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=1793631978; b=dMgULE0OwxbLn2wh4En+gm3gPL4xrg28TuH5dsmYHQKZ2Kk0U5w3baApO/FEKiB3Dqxc 13Znm+Jtb7+2bkBOP1yxXkqdP8ZagWyEmU1egwK9UBsdtGiaGV7rY48TLNnQlq71KOEhw CnopgNiuz4rp03D6eVyqJ4ezIqLKJ52i4wptiaBaAtKvVF0zFksHzucrOMxJmUusJz/rI Fm/j+ugOb54pPuQZsto5iTk1pimkaY50YOsI6eeYfevWgYA6hoZI5s2SMeXN2Nb/rGQUv sZyfgzJSEejgMJtlJZaKks7+h0QKocdGByriU2LZUrALbSrOTkc38bf6iLTjMZDnOJg== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1793631978; h=Received:DKIM-Signature:From:Date:Subject:MIME-Version:Content-Type: Content-Transfer-Encoding:Message-Id:References:In-Reply-To:To:Cc: X-Mailer; bh=OLir7M9bUqyYwhZJ8zktlBEIF8q4TgFqxNnhzWbUGpI=; b=zYXTm3LdT/xNB1jYbxooXwftDFJsUmkqjNleUFU7KArQAQAHtiKBONMIYHroCE3iVv4g 4MAKo8JFBcseLp4XlaZHwEQ183lYBQsHXfICLh5XNt1ecdnADwEN9LrCqyFkufpyMOz9X ooiIIgawGjt7CaDm1DzuOrWEAVWzPz8xqw68Y6qO56GIGtfftFH8STv4EHmO5AOh6nqkd BfOq7ZKtGCGGCYK7tqFEeRAbebskqW7kAKLej4a4hssAIGc41uDss9uf/dc8KncLy9ypV 5+C9KYdnMKqlDaLMwtEYvfjZCXFwdhJEUduxuWIiAWBGq1KTtQ9ZioeB4hZ15g1CrLA== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b=DXh2wTXC; 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 4593D60722A3; Mon, 2 Nov 2026 15:06:18 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key, unprotected) header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b=DXh2wTXC Received: by smtp.kernel.org (Postfix) with ESMTPSA id 46D671F00A18; Mon, 2 Nov 2026 15:05:59 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1793631977; bh=OLir7M9bUqyYwhZJ8zktlBEIF8q4TgFqxNnhzWbUGpI=; h=From:Date:Subject:References:In-Reply-To:To:Cc; b=DXh2wTXC5VH77hnNnBlykaDhaUktPNfk5KXDpgV/7gXuYGd3odp2PAnlkIjkJcfwQ o9sxUl0dG/poWSGN79w2hy79MhM+2ztMpCOszGkOriShPgsszxRZ3ZRol64cXOqv2A 8eMmQU21JeKaxaR8/PkbA3dv0fEzY8Yy9ptwbGLqD9ZhBkx9YpAOAdrNHRRRoTVx07 W+r1ujTQggO56FKWxnPRth4ymfmLY/JbPNj9rdkw26qWgcW6WoX2cQIQ4o12qUFDB+ qh+O9CiaFL8rKOi7/exZPrc7xKe5i7H2dzyzLS2B7MYRkTDDfrAkgu/6EfP23mzFom VD4IVD7SeTZBQ== From: Christian Brauner Date: Mon, 02 Nov 2026 16:01:41 +0100 Subject: [PATCH RFC 14/22] x86/mtrr: let procfs copy the ioctl arguments of /proc/mtrr X-Mailing-List: linux-modules@vger.kernel.org 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: 7bit Message-Id: <20261102-work-procfs-arch-v1-14-c9492ab08480@kernel.org> References: <20261102-work-procfs-arch-v1-0-c9492ab08480@kernel.org> In-Reply-To: <20261102-work-procfs-arch-v1-0-c9492ab08480@kernel.org> To: linux-fsdevel@vger.kernel.org Cc: Linus Torvalds , Jann Horn , Josef Bacik , Chris Mason , Jeff Layton , NeilBrown , Eric Dumazet , Thomas Gleixner , Al Viro , Jonathan Corbet , Christoph Hellwig , Greg Kroah-Hartman , Joel Granados , Kees Cook , Jan Kara , Jan Kara , linux-kernel@vger.kernel.org, linux-nfs@vger.kernel.org, linux-acpi@vger.kernel.org, linux-kselftest@vger.kernel.org, linux-s390@vger.kernel.org, linux-scsi@vger.kernel.org, linux-um@lists.infradead.org, linux-wireless@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, netdev@vger.kernel.org, ntfs3@lists.linux.dev, platform-driver-x86@vger.kernel.org, coreteam@netfilter.org, kexec@lists.infradead.org, linux-pci@vger.kernel.org, linux-sound@vger.kernel.org, netfilter-devel@vger.kernel.org, dri-devel@lists.freedesktop.org, ibm-acpi-devel@lists.sourceforge.net, jfs-discussion@lists.sourceforge.net, linux-alpha@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-cifs@vger.kernel.org, linux-fbdev@vger.kernel.org, linux-hwmon@vger.kernel.org, linux-mm@kvack.org, linux-sh@vger.kernel.org, linux-usb@vger.kernel.org, samba-technical@lists.samba.org, sparclinux@vger.kernel.org, linux-m68k@lists.linux-m68k.org, linux-doc@vger.kernel.org, linux-serial@vger.kernel.org, linux-atm-general@lists.sourceforge.net, Takashi Iwai , linux-input@vger.kernel.org, linux-raid@vger.kernel.org, linux-ext4@vger.kernel.org, linux-modules@vger.kernel.org, linux-debuggers@vger.kernel.org, "Christian Brauner (Amutable)" , Chuck Lever X-Mailer: b4 0.17-dev Implement ->proc_ioctl_buf() so procfs copies the arguments in before it pins the entry and back out after unpinning it. The native and the 32-bit commands encode their arguments and share one table. mtrr_ioctl() reads and fills procfs' copy, also in the 32-bit layouts. Signed-off-by: Christian Brauner (Amutable) --- arch/x86/kernel/cpu/mtrr/if.c | 79 +++++++++++++++++++++++++------------------ 1 file changed, 46 insertions(+), 33 deletions(-) diff --git a/arch/x86/kernel/cpu/mtrr/if.c b/arch/x86/kernel/cpu/mtrr/if.c index 038e2dc38797..9c33c0428dfe 100644 --- a/arch/x86/kernel/cpu/mtrr/if.c +++ b/arch/x86/kernel/cpu/mtrr/if.c @@ -149,7 +149,7 @@ mtrr_write(struct file *file, char *buf, size_t len, loff_t * ppos) } static long -mtrr_ioctl(struct file *file, unsigned int cmd, unsigned long __arg) +mtrr_ioctl(struct file *file, unsigned int cmd, void *arg) { int err = 0; mtrr_type type; @@ -157,7 +157,6 @@ mtrr_ioctl(struct file *file, unsigned int cmd, unsigned long __arg) unsigned long size; struct mtrr_sentry sentry; struct mtrr_gentry gentry; - void __user *arg = (void __user *) __arg; memset(&gentry, 0, sizeof(gentry)); @@ -170,13 +169,11 @@ mtrr_ioctl(struct file *file, unsigned int cmd, unsigned long __arg) case MTRRIOC_SET_PAGE_ENTRY: case MTRRIOC_DEL_PAGE_ENTRY: case MTRRIOC_KILL_PAGE_ENTRY: - if (copy_from_user(&sentry, arg, sizeof(sentry))) - return -EFAULT; + memcpy(&sentry, arg, sizeof(sentry)); break; case MTRRIOC_GET_ENTRY: case MTRRIOC_GET_PAGE_ENTRY: - if (copy_from_user(&gentry, arg, sizeof(gentry))) - return -EFAULT; + memcpy(&gentry, arg, sizeof(gentry)); break; #ifdef CONFIG_COMPAT case MTRRIOC32_ADD_ENTRY: @@ -187,27 +184,21 @@ mtrr_ioctl(struct file *file, unsigned int cmd, unsigned long __arg) case MTRRIOC32_SET_PAGE_ENTRY: case MTRRIOC32_DEL_PAGE_ENTRY: case MTRRIOC32_KILL_PAGE_ENTRY: { - struct mtrr_sentry32 __user *s32; + struct mtrr_sentry32 *s32 = arg; - s32 = (struct mtrr_sentry32 __user *)__arg; - err = get_user(sentry.base, &s32->base); - err |= get_user(sentry.size, &s32->size); - err |= get_user(sentry.type, &s32->type); - if (err) - return err; + sentry.base = s32->base; + sentry.size = s32->size; + sentry.type = s32->type; break; } case MTRRIOC32_GET_ENTRY: case MTRRIOC32_GET_PAGE_ENTRY: { - struct mtrr_gentry32 __user *g32; + struct mtrr_gentry32 *g32 = arg; - g32 = (struct mtrr_gentry32 __user *)__arg; - err = get_user(gentry.regnum, &g32->regnum); - err |= get_user(gentry.base, &g32->base); - err |= get_user(gentry.size, &g32->size); - err |= get_user(gentry.type, &g32->type); - if (err) - return err; + gentry.regnum = g32->regnum; + gentry.base = g32->base; + gentry.size = g32->size; + gentry.type = g32->type; break; } #endif @@ -312,19 +303,17 @@ mtrr_ioctl(struct file *file, unsigned int cmd, unsigned long __arg) switch (cmd) { case MTRRIOC_GET_ENTRY: case MTRRIOC_GET_PAGE_ENTRY: - if (copy_to_user(arg, &gentry, sizeof(gentry))) - err = -EFAULT; + memcpy(arg, &gentry, sizeof(gentry)); break; #ifdef CONFIG_COMPAT case MTRRIOC32_GET_ENTRY: case MTRRIOC32_GET_PAGE_ENTRY: { - struct mtrr_gentry32 __user *g32; + struct mtrr_gentry32 *g32 = arg; - g32 = (struct mtrr_gentry32 __user *)__arg; - err = put_user(gentry.base, &g32->base); - err |= put_user(gentry.size, &g32->size); - err |= put_user(gentry.regnum, &g32->regnum); - err |= put_user(gentry.type, &g32->type); + g32->base = gentry.base; + g32->size = gentry.size; + g32->regnum = gentry.regnum; + g32->type = gentry.type; break; } #endif @@ -393,14 +382,38 @@ static int mtrr_open(struct inode *inode, struct file *file) return 0; } +static const struct proc_ioctl_arg mtrr_ioctl_args[] = { + PROC_IOCTL_IOC(MTRRIOC_ADD_ENTRY), + PROC_IOCTL_IOC(MTRRIOC_SET_ENTRY), + PROC_IOCTL_IOC(MTRRIOC_DEL_ENTRY), + PROC_IOCTL_IOC(MTRRIOC_GET_ENTRY), + PROC_IOCTL_IOC(MTRRIOC_KILL_ENTRY), + PROC_IOCTL_IOC(MTRRIOC_ADD_PAGE_ENTRY), + PROC_IOCTL_IOC(MTRRIOC_SET_PAGE_ENTRY), + PROC_IOCTL_IOC(MTRRIOC_DEL_PAGE_ENTRY), + PROC_IOCTL_IOC(MTRRIOC_GET_PAGE_ENTRY), + PROC_IOCTL_IOC(MTRRIOC_KILL_PAGE_ENTRY), +#ifdef CONFIG_COMPAT + PROC_IOCTL_IOC(MTRRIOC32_ADD_ENTRY), + PROC_IOCTL_IOC(MTRRIOC32_SET_ENTRY), + PROC_IOCTL_IOC(MTRRIOC32_DEL_ENTRY), + PROC_IOCTL_IOC(MTRRIOC32_GET_ENTRY), + PROC_IOCTL_IOC(MTRRIOC32_KILL_ENTRY), + PROC_IOCTL_IOC(MTRRIOC32_ADD_PAGE_ENTRY), + PROC_IOCTL_IOC(MTRRIOC32_SET_PAGE_ENTRY), + PROC_IOCTL_IOC(MTRRIOC32_DEL_PAGE_ENTRY), + PROC_IOCTL_IOC(MTRRIOC32_GET_PAGE_ENTRY), + PROC_IOCTL_IOC(MTRRIOC32_KILL_PAGE_ENTRY), +#endif +}; + static const struct proc_ops mtrr_proc_ops = { .proc_show = mtrr_seq_show, .proc_open = mtrr_open, .proc_write_buf = mtrr_write, - .proc_ioctl = mtrr_ioctl, -#ifdef CONFIG_COMPAT - .proc_compat_ioctl = mtrr_ioctl, -#endif + .proc_ioctl_buf = mtrr_ioctl, + .proc_ioctl_args = mtrr_ioctl_args, + .proc_nr_ioctl_args = ARRAY_SIZE(mtrr_ioctl_args), .proc_release = mtrr_close, }; -- 2.53.0