From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (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 7E89D29D288; Sat, 12 Sep 2026 19:55:30 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789242931; cv=none; b=a5leA5s4qaoQiDUiY0ZGutpzX7XsMHGHrNQbvsSTst1mMZSx4xC0J51lIQUFlMo9kyT3z2QKZ0J0GSo6MgITx5CYCpNwgTS46hMx9FAnzb2zzgi5EjNtAzYdA90BrFV5hCbgUYAUvwsHqbNZhtv8NzCSGu6hWbhBpQN92I9VMZU= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789242931; c=relaxed/simple; bh=AeZ8lZPnD4d2j88Q7yghDS4ME3j/8goN36Bq4Hr2oyw=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=rLIXQUH6ovdDqkBuT3X7XBsdP21d/XJGd9NBzEgmCEqhQ5Z4sCnBiITaXzPVp8oKuqKonA8/n38auQfbc42HdOzBdAscCTYQSyTvrrzRQIZ0pLQuf/nUFWlrPFJUXY5B274wVho33nPBtLS4HUi1ULG+349RphXzNQi2Wf0x3xY= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=WHeYHKtw; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="WHeYHKtw" Received: by smtp.kernel.org (Postfix) with ESMTPSA id D6C891F000FF; Sat, 12 Sep 2026 19:55:29 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1789242930; bh=ClbuJUklhgpys+SQ6fRorm1USDx1jAarisbl4cBMtPY=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=WHeYHKtwsohtsGlYHqsf17oKSNIIY/KO2u0g7DHHpNstJWnWu5ElgFw1AvgaNl99Z 8JYHQ6dUDvwXxs+JOWJxjwwYc8np/ZEXZYMRL1HMIKIM9iPSrEBg1LUktXNAEqvMrd x7Sh3IpF8aXaaYV/a4enJNRCY0PHd0bKCiymgLFo= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, =?UTF-8?q?Philippe=20Mathieu-Daud=C3=A9?= , Thomas Bogendoerfer , Sasha Levin Subject: [PATCH 5.10 577/798] MIPS: ptrace: Fix syscall skipping via PTRACE_SYSCALL Date: Sat, 12 Sep 2026 09:03:25 +0200 Message-ID: <20260912065530.356164540@linuxfoundation.org> X-Mailer: git-send-email 2.55.0 In-Reply-To: <20260912065516.948645775@linuxfoundation.org> References: <20260912065516.948645775@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore 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 5.10-stable review patch. If anyone has any objections, please let me know. ------------------ From: Thomas Bogendoerfer [ Upstream commit 5475c03fa25f31cfd5f8c7e552f8d10347bbaad9 ] If tracer wanted to skip a syscall return value was always overwritten with -ENOSYS. Fix this by checking against original syscall number and only return -ENOSYS, if it is negative. Fixes: b6318a903d06 ("MIPS/ptrace: Pick up ptrace/seccomp changed syscalls") Reviewed-by: Philippe Mathieu-Daudé Signed-off-by: Thomas Bogendoerfer Signed-off-by: Sasha Levin --- arch/mips/kernel/ptrace.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/arch/mips/kernel/ptrace.c b/arch/mips/kernel/ptrace.c index dd454b429ff73..d051d351e5a01 100644 --- a/arch/mips/kernel/ptrace.c +++ b/arch/mips/kernel/ptrace.c @@ -1312,8 +1312,12 @@ long arch_ptrace(struct task_struct *child, long request, */ asmlinkage long syscall_trace_enter(struct pt_regs *regs) { + long syscall; + user_exit(); + syscall = current_thread_info()->syscall; + if (test_thread_flag(TIF_SYSCALL_TRACE)) { if (tracehook_report_syscall_entry(regs)) return -1; @@ -1349,7 +1353,7 @@ asmlinkage long syscall_trace_enter(struct pt_regs *regs) * Negative syscall numbers are mistaken for rejected syscalls, but * won't have had the return value set appropriately, so we do so now. */ - if (current_thread_info()->syscall < 0) + if (syscall < 0) syscall_set_return_value(current, regs, -ENOSYS, 0); return current_thread_info()->syscall; } -- 2.53.0