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From:   Sergey Shtylyov <s.shtylyov@omp.ru>
To:     Oleg Nesterov <oleg@redhat.com>,
        Catalin Marinas <catalin.marinas@arm.com>,
        Will Deacon <will@kernel.org>,
        <linux-arm-kernel@lists.infradead.org>,
        <linux-kernel@vger.kernel.org>
CC:     Andrew Morton <akpm@linux-foundation.org>,
        <lvc-patches@linuxtesting.org>, <lvc-project@linuxtesting.org>
Subject: [PATCH 03/13] arm64: ptrace: user_regset_copyin_ignore() always returns 0
Date:   Sat, 15 Oct 2022 00:22:25 +0300
Message-ID: <20221014212235.10770-4-s.shtylyov@omp.ru>
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user_regset_copyin_ignore() always returns 0, so checking its result seems
pointless -- don't do this anymore...

Found by Linux Verification Center (linuxtesting.org) with the SVACE static
analysis tool.

Signed-off-by: Sergey Shtylyov <s.shtylyov@omp.ru>
---
 arch/arm64/kernel/ptrace.c | 16 ++++------------
 1 file changed, 4 insertions(+), 12 deletions(-)

diff --git a/arch/arm64/kernel/ptrace.c b/arch/arm64/kernel/ptrace.c
index c2fb5755bbec..f3af3371280a 100644
--- a/arch/arm64/kernel/ptrace.c
+++ b/arch/arm64/kernel/ptrace.c
@@ -514,9 +514,7 @@ static int hw_break_set(struct task_struct *target,
 
 	/* Resource info and pad */
 	offset = offsetof(struct user_hwdebug_state, dbg_regs);
-	ret = user_regset_copyin_ignore(&pos, &count, &kbuf, &ubuf, 0, offset);
-	if (ret)
-		return ret;
+	user_regset_copyin_ignore(&pos, &count, &kbuf, &ubuf, 0, offset);
 
 	/* (address, ctrl) registers */
 	limit = regset->n * regset->size;
@@ -543,11 +541,8 @@ static int hw_break_set(struct task_struct *target,
 			return ret;
 		offset += PTRACE_HBP_CTRL_SZ;
 
-		ret = user_regset_copyin_ignore(&pos, &count, &kbuf, &ubuf,
-						offset,
-						offset + PTRACE_HBP_PAD_SZ);
-		if (ret)
-			return ret;
+		user_regset_copyin_ignore(&pos, &count, &kbuf, &ubuf,
+					  offset, offset + PTRACE_HBP_PAD_SZ);
 		offset += PTRACE_HBP_PAD_SZ;
 		idx++;
 	}
@@ -954,10 +949,7 @@ static int sve_set_common(struct task_struct *target,
 
 	start = end;
 	end = SVE_PT_SVE_FPSR_OFFSET(vq);
-	ret = user_regset_copyin_ignore(&pos, &count, &kbuf, &ubuf,
-					start, end);
-	if (ret)
-		goto out;
+	user_regset_copyin_ignore(&pos, &count, &kbuf, &ubuf, start, end);
 
 	/*
 	 * Copy fpsr, and fpcr which must follow contiguously in
-- 
2.26.3