diff options
| author | Will Deacon <will.deacon@arm.com> | 2018-02-02 20:31:39 +0300 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2018-02-16 22:22:53 +0300 |
| commit | 6b47a8256a56c261ab008863a548f245fdcc8b11 (patch) | |
| tree | b1d0adcc0a7e74473ec1ba09f5f98b926d485cc3 /arch | |
| parent | aab3306701f10c5dc35d8da74431cde6249baf0b (diff) | |
| download | linux-6b47a8256a56c261ab008863a548f245fdcc8b11.tar.xz | |
arm64: entry: Apply BP hardening for high-priority synchronous exceptions
Commit 5dfc6ed27710 upstream.
Software-step and PC alignment fault exceptions have higher priority than
instruction abort exceptions, so apply the BP hardening hooks there too
if the user PC appears to reside in kernel space.
Reported-by: Dan Hettena <dhettena@nvidia.com>
Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'arch')
| -rw-r--r-- | arch/arm64/kernel/entry.S | 6 | ||||
| -rw-r--r-- | arch/arm64/mm/fault.c | 9 |
2 files changed, 13 insertions, 2 deletions
diff --git a/arch/arm64/kernel/entry.S b/arch/arm64/kernel/entry.S index a035a981b557..ac7df45b296b 100644 --- a/arch/arm64/kernel/entry.S +++ b/arch/arm64/kernel/entry.S @@ -759,8 +759,10 @@ el0_sp_pc: * Stack or PC alignment exception handling */ mrs x26, far_el1 - // enable interrupts before calling the main handler - enable_dbg_and_irq + enable_dbg +#ifdef CONFIG_TRACE_IRQFLAGS + bl trace_hardirqs_off +#endif ct_user_exit mov x0, x26 mov x1, x25 diff --git a/arch/arm64/mm/fault.c b/arch/arm64/mm/fault.c index 4985bd1175ef..58992467ebb9 100644 --- a/arch/arm64/mm/fault.c +++ b/arch/arm64/mm/fault.c @@ -778,6 +778,12 @@ asmlinkage void __exception do_sp_pc_abort(unsigned long addr, struct siginfo info; struct task_struct *tsk = current; + if (user_mode(regs)) { + if (instruction_pointer(regs) > TASK_SIZE) + arm64_apply_bp_hardening(); + local_irq_enable(); + } + if (show_unhandled_signals && unhandled_signal(tsk, SIGBUS)) pr_info_ratelimited("%s[%d]: %s exception: pc=%p sp=%p\n", tsk->comm, task_pid_nr(tsk), @@ -837,6 +843,9 @@ asmlinkage int __exception do_debug_exception(unsigned long addr, if (interrupts_enabled(regs)) trace_hardirqs_off(); + if (user_mode(regs) && instruction_pointer(regs) > TASK_SIZE) + arm64_apply_bp_hardening(); + if (!inf->fn(addr, esr, regs)) { rv = 1; } else { |