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 26259358A9; Mon, 11 Dec 2023 13:57:39 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="V374Q210" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 06E69C433C9; Mon, 11 Dec 2023 13:57:37 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1702303059; bh=gmWXl8OnCsDxGnfCAvvdJ9/lz1xt84JHADheam84Pw0=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=V374Q210qweBD3E8fXjl1CBQBikPTEb7Kz6PJdJC36Zcckw50tE9/yRhcFF0BFqdF zu0Gx1qAfPHR4FyqcD9HT93uQBZAgrUei1mt1Q1B/GqPeBLorMfwYWQz0q77iXy/p+ SbS71XArMz88bAK2DMsjBEs2oNPn6C/v883SmFYuopOuVHdUl1TSQ82EY/5kb6DsNx 4zqTvAn8dKZkAK7zSddzozfAKt15ZKEjoNwSEtMmQqpMR8CjyMhET9GE5lbJoOSU9K +xDjyUBaWyyiPT8mcbkAcVy04d732RcMlxfu7qJiNrbUozcWIK7XvpduGJxbNmujD/ 3F0QBPgBb6FIw== From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Hengqi Chen , Huacai Chen , Sasha Levin , chenhuacai@kernel.org, yangtiezhu@loongson.cn, loongarch@lists.linux.dev, linux-mm@kvack.org Subject: [PATCH AUTOSEL 6.1 29/29] LoongArch: Preserve syscall nr across execve() Date: Mon, 11 Dec 2023 08:54:13 -0500 Message-ID: <20231211135457.381397-29-sashal@kernel.org> X-Mailer: git-send-email 2.42.0 In-Reply-To: <20231211135457.381397-1-sashal@kernel.org> References: <20231211135457.381397-1-sashal@kernel.org> Precedence: bulk X-Mailing-List: loongarch@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore X-stable-base: Linux 6.1.66 Content-Transfer-Encoding: 8bit From: Hengqi Chen [ Upstream commit d6c5f06e46a836e6a70c7cfd95bb38a67d9252ec ] Currently, we store syscall nr in pt_regs::regs[11] and syscall execve() accidentally overrides it during its execution: sys_execve() -> do_execve() -> do_execveat_common() -> bprm_execve() -> exec_binprm() -> search_binary_handler() -> load_elf_binary() -> ELF_PLAT_INIT() ELF_PLAT_INIT() reset regs[11] to 0, so in syscall_exit_to_user_mode() we later get a wrong syscall nr. This breaks tools like execsnoop since it relies on execve() tracepoints. Skip pt_regs::regs[11] reset in ELF_PLAT_INIT() to fix the issue. Signed-off-by: Hengqi Chen Signed-off-by: Huacai Chen Signed-off-by: Sasha Levin --- arch/loongarch/include/asm/elf.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/arch/loongarch/include/asm/elf.h b/arch/loongarch/include/asm/elf.h index b9a4ab54285c1..9b16a3b8e7060 100644 --- a/arch/loongarch/include/asm/elf.h +++ b/arch/loongarch/include/asm/elf.h @@ -293,7 +293,7 @@ extern const char *__elf_platform; #define ELF_PLAT_INIT(_r, load_addr) do { \ _r->regs[1] = _r->regs[2] = _r->regs[3] = _r->regs[4] = 0; \ _r->regs[5] = _r->regs[6] = _r->regs[7] = _r->regs[8] = 0; \ - _r->regs[9] = _r->regs[10] = _r->regs[11] = _r->regs[12] = 0; \ + _r->regs[9] = _r->regs[10] /* syscall n */ = _r->regs[12] = 0; \ _r->regs[13] = _r->regs[14] = _r->regs[15] = _r->regs[16] = 0; \ _r->regs[17] = _r->regs[18] = _r->regs[19] = _r->regs[20] = 0; \ _r->regs[21] = _r->regs[22] = _r->regs[23] = _r->regs[24] = 0; \ -- 2.42.0