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authorLecopzer Chen <lecopzer.chen@mediatek.com>2021-03-24 12:05:21 +0800
committerCatalin Marinas <catalin.marinas@arm.com>2021-03-29 12:35:05 +0100
commit31d02e7ab00873befd2cfb6e44581490d947c38b (patch)
treeea2440bcbb811caabbcd2b51802f70ea160a718c /arch/arm64/kernel/kaslr.c
parent71b613fc0c69080262f4ebe810c3d909d7ff8132 (diff)
arm64: kaslr: support randomized module area with KASAN_VMALLOC
After KASAN_VMALLOC works in arm64, we can randomize module region into vmalloc area now. Test: VMALLOC area ffffffc010000000 fffffffdf0000000 before the patch: module_alloc_base/end ffffffc008b80000 ffffffc010000000 after the patch: module_alloc_base/end ffffffdcf4bed000 ffffffc010000000 And the function that insmod some modules is fine. Suggested-by: Ard Biesheuvel <ardb@kernel.org> Signed-off-by: Lecopzer Chen <lecopzer.chen@mediatek.com> Link: https://lore.kernel.org/r/20210324040522.15548-5-lecopzer.chen@mediatek.com Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Diffstat (limited to 'arch/arm64/kernel/kaslr.c')
-rw-r--r--arch/arm64/kernel/kaslr.c18
1 files changed, 10 insertions, 8 deletions
diff --git a/arch/arm64/kernel/kaslr.c b/arch/arm64/kernel/kaslr.c
index 27f8939deb1b..341342b207f6 100644
--- a/arch/arm64/kernel/kaslr.c
+++ b/arch/arm64/kernel/kaslr.c
@@ -128,15 +128,17 @@ u64 __init kaslr_early_init(void)
/* use the top 16 bits to randomize the linear region */
memstart_offset_seed = seed >> 48;
- if (IS_ENABLED(CONFIG_KASAN_GENERIC) ||
- IS_ENABLED(CONFIG_KASAN_SW_TAGS))
+ if (!IS_ENABLED(CONFIG_KASAN_VMALLOC) &&
+ (IS_ENABLED(CONFIG_KASAN_GENERIC) ||
+ IS_ENABLED(CONFIG_KASAN_SW_TAGS)))
/*
- * KASAN does not expect the module region to intersect the
- * vmalloc region, since shadow memory is allocated for each
- * module at load time, whereas the vmalloc region is shadowed
- * by KASAN zero pages. So keep modules out of the vmalloc
- * region if KASAN is enabled, and put the kernel well within
- * 4 GB of the module region.
+ * KASAN without KASAN_VMALLOC does not expect the module region
+ * to intersect the vmalloc region, since shadow memory is
+ * allocated for each module at load time, whereas the vmalloc
+ * region is shadowed by KASAN zero pages. So keep modules
+ * out of the vmalloc region if KASAN is enabled without
+ * KASAN_VMALLOC, and put the kernel well within 4 GB of the
+ * module region.
*/
return offset % SZ_2G;