4.9-stable review patch. If anyone has any objections, please let me know.
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Commit 5ca451cf6ed04443774bbb7ee45332dafa42e99f upstream.
When saving the ARM integer registers, use __copy_to_user() to copy them into user signal frame, rather than __put_user_error(). This has the benefit of disabling/enabling PAN once for the whole copy intead of once per write.
Signed-off-by: Julien Thierry julien.thierry@arm.com Signed-off-by: Russell King rmk+kernel@armlinux.org.uk Signed-off-by: David A. Long dave.long@linaro.org Reviewed-by: Julien Thierry julien.thierry@arm.com Signed-off-by: Sasha Levin sashal@kernel.org --- arch/arm/kernel/signal.c | 49 ++++++++++++++++++++++------------------ 1 file changed, 27 insertions(+), 22 deletions(-)
diff --git a/arch/arm/kernel/signal.c b/arch/arm/kernel/signal.c index 6bee5c9b1133..fbb325ff8acc 100644 --- a/arch/arm/kernel/signal.c +++ b/arch/arm/kernel/signal.c @@ -256,30 +256,35 @@ static int setup_sigframe(struct sigframe __user *sf, struct pt_regs *regs, sigset_t *set) { struct aux_sigframe __user *aux; + struct sigcontext context; int err = 0;
- __put_user_error(regs->ARM_r0, &sf->uc.uc_mcontext.arm_r0, err); - __put_user_error(regs->ARM_r1, &sf->uc.uc_mcontext.arm_r1, err); - __put_user_error(regs->ARM_r2, &sf->uc.uc_mcontext.arm_r2, err); - __put_user_error(regs->ARM_r3, &sf->uc.uc_mcontext.arm_r3, err); - __put_user_error(regs->ARM_r4, &sf->uc.uc_mcontext.arm_r4, err); - __put_user_error(regs->ARM_r5, &sf->uc.uc_mcontext.arm_r5, err); - __put_user_error(regs->ARM_r6, &sf->uc.uc_mcontext.arm_r6, err); - __put_user_error(regs->ARM_r7, &sf->uc.uc_mcontext.arm_r7, err); - __put_user_error(regs->ARM_r8, &sf->uc.uc_mcontext.arm_r8, err); - __put_user_error(regs->ARM_r9, &sf->uc.uc_mcontext.arm_r9, err); - __put_user_error(regs->ARM_r10, &sf->uc.uc_mcontext.arm_r10, err); - __put_user_error(regs->ARM_fp, &sf->uc.uc_mcontext.arm_fp, err); - __put_user_error(regs->ARM_ip, &sf->uc.uc_mcontext.arm_ip, err); - __put_user_error(regs->ARM_sp, &sf->uc.uc_mcontext.arm_sp, err); - __put_user_error(regs->ARM_lr, &sf->uc.uc_mcontext.arm_lr, err); - __put_user_error(regs->ARM_pc, &sf->uc.uc_mcontext.arm_pc, err); - __put_user_error(regs->ARM_cpsr, &sf->uc.uc_mcontext.arm_cpsr, err); - - __put_user_error(current->thread.trap_no, &sf->uc.uc_mcontext.trap_no, err); - __put_user_error(current->thread.error_code, &sf->uc.uc_mcontext.error_code, err); - __put_user_error(current->thread.address, &sf->uc.uc_mcontext.fault_address, err); - __put_user_error(set->sig[0], &sf->uc.uc_mcontext.oldmask, err); + context = (struct sigcontext) { + .arm_r0 = regs->ARM_r0, + .arm_r1 = regs->ARM_r1, + .arm_r2 = regs->ARM_r2, + .arm_r3 = regs->ARM_r3, + .arm_r4 = regs->ARM_r4, + .arm_r5 = regs->ARM_r5, + .arm_r6 = regs->ARM_r6, + .arm_r7 = regs->ARM_r7, + .arm_r8 = regs->ARM_r8, + .arm_r9 = regs->ARM_r9, + .arm_r10 = regs->ARM_r10, + .arm_fp = regs->ARM_fp, + .arm_ip = regs->ARM_ip, + .arm_sp = regs->ARM_sp, + .arm_lr = regs->ARM_lr, + .arm_pc = regs->ARM_pc, + .arm_cpsr = regs->ARM_cpsr, + + .trap_no = current->thread.trap_no, + .error_code = current->thread.error_code, + .fault_address = current->thread.address, + .oldmask = set->sig[0], + }; + + err |= __copy_to_user(&sf->uc.uc_mcontext, &context, sizeof(context));
err |= __copy_to_user(&sf->uc.uc_sigmask, set, sizeof(*set));