Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18;
From:   Tiezhu Yang <yangtiezhu@loongson.cn>
To:     Paul Walmsley <paul.walmsley@sifive.com>,
        Palmer Dabbelt <palmer@dabbelt.com>,
        Albert Ou <aou@eecs.berkeley.edu>
Cc:     linux-riscv@lists.infradead.org, linux-kernel@vger.kernel.org
Subject: [PATCH] riscv: Return -EFAULT if copy_to_user() failed in signal.c
Date:   Tue,  2 Mar 2021 15:28:17 +0800
Message-Id: <1614670097-28536-1-git-send-email-yangtiezhu@loongson.cn>
Precedence: bulk

copy_to_user() returns the amount left to copy, it should return -EFAULT
if copy to user failed.

Signed-off-by: Tiezhu Yang <yangtiezhu@loongson.cn>
---
 arch/riscv/kernel/signal.c | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/arch/riscv/kernel/signal.c b/arch/riscv/kernel/signal.c
index 65942b3..2238fc5 100644
--- a/arch/riscv/kernel/signal.c
+++ b/arch/riscv/kernel/signal.c
@@ -67,7 +67,7 @@ static long save_fp_state(struct pt_regs *regs,
 	fstate_save(current, regs);
 	err = __copy_to_user(state, &current->thread.fstate, sizeof(*state));
 	if (unlikely(err))
-		return err;
+		return -EFAULT;
 
 	/* We support no other extension state at this time. */
 	for (i = 0; i < ARRAY_SIZE(sc_fpregs->q.reserved); i++) {
@@ -140,8 +140,12 @@ static long setup_sigcontext(struct rt_sigframe __user *frame,
 {
 	struct sigcontext __user *sc = &frame->uc.uc_mcontext;
 	long err;
+
 	/* sc_regs is structured the same as the start of pt_regs */
 	err = __copy_to_user(&sc->sc_regs, regs, sizeof(sc->sc_regs));
+	if (unlikely(err))
+		return -EFAULT;
+
 	/* Save the floating-point state. */
 	if (has_fpu)
 		err |= save_fp_state(regs, &sc->sc_fpregs);
-- 
2.1.0