From:   Greg Kroah-Hartman <gregkh@linuxfoundation.org>
To:     linux-kernel@vger.kernel.org
Cc:     Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        stable@vger.kernel.org, Helge Deller <deller@gmx.de>,
        Kyle McMartin <kyle@mcmartin.ca>
Subject: [PATCH 4.14 009/251] parisc: Fix ptrace check on syscall return
Date:   Wed, 24 Nov 2021 12:54:11 +0100
Message-Id: <20211124115710.536976895@linuxfoundation.org>
In-Reply-To: <20211124115710.214900256@linuxfoundation.org>
References: <20211124115710.214900256@linuxfoundation.org>
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From: Helge Deller <deller@gmx.de>

commit 8779e05ba8aaffec1829872ef9774a71f44f6580 upstream.

The TIF_XXX flags are stored in the flags field in the thread_info
struct (TI_FLAGS), not in the flags field of the task_struct structure
(TASK_FLAGS).

It seems this bug didn't generate any important side-effects, otherwise it
wouldn't have went unnoticed for 12 years (since v2.6.32).

Signed-off-by: Helge Deller <deller@gmx.de>
Fixes: ecd3d4bc06e48 ("parisc: stop using task->ptrace for {single,block}step flags")
Cc: Kyle McMartin <kyle@mcmartin.ca>
Cc: stable@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 arch/parisc/kernel/entry.S |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

--- a/arch/parisc/kernel/entry.S
+++ b/arch/parisc/kernel/entry.S
@@ -1849,7 +1849,7 @@ syscall_restore:
 	LDREG	TI_TASK-THREAD_SZ_ALGN-FRAME_SIZE(%r30),%r1
 
 	/* Are we being ptraced? */
-	ldw	TASK_FLAGS(%r1),%r19
+	LDREG	TI_FLAGS-THREAD_SZ_ALGN-FRAME_SIZE(%r30),%r19
 	ldi	_TIF_SYSCALL_TRACE_MASK,%r2
 	and,COND(=)	%r19,%r2,%r0
 	b,n	syscall_restore_rfi