arm64: signal: nofpsimd: Handle fp/simd context for signal frames

Make sure we try to save/restore the vfp/fpsimd context for signal
handling only when the fp/simd support is available. Otherwise, skip
the frames.

Cc: Will Deacon <will@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Reviewed-by: Ard Biesheuvel <ardb@kernel.org>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Will Deacon <will@kernel.org>

diff --git a/arch/arm64/kernel/signal.c b/arch/arm64/kernel/signal.c
index dd2cdc0..339882d 100644 (file)
--- a/arch/arm64/kernel/signal.c
+++ b/arch/arm64/kernel/signal.c
@@ -371,6 +371,8 @@ static int parse_user_sigframe(struct user_ctxs *user,
                        goto done;
 
                case FPSIMD_MAGIC:
+                       if (!system_supports_fpsimd())
+                               goto invalid;
                        if (user->fpsimd)
                                goto invalid;
 
@@ -506,7 +508,7 @@ static int restore_sigframe(struct pt_regs *regs,
        if (err == 0)
                err = parse_user_sigframe(&user, sf);
 
-       if (err == 0) {
+       if (err == 0 && system_supports_fpsimd()) {
                if (!user.fpsimd)
                        return -EINVAL;
 
@@ -623,7 +625,7 @@ static int setup_sigframe(struct rt_sigframe_user_layout *user,
 
        err |= __copy_to_user(&sf->uc.uc_sigmask, set, sizeof(*set));
 
-       if (err == 0) {
+       if (err == 0 && system_supports_fpsimd()) {
                struct fpsimd_context __user *fpsimd_ctx =
                        apply_user_offset(user, user->fpsimd_offset);
                err |= preserve_fpsimd_context(fpsimd_ctx);

diff --git a/arch/arm64/kernel/signal32.c b/arch/arm64/kernel/signal32.c
index 12a5853..82feca6 100644 (file)
--- a/arch/arm64/kernel/signal32.c
+++ b/arch/arm64/kernel/signal32.c
@@ -223,7 +223,7 @@ static int compat_restore_sigframe(struct pt_regs *regs,
        err |= !valid_user_regs(&regs->user_regs, current);
 
        aux = (struct compat_aux_sigframe __user *) sf->uc.uc_regspace;
-       if (err == 0)
+       if (err == 0 && system_supports_fpsimd())
                err |= compat_restore_vfp_context(&aux->vfp);
 
        return err;
@@ -419,7 +419,7 @@ static int compat_setup_sigframe(struct compat_sigframe __user *sf,
 
        aux = (struct compat_aux_sigframe __user *) sf->uc.uc_regspace;
 
-       if (err == 0)
+       if (err == 0 && system_supports_fpsimd())
                err |= compat_preserve_vfp_context(&aux->vfp);
        __put_user_error(0, &aux->end_magic, err);