From patchwork Wed Mar 5 22:39:04 2025 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Zhaoming Luo X-Patchwork-Id: 107413 Return-Path: X-Original-To: patchwork@sourceware.org Delivered-To: patchwork@sourceware.org Received: from server2.sourceware.org (localhost [IPv6:::1]) by sourceware.org (Postfix) with ESMTP id 2581B3858D26 for ; Wed, 5 Mar 2025 22:40:14 +0000 (GMT) DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org 2581B3858D26 Authentication-Results: sourceware.org; dkim=pass (1024-bit key, unprotected) header.d=163.com header.i=@163.com header.a=rsa-sha256 header.s=s110527 header.b=C/ktSe7M X-Original-To: libc-alpha@sourceware.org Delivered-To: libc-alpha@sourceware.org Received: from m16.mail.163.com (m16.mail.163.com [220.197.31.5]) by sourceware.org (Postfix) with ESMTP id EF1933858D26 for ; Wed, 5 Mar 2025 22:39:35 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.4.2 sourceware.org EF1933858D26 Authentication-Results: sourceware.org; dmarc=pass (p=none dis=none) header.from=163.com Authentication-Results: sourceware.org; spf=pass smtp.mailfrom=163.com ARC-Filter: OpenARC Filter v1.0.0 sourceware.org EF1933858D26 Authentication-Results: server2.sourceware.org; arc=none smtp.remote-ip=220.197.31.5 ARC-Seal: i=1; a=rsa-sha256; d=sourceware.org; s=key; t=1741214376; cv=none; b=FbNcHb5EDGaN+6j2ZROhSvG1eUvg+vaFBGLbtG4puuZ3inUxq+ilxuOLAPnpRdnqyEp7c4a4nmMIaxq7Mzh4S30Jzxbr0t7tj1Pvpe8ua9KliMjwH71dh+z6iruuyt4FW30nh46m+0o4L3UFiOaU6qa1tZTNO6ELifFX8adM7XU= ARC-Message-Signature: i=1; a=rsa-sha256; d=sourceware.org; s=key; t=1741214376; c=relaxed/simple; bh=7yp/lU9dPy3J/CZwt1CByMljTcd0Cd8hsTP9b1l/o1U=; h=DKIM-Signature:From:To:Subject:Date:Message-ID:MIME-Version; b=kOmUVx0a50718KJKMEnqlcrahu7CJfjCxp0dknWvNrEsoqXDzxm4lqICnqOwJGW7U5OB5sNMpgGcMoipzoW/DsqEi1HVbdYgMoW0K5+FLWPa5aqpLNtslNfW7RD8/m1TLF/eEwLRykbuISPexbMapM4L1cBeX1sTGrLbqHSChiE= ARC-Authentication-Results: i=1; server2.sourceware.org DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org EF1933858D26 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=163.com; s=s110527; h=From:Subject:Date:Message-ID:MIME-Version; bh=czrYI m7qBbvNZDQZFlvzRvi/hpNMnQZiKLOqvH4lV8k=; b=C/ktSe7Mc4pHYpwwbhhb5 HlEGKgPTtEzOv74vnIKo5NtZbGWGhMm13Ze7plDIWvSYEXxkn04K5p0nxus4bMTH jQKlf4fT1gymh+CYiYv5M2SYOt69+cAJ5/mHgekf4n8XbyMGyYUaMAJ7ymQzZ4HD iRubMJP3dpS5Z7du0RolT8= Received: from localhost.localdomain (unknown []) by gzsmtp3 (Coremail) with SMTP id PigvCgCH_haI0shn05frCw--.2092S2; Thu, 06 Mar 2025 06:39:16 +0800 (CST) From: Zhaoming Luo To: libc-alpha@sourceware.org Cc: samuel.thibault@gnu.org, bug-hurd@gnu.org, Zhaoming Luo Subject: [PATCH] hurd: Check return value of mach_port_mod_refs() in the dup routine of fcntl() Date: Thu, 6 Mar 2025 06:39:04 +0800 Message-ID: <20250305223904.9108-1-zhmingluo@163.com> X-Mailer: git-send-email 2.47.2 MIME-Version: 1.0 X-CM-TRANSID: PigvCgCH_haI0shn05frCw--.2092S2 X-Coremail-Antispam: 1Uf129KBjvJXoW7KF47Zw1DtFyUCrW3Jr1fZwb_yoW8Cw45p3 W3Cws8KrZ8ZayvqFs3Wa4vvan5Ca1rJ34UZFy3Kr1xAFW5ZrWrWr42kF9a9rWUZF97A3y5 JFZ8GFW3Ww4UZr7anT9S1TB71UUUUU7qnTZGkaVYY2UrUUUUjbIjqfuFe4nvWSU5nxnvy2 9KBjDUYxBIdaVFxhVjvjDU0xZFpf9x0pR1SoLUUUUU= X-Originating-IP: [223.104.69.115] X-CM-SenderInfo: p2kpx0pjox0qqrwthudrp/1tbiSgkHLGfIxWplBAABsI X-Spam-Status: No, score=-13.1 required=5.0 tests=BAYES_00, DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, DKIM_VALID_EF, FREEMAIL_FROM, GIT_PATCH_0, RCVD_IN_DNSWL_NONE, RCVD_IN_MSPIKE_H2, SPF_HELO_NONE, SPF_PASS, TXREP, UNPARSEABLE_RELAY autolearn=ham autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on server2.sourceware.org X-BeenThere: libc-alpha@sourceware.org X-Mailman-Version: 2.1.30 Precedence: list List-Id: Libc-alpha mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: libc-alpha-bounces~patchwork=sourceware.org@sourceware.org Ignoring the return value of mach_port_mod_ref() causes the situation that when the reference count of the io server port is full, the caller of dup() still supposes a new file discriptor is allocated. In this patch we check the return value of mach_port_mod_ref() and return an error when it fails. Signed-off-by: Zhaoming Luo --- sysdeps/mach/hurd/fcntl.c | 38 +++++++++++++++++++++++++++----------- 1 file changed, 27 insertions(+), 11 deletions(-) diff --git a/sysdeps/mach/hurd/fcntl.c b/sysdeps/mach/hurd/fcntl.c index a65c190c..d97226cd 100644 --- a/sysdeps/mach/hurd/fcntl.c +++ b/sysdeps/mach/hurd/fcntl.c @@ -83,18 +83,34 @@ __libc_fcntl (int fd, int cmd, ...) result = -1; else { - /* Give the ports each a user ref for the new descriptor. */ - __mach_port_mod_refs (__mach_task_self (), port, + /* Give the ports (i.e. `ctty` and `port`) each a user ref for + the new descriptor. */ + err = __mach_port_mod_refs (__mach_task_self (), port, MACH_PORT_RIGHT_SEND, 1); - if (ctty != MACH_PORT_NULL) - __mach_port_mod_refs (__mach_task_self (), ctty, - MACH_PORT_RIGHT_SEND, 1); - - /* Install the ports and flags in the new descriptor. */ - if (ctty != MACH_PORT_NULL) - _hurd_port_set (&new->ctty, ctty); - new->flags = flags; - _hurd_port_locked_set (&new->port, port); /* Unlocks NEW. */ + + if (err) + { + /* When an error occurs during giving a user ref to the + io server port */ + result = -1; + + if (err == KERN_UREFS_OVERFLOW) + errno = EMFILE; + else + errno = EINVAL; + } + else + { + if (ctty != MACH_PORT_NULL) + __mach_port_mod_refs (__mach_task_self (), ctty, + MACH_PORT_RIGHT_SEND, 1); + + /* Install the ports and flags in the new descriptor. */ + if (ctty != MACH_PORT_NULL) + _hurd_port_set (&new->ctty, ctty); + new->flags = flags; + _hurd_port_locked_set (&new->port, port); /* Unlocks NEW. */ + } } HURD_CRITICAL_END;