[PATCH AUTOSEL 4.9 03/23] arc: kernel: Return -EFAULT if copy_to_user() fails

[Sasha Levin]

From: Wang Qing <wangqing at vivo.com>

[ Upstream commit 46e152186cd89d940b26726fff11eb3f4935b45a ]

The copy_to_user() function returns the number of bytes remaining to be
copied, but we want to return -EFAULT if the copy doesn't complete.

Signed-off-by: Wang Qing <wangqing at vivo.com>
Signed-off-by: Vineet Gupta <vgupta at synopsys.com>
Signed-off-by: Sasha Levin <sashal at kernel.org>
---
 arch/arc/kernel/signal.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/arch/arc/kernel/signal.c b/arch/arc/kernel/signal.c
index d347bbc086fe..16cdb471d3db 100644
--- a/arch/arc/kernel/signal.c
+++ b/arch/arc/kernel/signal.c
@@ -97,7 +97,7 @@ stash_usr_regs(struct rt_sigframe __user *sf, struct pt_regs *regs,
 			     sizeof(sf->uc.uc_mcontext.regs.scratch));
 	err |= __copy_to_user(&sf->uc.uc_sigmask, set, sizeof(sigset_t));
 
-	return err;
+	return err ? -EFAULT : 0;
 }
 
 static int restore_usr_regs(struct pt_regs *regs, struct rt_sigframe __user *sf)
@@ -111,7 +111,7 @@ static int restore_usr_regs(struct pt_regs *regs, struct rt_sigframe __user *sf)
 				&(sf->uc.uc_mcontext.regs.scratch),
 				sizeof(sf->uc.uc_mcontext.regs.scratch));
 	if (err)
-		return err;
+		return -EFAULT;
 
 	set_current_blocked(&set);
 	regs->bta	= uregs.scratch.bta;
-- 
2.30.2