From: Ye Bin <yebin10@huawei.com> ohos inclusion category: feature feature: ARM kaslr support issue: #I3ZXZF CVE: NA ------------------------------------------------- Signed-off-by: Ye Bin <yebin10@huawei.com> Reviewed-by: Jason Yan <yanaijie@huawei.com> Signed-off-by: yangerkun <yangerkun@huawei.com> Signed-off-by: Cui GaoSheng <cuigaosheng1@huawei.com> Reviewed-by: Xiu Jianfeng <xiujianfeng@huawei.com> Signed-off-by: Chen Jun <chenjun102@huawei.com> Signed-off-by: Yu Changchun <yuchangchun1@huawei.com> --- arch/arm/include/asm/memory.h | 14 ++++++++++++++ arch/arm/kernel/head.S | 2 +- arch/arm/kernel/setup.c | 30 ++++++++++++++++++++++++++++++ 3 files changed, 45 insertions(+), 1 deletion(-) diff --git a/arch/arm/include/asm/memory.h b/arch/arm/include/asm/memory.h index 2f841cb65c30..a7a22bf5ca7e 100644 --- a/arch/arm/include/asm/memory.h +++ b/arch/arm/include/asm/memory.h @@ -167,6 +167,20 @@ extern unsigned long vectors_base; #ifndef __ASSEMBLY__ +#ifdef CONFIG_RANDOMIZE_BASE +extern unsigned long __kaslr_offset; + +static inline unsigned long kaslr_offset(void) +{ + return __kaslr_offset; +} +#else +static inline unsigned long kaslr_offset(void) +{ + return 0; +} +#endif + /* * Physical vs virtual RAM address space conversion. These are * private definitions which should NOT be used outside memory.h diff --git a/arch/arm/kernel/head.S b/arch/arm/kernel/head.S index 26f3e9a0ffe9..b6b82387289b 100644 --- a/arch/arm/kernel/head.S +++ b/arch/arm/kernel/head.S @@ -105,7 +105,7 @@ ENTRY(stext) .section ".bss", "aw", %nobits .align 2 -__kaslr_offset: +ENTRY(__kaslr_offset) .long 0 @ will be wiped before entering C code .previous #endif diff --git a/arch/arm/kernel/setup.c b/arch/arm/kernel/setup.c index d32f7652a5bf..e37ebb7f1b0b 100644 --- a/arch/arm/kernel/setup.c +++ b/arch/arm/kernel/setup.c @@ -1338,3 +1338,33 @@ const struct seq_operations cpuinfo_op = { .stop = c_stop, .show = c_show }; + +/* + * Dump out kernel offset information on panic. + */ +static int dump_kernel_offset(struct notifier_block *self, unsigned long v, + void *p) +{ + const unsigned long offset = kaslr_offset(); + + if (IS_ENABLED(CONFIG_RANDOMIZE_BASE) && offset > 0) { + pr_emerg("Kernel Offset: 0x%lx from 0x%lx\n", + offset, PAGE_OFFSET); + + } else { + pr_emerg("Kernel Offset: disabled\n"); + } + return 0; +} + +static struct notifier_block kernel_offset_notifier = { + .notifier_call = dump_kernel_offset +}; + +static int __init register_kernel_offset_dumper(void) +{ + atomic_notifier_chain_register(&panic_notifier_list, + &kernel_offset_notifier); + return 0; +} +__initcall(register_kernel_offset_dumper); -- 2.22.0