From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.remote-ip=100.103.45.18 ARC-Seal: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=none; t=1794590336; b=mruGrCCa3E1v+EUVyFM9vZjFgWxC/bonBsDT71bl+eWvdapaeaNGEzVshe2956k6Mg5j aS4CHjfdR3QUWfVhVnvlYUci65+9G/mxiLlihU1hV3AktH4+HBvrWJP8rldgFy3NEuskQ 90kTtB6ppyG1dcp6oKPwg/F0OEZrzFe3oxwxfd5KX92MCpaiKrxRj2SwTPsh0SwWpiLjl 3d2TYFuT/rBBEguAF+ROu1sxG1wfMt+DQSqLJbluDn/9ZLF+nighKBhEx16fYXsO43uwo i2joerv9KeEwAj6k7uiZHBzlvqbTEIzD3QmH73EpkCcljy4i2HxGvB1TCure0lGsnmg== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1794590336; h=Received:DKIM-Signature:From:To:Cc:Subject:Date:Message-ID:X-Mailer: In-Reply-To:References:User-Agent:X-stable:X-Patchwork-Hint: MIME-Version:Content-Type:Content-Transfer-Encoding; bh=NzMPwbKH67/SDhMULMYvgAu4v6WhjfSLl3KF5qk1IfA=; b=qGMFJJOfbCQYJKVpvbmOCs7D6yAOJKvbqRUH3ysOnfrI7+CH9Af24BQPAKYnqJCZjdiS 0FMXelcx1Trff9r9TroAEs3DX+PJvZDz6Y/fdFlXYkHhF6AxVasJj1AtQ6HJaKkC9pSYm G8gqcd/dxk1I2X3gYVEMgISfcVqrI/eZtD+FRQTR3NoTzdN+rgYy73ZbGTbE/IVxVGVpz EV7cFzuhhCEuptLBKaboLGAxOd2kUu9HdnG6/C+rY4AdRi6IwwwkWqag7+vfBqOUqtFBM mL+Gx336RxUdZpaJIFUufRDWO4V6EuV9GA3oI4WsKQn/XWnVQJ/oPhLvfOm+tDpxkKQ== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass header.d=linuxfoundation.org header.i=@linuxfoundation.org header.a=rsa-sha256 header.s=korg header.b=WmpyMROg; arc=none smtp.remote-ip=100.103.45.18 Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (prime256v1)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id B0D3F606D87A; Fri, 13 Nov 2026 17:18:56 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.a=rsa-sha256 header.s=korg header.b=WmpyMROg Received: by smtp.kernel.org (Postfix) with ESMTPSA id 630011F000C6; Fri, 13 Nov 2026 17:18:56 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1794590336; bh=NzMPwbKH67/SDhMULMYvgAu4v6WhjfSLl3KF5qk1IfA=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=WmpyMROgjKGENJbHfalnILtGQ2F0sAhN2GZVX2d/o7Sn+fb00a+xaM7C/w4twB2Nt K7XeJW48/wrsFc6NRT5XH2SXmFxqnm0U4TaHiKpiSb0llpEq7wTKv7rFz4pYW6UJWO rVK6R42O/PadsQrppviFsOY2hB94izmI/4zZ8EF0= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Hengyu Liang , Andrew Morton , "David Hildenbrand (Arm)" , Pedro Falcato , "Lorenzo Stoakes (ARM)" , "Liam R. Howlett" , Vlastimil Babka , Jann Horn , Muhammad Usama Anjum , Andrei Vagin , =?UTF-8?q?Micha=C5=82=20Miros=C5=82aw?= , Arnd Bergmann , Sasha Levin Subject: [PATCH 6.18 314/686] fs/proc/task_mmu: return -ENOTTY for unknown pagemap ioctls Date: Fri, 13 Nov 2026 10:47:27 -0500 Message-ID: <20261113153831.581415803@linuxfoundation.org> X-Mailer: git-send-email 2.56.0 In-Reply-To: <20261113153820.902362109@linuxfoundation.org> References: <20261113153820.902362109@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore X-Mailing-List: patches@lists.linux.dev List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit 6.18-stable review patch. If anyone has any objections, please let me know. ------------------ From: Hengyu Liang [ Upstream commit bfc1d9724c78aa7570dbeb17207a21089f2d1b1a ] Commit 52526ca7fdb9 ("fs/proc/task_mmu: implement IOCTL to get and optionally clear info about PTEs") made do_pagemap_cmd() the ioctl handler of /proc//pagemap. However, do_pagemap_cmd() returns -EINVAL for every command other than PAGEMAP_SCAN. Before that commit, pagemap had no ioctl handler, and the VFS returned -ENOTTY for these commands. As of now, they fail with EINVAL, so tcgetattr() and isatty() on pagemap report EINVAL instead of ENOTTY. The issue can be reproduced with a simple C program: #include #include #include int main(void) { struct termios t; int fd = open("/proc/self/pagemap", O_RDONLY); if (tcgetattr(fd, &t) < 0) perror("tcgetattr"); return 0; } Before that commit, the result is: tcgetattr: Inappropriate ioctl for device After that commit, the result is: tcgetattr: Invalid argument This patch will return -ENOIOCTLCMD for unknown commands, as procfs_procmap_ioctl() in the same file does, so that the VFS turns it into -ENOTTY. Link: https://lore.kernel.org/20261023181300.3366487-1-hengyul@cs.unc.edu Fixes: 52526ca7fdb9 ("fs/proc/task_mmu: implement IOCTL to get and optionally clear info about PTEs") Signed-off-by: Hengyu Liang Signed-off-by: Andrew Morton Acked-by: David Hildenbrand (Arm) Reviewed-by: Pedro Falcato Reviewed-by: Lorenzo Stoakes (ARM) Cc: Liam R. Howlett Cc: Vlastimil Babka Cc: Jann Horn Cc: Muhammad Usama Anjum Cc: Andrei Vagin Cc: Michał Mirosław Cc: Arnd Bergmann Cc: Signed-off-by: Sasha Levin --- fs/proc/task_mmu.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/fs/proc/task_mmu.c b/fs/proc/task_mmu.c index 0f08913cfa529..823e8ee1b0953 100644 --- a/fs/proc/task_mmu.c +++ b/fs/proc/task_mmu.c @@ -3179,7 +3179,7 @@ static long do_pagemap_cmd(struct file *file, unsigned int cmd, return do_pagemap_scan(mm, arg); default: - return -EINVAL; + return -ENOIOCTLCMD; } } -- 2.53.0