/assembler.h> #include <asm/hwcap.h> @@ -71,26 +72,28 @@ ENTRY(cpu_arm940_do_idle) * * Unconditionally clean and invalidate the entire icache. */ -ENTRY(arm940_flush_icache_all) +SYM_TYPED_FUNC_START(arm940_flush_icache_all) mov r0, #0 mcr p15, 0, r0, c7, c5, 0 @ invalidate I cache ret lr -ENDPROC(arm940_flush_icache_all) +SYM_FUNC_END(arm940_flush_icache_all) /* * flush_user_cache_all() */ -ENTRY(arm940_flush_user_cache_all) - /* FALLTHROUGH */ +SYM_TYPED_FUNC_START(arm940_flush_user_cache_all) + b arm940_flush_kern_cache_all +SYM_FUNC_END(arm940_flush_user_cache_all) /* * flush_kern_cache_all() * * Clean and invalidate the entire cache. */ -ENTRY(arm940_flush_kern_cache_all) +SYM_TYPED_FUNC_START(arm940_flush_kern_cache_all) mov r2, #VM_EXEC - /* FALLTHROUGH */ + b arm940_flush_user_cache_range +SYM_FUNC_END(arm940_flush_kern_cache_all) /* * flush_user_cache_range(start, end, flags) @@ -102,7 +105,7 @@ ENTRY(arm940_flush_kern_cache_all) * - end - end address (exclusive) * - flags - vm_flags describing address space */ -ENTRY(arm940_flush_user_cache_range) +SYM_TYPED_FUNC_START(arm940_flush_user_cache_range) mov ip, #0 #ifdef CONFIG_CPU_DCACHE_WRITETHROUGH mcr p15, 0, ip, c7, c6, 0 @ flush D cache @@ -119,6 +122,7 @@ ENTRY(arm940_flush_user_cache_range) mcrne p15, 0, ip, c7, c5, 0 @ invalidate I cache mcrne p15, 0, ip, c7, c10, 4 @ drain WB ret lr +SYM_FUNC_END(arm940_flush_user_cache_range) /* * coherent_kern_range(start, end) @@ -130,8 +134,9 @@ ENTRY(arm940_flush_user_cache_range) * - start - virtual start address * - end - virtual end address */ -ENTRY(arm940_coherent_kern_range) - /* FALLTHROUGH */ +SYM_TYPED_FUNC_START(arm940_coherent_kern_range) + b arm940_flush_kern_dcache_area +SYM_FUNC_END(arm940_coherent_kern_range) /* * coherent_user_range(start, end) @@ -143,8 +148,9 @@ ENTRY(arm940_coherent_kern_range) * - start - virtual start address * - end - virtual end address */ -ENTRY(arm940_coherent_user_range) - /* FALLTHROUGH */ +SYM_TYPED_FUNC_START(arm940_coherent_user_range) + b arm940_flush_kern_dcache_area +SYM_FUNC_END(arm940_coherent_user_range) /* * flush_kern_dcache_area(void *addr, size_t size) @@ -155,7 +161,7 @@ ENTRY(arm940_coherent_user_range) * - addr - kernel address * - size - region size */ -ENTRY(arm940_flush_kern_dcache_area) +SYM_TYPED_FUNC_START(arm940_flush_kern_dcache_area) mov r0, #0 mov r1, #(CACHE_DSEGMENTS - 1) << 4 @ 4 segments 1: orr r3, r1, #(CACHE_DENTRIES - 1) << 26 @ 64 entries @@ -167,6 +173,7 @@ ENTRY(arm940_flush_kern_dcache_area) mcr p15, 0, r0, c7, c5, 0 @ invalidate I cache mcr p15, 0, r0, c7, c10, 4 @ drain WB ret lr +SYM_FUNC_END(arm940_flush_kern_dcache_area) /* * dma_inv_range(start, end) @@ -222,7 +229,7 @@ ENTRY(cpu_arm940_dcache_clean_area) * - start - virtual start address * - end - virtual end address */ -ENTRY(arm940_dma_flush_range) +SYM_TYPED_FUNC_START(arm940_dma_flush_range) mov ip, #0 mov r1, #(CACHE_DSEGMENTS - 1) << 4 @ 4 segments 1: orr r3, r1, #(CACHE_DENTRIES - 1) << 26 @ 64 entries @@ -238,6 +245,7 @@ ENTRY(arm940_dma_flush_range) bcs 1b @ segments 7 to 0 mcr p15, 0, ip, c7, c10, 4 @ drain WB ret lr +SYM_FUNC_END(arm940_dma_flush_range) /* * dma_map_area(start, size, dir) @@ -245,13 +253,13 @@ ENTRY(arm940_dma_flush_range) * - size - size of region * - dir - DMA direction */ -ENTRY(arm940_dma_map_area) +SYM_TYPED_FUNC_START(arm940_dma_map_area) add r1, r1, r0 cmp r2, #DMA_TO_DEVICE beq arm940_dma_clean_range bcs arm940_dma_inv_range b arm940_dma_flush_range -ENDPROC(arm940_dma_map_area) +SYM_FUNC_END(arm940_dma_map_area) /* * dma_unmap_area(start, size, dir) @@ -259,9 +267,9 @@ ENDPROC(arm940_dma_map_area) * - size - size of region * - dir - DMA direction */ -ENTRY(arm940_dma_unmap_area) +SYM_TYPED_FUNC_START(arm940_dma_unmap_area) ret lr -ENDPROC(arm940_dma_unmap_area) +SYM_FUNC_END(arm940_dma_unmap_area) .globl arm940_flush_kern_cache_louis .equ arm940_flush_kern_cache_louis, arm940_flush_kern_cache_all |