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Received: from [10.9.9.73] (helo=submission02.runbox) by mailtransmit03.runbox with esmtp (Exim 4.86_2) (envelope-from ) id 1vx3Jw-0001hU-9m; Mon, 02 Mar 2026 14:28:24 +0100 Received: by submission02.runbox with esmtpsa [Authenticated ID (1493616)] (TLS1.2:ECDHE_SECP256R1__RSA_PSS_RSAE_SHA256__AES_256_GCM:256) (Exim 4.93) id 1vx3Jj-008UTR-SY; Mon, 02 Mar 2026 14:28:11 +0100 From: david.laight.linux@gmail.com To: Alexander Viro , Andre Almeida , Andrew Cooper , Christian Borntraeger , Christian Brauner , Christophe Leroy , "Christophe Leroy (CS GROUP)" , Darren Hart , David Laight , Davidlohr Bueso , Heiko Carstens , Jan Kara , Julia Lawall , Linus Torvalds , linux-arm-kernel@lists.infradead.org, linux-fsdevel@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, linux-riscv@lists.infradead.org, linux-s390@vger.kernel.org, LKML , Madhavan Srinivasan , Mathieu Desnoyers , Michael Ellerman , Nicholas Piggin , Nicolas Palix , Palmer Dabbelt , Paul Walmsley , Peter Zijlstra , Russell King , Sven Schnelle , Thomas Gleixner , x86@kernel.org, Kees Cook , akpm@linux-foundation.org Subject: [PATCH v2 4/5] uaccess: Disable -Wshadow in __scoped_user_access() Date: Mon, 2 Mar 2026 13:27:54 +0000 Message-Id: <20260302132755.1475451-5-david.laight.linux@gmail.com> X-Mailer: git-send-email 2.39.5 In-Reply-To: <20260302132755.1475451-1-david.laight.linux@gmail.com> References: <20260302132755.1475451-1-david.laight.linux@gmail.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20260302_132832_109501_7236CBA0 X-CRM114-Status: GOOD ( 11.95 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org From: David Laight -Wshadow is enabled by W=2 builds and __scoped_user_access() quite deliberately creates a 'const' shadow of the 'user' address that references a 'guard page' when the application passes a kernel pointer. Signed-off-by: David Laight --- include/linux/uaccess.h | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/include/linux/uaccess.h b/include/linux/uaccess.h index 64bc2492eb99..445391ec5a6d 100644 --- a/include/linux/uaccess.h +++ b/include/linux/uaccess.h @@ -739,7 +739,9 @@ static __always_inline void __scoped_user_rw_access_end(const void *p) #define __scoped_user_access(mode, uptr, size, elbl) \ with (auto _tmpptr = __scoped_user_access_begin(mode, uptr, size, elbl)) \ /* Force modified pointer usage within the scope */ \ - and_with (const auto uptr __cleanup(__scoped_user_##mode##_access_end) = _tmpptr) + __diag_push() __diag_ignore_all("-Wshadow", "uptr is readonly copy") \ + and_with (const auto uptr __cleanup(__scoped_user_##mode##_access_end) = _tmpptr) \ + __diag_pop() /** * scoped_user_read_access_size - Start a scoped user read access with given size -- 2.39.5