{"id":2229047,"url":"http://patchwork.ozlabs.org/api/1.1/patches/2229047/?format=json","web_url":"http://patchwork.ozlabs.org/project/linuxppc-dev/patch/1a55107abe15dd78450888e2b5327c3a56af29b7.1777306795.git.chleroy@kernel.org/","project":{"id":2,"url":"http://patchwork.ozlabs.org/api/1.1/projects/2/?format=json","name":"Linux PPC development","link_name":"linuxppc-dev","list_id":"linuxppc-dev.lists.ozlabs.org","list_email":"linuxppc-dev@lists.ozlabs.org","web_url":"https://github.com/linuxppc/wiki/wiki","scm_url":"https://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux.git","webscm_url":"https://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux.git/"},"msgid":"<1a55107abe15dd78450888e2b5327c3a56af29b7.1777306795.git.chleroy@kernel.org>","date":"2026-04-27T17:13:47","name":"[RFC,v1,6/9] uaccess: Change copy_{to/from}_user to return -EFAULT","commit_ref":null,"pull_url":null,"state":"new","archived":false,"hash":"e26541c7cdaf18e829fa9e8f2302b9591f5754d9","submitter":{"id":92089,"url":"http://patchwork.ozlabs.org/api/1.1/people/92089/?format=json","name":"Christophe Leroy (CS GROUP)","email":"chleroy@kernel.org"},"delegate":null,"mbox":"http://patchwork.ozlabs.org/project/linuxppc-dev/patch/1a55107abe15dd78450888e2b5327c3a56af29b7.1777306795.git.chleroy@kernel.org/mbox/","series":[{"id":501691,"url":"http://patchwork.ozlabs.org/api/1.1/series/501691/?format=json","web_url":"http://patchwork.ozlabs.org/project/linuxppc-dev/list/?series=501691","date":"2026-04-27T17:13:41","name":"uaccess: Convert small fixed size copy_{to/from}_user() to scoped user access","version":1,"mbox":"http://patchwork.ozlabs.org/series/501691/mbox/"}],"comments":"http://patchwork.ozlabs.org/api/patches/2229047/comments/","check":"pending","checks":"http://patchwork.ozlabs.org/api/patches/2229047/checks/","tags":{},"headers":{"Return-Path":"\n ","X-Original-To":["incoming@patchwork.ozlabs.org","linuxppc-dev@lists.ozlabs.org"],"Delivered-To":"patchwork-incoming@legolas.ozlabs.org","Authentication-Results":["legolas.ozlabs.org;\n\tdkim=pass (2048-bit key;\n unprotected) header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256\n header.s=k20201202 header.b=YS9v5ort;\n\tdkim-atps=neutral","legolas.ozlabs.org;\n spf=pass (sender SPF authorized) smtp.mailfrom=lists.ozlabs.org\n (client-ip=112.213.38.117; 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lists.ozlabs.org;\n dmarc=pass (p=quarantine dis=none) header.from=kernel.org;\n dkim=pass (2048-bit key;\n unprotected) header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256\n header.s=k20201202 header.b=YS9v5ort; dkim-atps=neutral;\n spf=pass (client-ip=172.234.252.31; helo=sea.source.kernel.org;\n envelope-from=chleroy@kernel.org;\n receiver=lists.ozlabs.org) smtp.mailfrom=kernel.org","DKIM-Signature":"v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org;\n\ts=k20201202; t=1777310325;\n\tbh=x+yz+Ptlr8yUKihbRCrYsj2OzN4+HDHdWj3mTkeeywo=;\n\th=From:To:Cc:Subject:Date:In-Reply-To:References:From;\n\tb=YS9v5orti9jIm2coPKy7cH4iQCLjTYOH2T4kGrmAKw1lk2UpD8UcWDut4XHtMo5CX\n\t 290KHU3PNOVzMmnTKEL1o/OfzgOnzBVsJnbuGicRbc3HqjVsrjLo1DZ4Ncwz6tafWZ\n\t SG8/hG1Ct8pUgSHrDrW4chwaJ34uCldA2tlOQo4bI8M4kMxsW5bP0OLNOAC7BeTwPk\n\t Mil/pgBJA2/iCGWwmbEh5WNZZrQ4Md/gtqmnREocwFdhobkWjiqhIB30lRO/GV15k3\n\t DZOePxOSt4vdcYmGqKSVWX7R1FegGyxqEmqkjMUEcFWkKzHsBpXNo8/6bbP3EGANbq\n\t KZwGUUWEURiLg==","From":"\"Christophe Leroy (CS GROUP)\" ","To":"Yury Norov ,\n\tAndrew Morton ,\n\tLinus Torvalds ,\n\tDavid Laight ,\n\tThomas Gleixner ","Cc":"\"Christophe Leroy (CS GROUP)\" ,\n\tlinux-alpha@vger.kernel.org,\n\tlinux-kernel@vger.kernel.org,\n\tlinux-snps-arc@lists.infradead.org,\n\tlinux-arm-kernel@lists.infradead.org,\n\tlinux-mips@vger.kernel.org,\n\tlinuxppc-dev@lists.ozlabs.org,\n\tkvm@vger.kernel.org,\n\tlinux-riscv@lists.infradead.org,\n\tlinux-s390@vger.kernel.org,\n\tsparclinux@vger.kernel.org,\n\tlinux-um@lists.infradead.org,\n\tdmaengine@vger.kernel.org,\n\tlinux-efi@vger.kernel.org,\n\tlinux-fsi@lists.ozlabs.org,\n\tamd-gfx@lists.freedesktop.org,\n\tdri-devel@lists.freedesktop.org,\n\tintel-gfx@lists.freedesktop.org,\n\tlinux-wpan@vger.kernel.org,\n\tnetdev@vger.kernel.org,\n\tlinux-wireless@vger.kernel.org,\n\tlinux-spi@vger.kernel.org,\n\tlinux-media@vger.kernel.org,\n\tlinux-staging@lists.linux.dev,\n\tlinux-serial@vger.kernel.org,\n\tlinux-usb@vger.kernel.org,\n\txen-devel@lists.xenproject.org,\n\tlinux-fsdevel@vger.kernel.org,\n\tocfs2-devel@lists.linux.dev,\n\tbpf@vger.kernel.org,\n\tkasan-dev@googlegroups.com,\n\tlinux-mm@kvack.org,\n\tlinux-x25@vger.kernel.org,\n\trust-for-linux@vger.kernel.org,\n\tlinux-sound@vger.kernel.org,\n\tsound-open-firmware@alsa-project.org,\n\tlinux-csky@vger.kernel.org,\n\tlinux-hexagon@vger.kernel.org,\n\tloongarch@lists.linux.dev,\n\tlinux-m68k@lists.linux-m68k.org,\n\tlinux-openrisc@vger.kernel.org,\n\tlinux-parisc@vger.kernel.org,\n\tlinux-sh@vger.kernel.org,\n\tlinux-arch@vger.kernel.org","Subject":"[RFC PATCH v1 6/9] uaccess: Change copy_{to/from}_user to return\n -EFAULT","Date":"Mon, 27 Apr 2026 19:13:47 +0200","Message-ID":"\n <1a55107abe15dd78450888e2b5327c3a56af29b7.1777306795.git.chleroy@kernel.org>","X-Mailer":"git-send-email 2.49.0","In-Reply-To":"","References":"","X-Mailing-List":"linuxppc-dev@lists.ozlabs.org","List-Id":"","List-Help":"","List-Owner":"","List-Post":"","List-Archive":",\n ","List-Subscribe":",\n ,\n ","List-Unsubscribe":"","Precedence":"list","MIME-Version":"1.0","X-Developer-Signature":"v=1; a=openpgp-sha256; l=2416; i=chleroy@kernel.org;\n h=from:subject:message-id; bh=x+yz+Ptlr8yUKihbRCrYsj2OzN4+HDHdWj3mTkeeywo=;\n b=owGbwMvMwCV2d0KB2p7V54MZT6slMWS+nxkjryH88LzkjscmK202zhcwuOPhcJTlidTVNdtCP\n 9vs/VPG2lHKwiDGxSArpshy/D/3rhldX1Lzp+7Sh5nDygQyhIGLUwAm0nCN4b9/yT75hpDtr4zk\n 9XPfORmtVO2p/XH+8bFg730PPNfMvn6dkWHDjsJSC09Vr9bDobdrxTgfMm1ckveKR+Rkud3skLM\n HLXgA","X-Developer-Key":"i=chleroy@kernel.org; a=openpgp;\n fpr=10FFE6F8B390DE17ACC2632368A92FEB01B8DD78","Content-Transfer-Encoding":"8bit","X-Spam-Status":"No, score=-0.2 required=5.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED,\n\tDKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF,SPF_HELO_NONE,SPF_PASS\n\tautolearn=disabled version=4.0.1","X-Spam-Checker-Version":"SpamAssassin 4.0.1 (2024-03-25) on lists.ozlabs.org"},"content":"Now that copy_{to/from}_user_partial() are used by callers which expect\npartial copy with number of not copied bytes as return value, change\ncopy_{to/from}_user() to return an int, and return -EFAULT when the\ncopy is not complete.\n\nSigned-off-by: Christophe Leroy (CS GROUP) \n---\n include/linux/uaccess.h | 28 ++++++++++++++++++++++++----\n 1 file changed, 24 insertions(+), 4 deletions(-)","diff":"diff --git a/include/linux/uaccess.h b/include/linux/uaccess.h\nindex 2d37173782b3..33b7d0f5f808 100644\n--- a/include/linux/uaccess.h\n+++ b/include/linux/uaccess.h\n@@ -211,7 +211,7 @@ extern __must_check unsigned long\n _copy_to_user(void __user *, const void *, unsigned long);\n \n static __always_inline unsigned long __must_check\n-copy_from_user(void *to, const void __user *from, unsigned long n)\n+copy_from_user_common(void *to, const void __user *from, unsigned long n, bool partial)\n {\n \tif (!check_copy_size(to, n, false))\n \t\treturn n;\n@@ -221,10 +221,20 @@ copy_from_user(void *to, const void __user *from, unsigned long n)\n \t\treturn _inline_copy_from_user(to, from, n);\n }\n \n-#define copy_from_user_partial copy_from_user\n+static __always_inline unsigned long __must_check\n+copy_from_user_partial(void *to, const void __user *from, unsigned long n)\n+{\n+\treturn copy_from_user_common(to, from, n, true);\n+}\n+\n+static __always_inline int __must_check\n+copy_from_user(void *to, const void __user *from, unsigned long n)\n+{\n+\treturn copy_from_user_common(to, from, n, false) ? -EFAULT : 0;\n+}\n \n static __always_inline unsigned long __must_check\n-copy_to_user(void __user *to, const void *from, unsigned long n)\n+copy_to_user_common(void __user *to, const void *from, unsigned long n, bool partial)\n {\n \tif (!check_copy_size(from, n, true))\n \t\treturn n;\n@@ -235,7 +245,17 @@ copy_to_user(void __user *to, const void *from, unsigned long n)\n \t\treturn _inline_copy_to_user(to, from, n);\n }\n \n-#define copy_to_user_partial copy_to_user\n+static __always_inline unsigned long __must_check\n+copy_to_user_partial(void __user *to, const void *from, unsigned long n)\n+{\n+\treturn copy_to_user_common(to, from, n, true);\n+}\n+\n+static __always_inline int __must_check\n+copy_to_user(void __user *to, const void *from, unsigned long n)\n+{\n+\treturn copy_to_user_common(to, from, n, false) ? -EFAULT : 0;\n+}\n \n #ifndef copy_mc_to_kernel\n /*\n","prefixes":["RFC","v1","6/9"]}