From: Will Deacon will.deacon@arm.com
mainline inclusion from v4.20-rc3 commit 84931327a807 category: feature bugzilla: 27615 CVE: NA
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We don't need to get at the per-thread keys from assembly at all, so they can live alongside the rest of the per-thread register state in thread_struct instead of thread_info.
This will also allow straighforward whitelisting of the keys for hardened usercopy should we expose them via a ptrace request later on.
Signed-off-by: Will Deacon will.deacon@arm.com
Conflicts: arch/arm64/include/asm/thread_info.h [Zheng Zengkai: fix conflicts caused by skipping the following commit. 396244 arm64: preempt: Provide our own implementation of asm/preempt.h]
Signed-off-by: Zheng Zengkai zhengzengkai@huawei.com Reviewed-by: Hanjun Guo guohanjun@huawei.com Signed-off-by: Yang Yingliang yangyingliang@huawei.com --- arch/arm64/include/asm/pointer_auth.h | 6 +++--- arch/arm64/include/asm/processor.h | 3 +++ arch/arm64/include/asm/thread_info.h | 4 ---- arch/arm64/kernel/pointer_auth.c | 2 +- 4 files changed, 7 insertions(+), 8 deletions(-)
diff --git a/arch/arm64/include/asm/pointer_auth.h b/arch/arm64/include/asm/pointer_auth.h index 55cc128b9a81e..2a42d40fafa1c 100644 --- a/arch/arm64/include/asm/pointer_auth.h +++ b/arch/arm64/include/asm/pointer_auth.h @@ -80,12 +80,12 @@ static inline unsigned long ptrauth_strip_insn_pac(unsigned long ptr) #define ptrauth_thread_init_user(tsk) \ do { \ struct task_struct *__ptiu_tsk = (tsk); \ - ptrauth_keys_init(&__ptiu_tsk->thread_info.keys_user); \ - ptrauth_keys_switch(&__ptiu_tsk->thread_info.keys_user); \ + ptrauth_keys_init(&__ptiu_tsk->thread.keys_user); \ + ptrauth_keys_switch(&__ptiu_tsk->thread.keys_user); \ } while (0)
#define ptrauth_thread_switch(tsk) \ - ptrauth_keys_switch(&(tsk)->thread_info.keys_user) + ptrauth_keys_switch(&(tsk)->thread.keys_user)
#else /* CONFIG_ARM64_PTR_AUTH */ #define ptrauth_prctl_reset_keys(tsk, arg) (-EINVAL) diff --git a/arch/arm64/include/asm/processor.h b/arch/arm64/include/asm/processor.h index 79a9df5b767c1..e66293afd6f3d 100644 --- a/arch/arm64/include/asm/processor.h +++ b/arch/arm64/include/asm/processor.h @@ -144,6 +144,9 @@ struct thread_struct { unsigned long fault_address; /* fault info */ unsigned long fault_code; /* ESR_EL1 value */ struct debug_info debug; /* debugging */ +#ifdef CONFIG_ARM64_PTR_AUTH + struct ptrauth_keys keys_user; +#endif };
static inline void arch_thread_struct_whitelist(unsigned long *offset, diff --git a/arch/arm64/include/asm/thread_info.h b/arch/arm64/include/asm/thread_info.h index 3422c50e4f449..01f063a81d648 100644 --- a/arch/arm64/include/asm/thread_info.h +++ b/arch/arm64/include/asm/thread_info.h @@ -28,7 +28,6 @@ struct task_struct;
#include <asm/memory.h> -#include <asm/pointer_auth.h> #include <asm/stack_pointer.h> #include <asm/types.h>
@@ -44,9 +43,6 @@ struct thread_info { u64 ttbr0; /* saved TTBR0_EL1 */ #endif int preempt_count; /* 0 => preemptable, <0 => bug */ -#ifdef CONFIG_ARM64_PTR_AUTH - struct ptrauth_keys keys_user; -#endif };
#define thread_saved_pc(tsk) \ diff --git a/arch/arm64/kernel/pointer_auth.c b/arch/arm64/kernel/pointer_auth.c index b9f6f5f3409a5..c507b584259d0 100644 --- a/arch/arm64/kernel/pointer_auth.c +++ b/arch/arm64/kernel/pointer_auth.c @@ -9,7 +9,7 @@
int ptrauth_prctl_reset_keys(struct task_struct *tsk, unsigned long arg) { - struct ptrauth_keys *keys = &tsk->thread_info.keys_user; + struct ptrauth_keys *keys = &tsk->thread.keys_user; unsigned long addr_key_mask = PR_PAC_APIAKEY | PR_PAC_APIBKEY | PR_PAC_APDAKEY | PR_PAC_APDBKEY; unsigned long key_mask = addr_key_mask | PR_PAC_APGAKEY;