{"id":2229048,"url":"http://patchwork.ozlabs.org/api/1.1/patches/2229048/?format=json","web_url":"http://patchwork.ozlabs.org/project/linux-arc/patch/1a55107abe15dd78450888e2b5327c3a56af29b7.1777306795.git.chleroy@kernel.org/","project":{"id":48,"url":"http://patchwork.ozlabs.org/api/1.1/projects/48/?format=json","name":"Linux ARC development","link_name":"linux-arc","list_id":"linux-snps-arc.lists.infradead.org","list_email":"linux-snps-arc@lists.infradead.org","web_url":"","scm_url":"","webscm_url":""},"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/linux-arc/patch/1a55107abe15dd78450888e2b5327c3a56af29b7.1777306795.git.chleroy@kernel.org/mbox/","series":[{"id":501692,"url":"http://patchwork.ozlabs.org/api/1.1/series/501692/?format=json","web_url":"http://patchwork.ozlabs.org/project/linux-arc/list/?series=501692","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/501692/mbox/"}],"comments":"http://patchwork.ozlabs.org/api/patches/2229048/comments/","check":"pending","checks":"http://patchwork.ozlabs.org/api/patches/2229048/checks/","tags":{},"headers":{"Return-Path":"\n ","X-Original-To":"incoming@patchwork.ozlabs.org","Delivered-To":"patchwork-incoming@legolas.ozlabs.org","Authentication-Results":["legolas.ozlabs.org;\n\tdkim=pass (2048-bit key;\n secure) header.d=lists.infradead.org header.i=@lists.infradead.org\n header.a=rsa-sha256 header.s=bombadil.20210309 header.b=X4kSC1Pt;\n\tdkim=fail reason=\"signature verification failed\" (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=none (no SPF record) smtp.mailfrom=lists.infradead.org\n (client-ip=2607:7c80:54:3::133; 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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","X-CRM114-Version":"20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 ","X-CRM114-CacheID":"sfid-20260427_101846_369728_53A92076 ","X-CRM114-Status":"UNSURE ( 9.10 )","X-CRM114-Notice":"Please train this message.","X-Spam-Score":"-2.1 (--)","X-Spam-Report":"Spam detection software,\n running on the system \"bombadil.infradead.org\",\n has NOT identified this incoming email as spam. The original\n message has been attached to this so you can view it or label\n similar future email. If you have any questions, see\n the administrator of that system for details.\n Content preview: Now that copy_{to/from}_user_partial() are used by callers\n which expect partial copy with number of not copied bytes as return value,\n change copy_{to/from}_user() to return an int, and return -EFAULT [...]\n Content analysis details: (-2.1 points, 5.0 required)\n pts rule name description\n ---- ----------------------\n --------------------------------------------------\n -0.0 SPF_PASS SPF: sender matches SPF record\n 0.0 SPF_HELO_NONE SPF: HELO does not publish an SPF Record\n -0.1 DKIM_VALID_EF Message has a valid DKIM or DK signature from\n envelope-from domain\n -0.1 DKIM_VALID_AU Message has a valid DKIM or DK signature from\n author's\n domain\n -0.1 DKIM_VALID Message has at least one valid DKIM or DK\n signature\n 0.1 DKIM_SIGNED Message has a DKIM or DK signature,\n not necessarily valid\n -1.9 BAYES_00 BODY: Bayes spam probability is 0 to 1%\n [score: 0.0000]\n -0.0 DKIMWL_WL_HIGH DKIMwl.org - High trust sender","X-BeenThere":"linux-snps-arc@lists.infradead.org","X-Mailman-Version":"2.1.34","Precedence":"list","List-Id":"Linux on Synopsys ARC Processors ","List-Unsubscribe":",\n ","List-Archive":"","List-Post":"","List-Help":"","List-Subscribe":",\n ","Content-Type":"text/plain; charset=\"us-ascii\"","Content-Transfer-Encoding":"7bit","Sender":"\"linux-snps-arc\" ","Errors-To":"\n linux-snps-arc-bounces+incoming=patchwork.ozlabs.org@lists.infradead.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"]}