From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id BF08A8BE0 for ; Tue, 28 Mar 2023 15:01:48 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 3FDBDC433D2; Tue, 28 Mar 2023 15:01:48 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1680015708; bh=wIMMwK89KStOb42+4eP014hy8v2pJD2GJYpw7okucq8=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=QnVWHrKQElEzFPoBi+S7+X2sC0L13pLFuj25kW5KQRl7O2aL/PAo9IXdjC54GzmIj Mg8lBZVo78twTwZaQJL5iJOC8zMFdU1G39vkf/99w7rSxhQDsDBiuQHXEBdwPoTnyz WBA0X2hwME5X/JKUJp9AFYQwvkUfUw0VZvouO3to= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Al Viro , Rich Felker , Linus Torvalds , Sasha Levin Subject: [PATCH 6.1 145/224] sh: sanitize the flags on sigreturn Date: Tue, 28 Mar 2023 16:42:21 +0200 Message-Id: <20230328142623.414652645@linuxfoundation.org> X-Mailer: git-send-email 2.40.0 In-Reply-To: <20230328142617.205414124@linuxfoundation.org> References: <20230328142617.205414124@linuxfoundation.org> User-Agent: quilt/0.67 Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit From: Al Viro [ Upstream commit 573b22ccb7ce9ab7f0539a2e11a9d3609a8783f5 ] We fetch %SR value from sigframe; it might have been modified by signal handler, so we can't trust it with any bits that are not modifiable in user mode. Signed-off-by: Al Viro Cc: Rich Felker Signed-off-by: Linus Torvalds Signed-off-by: Sasha Levin --- arch/sh/include/asm/processor_32.h | 1 + arch/sh/kernel/signal_32.c | 3 +++ 2 files changed, 4 insertions(+) diff --git a/arch/sh/include/asm/processor_32.h b/arch/sh/include/asm/processor_32.h index 27aebf1e75a20..3ef7adf739c83 100644 --- a/arch/sh/include/asm/processor_32.h +++ b/arch/sh/include/asm/processor_32.h @@ -50,6 +50,7 @@ #define SR_FD 0x00008000 #define SR_MD 0x40000000 +#define SR_USER_MASK 0x00000303 // M, Q, S, T bits /* * DSP structure and data */ diff --git a/arch/sh/kernel/signal_32.c b/arch/sh/kernel/signal_32.c index 90f495d35db29..a6bfc6f374911 100644 --- a/arch/sh/kernel/signal_32.c +++ b/arch/sh/kernel/signal_32.c @@ -115,6 +115,7 @@ static int restore_sigcontext(struct pt_regs *regs, struct sigcontext __user *sc, int *r0_p) { unsigned int err = 0; + unsigned int sr = regs->sr & ~SR_USER_MASK; #define COPY(x) err |= __get_user(regs->x, &sc->sc_##x) COPY(regs[1]); @@ -130,6 +131,8 @@ restore_sigcontext(struct pt_regs *regs, struct sigcontext __user *sc, int *r0_p COPY(sr); COPY(pc); #undef COPY + regs->sr = (regs->sr & SR_USER_MASK) | sr; + #ifdef CONFIG_SH_FPU if (boot_cpu_data.flags & CPU_HAS_FPU) { int owned_fp; -- 2.39.2