diff options
| author | Kristina Martsenko <kristina.martsenko@arm.com> | 2020-03-13 12:04:51 +0300 |
|---|---|---|
| committer | Catalin Marinas <catalin.marinas@arm.com> | 2020-03-18 12:50:19 +0300 |
| commit | be129842566599f2c6f8fbba277c098802cd4b3d (patch) | |
| tree | 99ba6277bb813d8d239e52bfebad736d707a4080 /arch/arm64/kernel | |
| parent | 91a1b6ccff323e60615e3118eceb2d8cbc4f69ab (diff) | |
| download | linux-be129842566599f2c6f8fbba277c098802cd4b3d.tar.xz | |
arm64: install user ptrauth keys at kernel exit time
As we're going to enable pointer auth within the kernel and use a
different APIAKey for the kernel itself, so move the user APIAKey
switch to EL0 exception return.
The other 4 keys could remain switched during task switch, but are also
moved to keep things consistent.
Reviewed-by: Kees Cook <keescook@chromium.org>
Reviewed-by: James Morse <james.morse@arm.com>
Reviewed-by: Vincenzo Frascino <Vincenzo.Frascino@arm.com>
Signed-off-by: Kristina Martsenko <kristina.martsenko@arm.com>
[Amit: commit msg, re-positioned the patch, comments]
Signed-off-by: Amit Daniel Kachhap <amit.kachhap@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Diffstat (limited to 'arch/arm64/kernel')
| -rw-r--r-- | arch/arm64/kernel/asm-offsets.c | 11 | ||||
| -rw-r--r-- | arch/arm64/kernel/entry.S | 3 | ||||
| -rw-r--r-- | arch/arm64/kernel/pointer_auth.c | 3 | ||||
| -rw-r--r-- | arch/arm64/kernel/process.c | 1 |
4 files changed, 14 insertions, 4 deletions
diff --git a/arch/arm64/kernel/asm-offsets.c b/arch/arm64/kernel/asm-offsets.c index a5bdce8af65b..7b1ea2aece58 100644 --- a/arch/arm64/kernel/asm-offsets.c +++ b/arch/arm64/kernel/asm-offsets.c @@ -40,6 +40,9 @@ int main(void) #endif BLANK(); DEFINE(THREAD_CPU_CONTEXT, offsetof(struct task_struct, thread.cpu_context)); +#ifdef CONFIG_ARM64_PTR_AUTH + DEFINE(THREAD_KEYS_USER, offsetof(struct task_struct, thread.keys_user)); +#endif BLANK(); DEFINE(S_X0, offsetof(struct pt_regs, regs[0])); DEFINE(S_X2, offsetof(struct pt_regs, regs[2])); @@ -128,5 +131,13 @@ int main(void) DEFINE(SDEI_EVENT_INTREGS, offsetof(struct sdei_registered_event, interrupted_regs)); DEFINE(SDEI_EVENT_PRIORITY, offsetof(struct sdei_registered_event, priority)); #endif +#ifdef CONFIG_ARM64_PTR_AUTH + DEFINE(PTRAUTH_USER_KEY_APIA, offsetof(struct ptrauth_keys_user, apia)); + DEFINE(PTRAUTH_USER_KEY_APIB, offsetof(struct ptrauth_keys_user, apib)); + DEFINE(PTRAUTH_USER_KEY_APDA, offsetof(struct ptrauth_keys_user, apda)); + DEFINE(PTRAUTH_USER_KEY_APDB, offsetof(struct ptrauth_keys_user, apdb)); + DEFINE(PTRAUTH_USER_KEY_APGA, offsetof(struct ptrauth_keys_user, apga)); + BLANK(); +#endif return 0; } diff --git a/arch/arm64/kernel/entry.S b/arch/arm64/kernel/entry.S index 9461d812ae27..684e475bfda0 100644 --- a/arch/arm64/kernel/entry.S +++ b/arch/arm64/kernel/entry.S @@ -14,6 +14,7 @@ #include <asm/alternative.h> #include <asm/assembler.h> #include <asm/asm-offsets.h> +#include <asm/asm_pointer_auth.h> #include <asm/cpufeature.h> #include <asm/errno.h> #include <asm/esr.h> @@ -341,6 +342,8 @@ alternative_else_nop_endif msr cntkctl_el1, x1 4: #endif + ptrauth_keys_install_user tsk, x0, x1, x2 + apply_ssbd 0, x0, x1 .endif diff --git a/arch/arm64/kernel/pointer_auth.c b/arch/arm64/kernel/pointer_auth.c index af5a638207f8..1e77736a4f66 100644 --- a/arch/arm64/kernel/pointer_auth.c +++ b/arch/arm64/kernel/pointer_auth.c @@ -19,7 +19,6 @@ int ptrauth_prctl_reset_keys(struct task_struct *tsk, unsigned long arg) if (!arg) { ptrauth_keys_init_user(keys); - ptrauth_keys_switch_user(keys); return 0; } @@ -41,7 +40,5 @@ int ptrauth_prctl_reset_keys(struct task_struct *tsk, unsigned long arg) if (arg & PR_PAC_APGAKEY) get_random_bytes(&keys->apga, sizeof(keys->apga)); - ptrauth_keys_switch_user(keys); - return 0; } diff --git a/arch/arm64/kernel/process.c b/arch/arm64/kernel/process.c index 00626057a384..6140e791bf92 100644 --- a/arch/arm64/kernel/process.c +++ b/arch/arm64/kernel/process.c @@ -512,7 +512,6 @@ __notrace_funcgraph struct task_struct *__switch_to(struct task_struct *prev, contextidr_thread_switch(next); entry_task_switch(next); uao_thread_switch(next); - ptrauth_thread_switch(next); ssbs_thread_switch(next); /* |