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[82.69.66.36]) by smtp.gmail.com with ESMTPSA id ffacd0b85a97d-4325c052d34sm3601755f8f.25.2025.12.20.13.56.22 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sat, 20 Dec 2025 13:56:22 -0800 (PST) From: david.laight.linux@gmail.com To: Thomas Gleixner , Linus Torvalds , Peter Zijlstra , Mathieu Desnoyers , Kees Cook , linux-kernel@vger.kernel.org, akpm@linux-foundation.org, Al Viro Cc: David Laight Subject: [PATCH 4/5] uaccess: Disable -Wshadow in __scoped_user_access() Date: Sat, 20 Dec 2025 21:56:07 +0000 Message-Id: <20251220215608.434614-5-david.laight.linux@gmail.com> X-Mailer: git-send-email 2.39.5 In-Reply-To: <20251220215608.434614-1-david.laight.linux@gmail.com> References: <20251220215608.434614-1-david.laight.linux@gmail.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" From: David Laight -Wshadow is enabled by W=3D2 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 589cb2ef2e7b..e2ff4146c5d0 100644 --- a/include/linux/uaccess.h +++ b/include/linux/uaccess.h @@ -754,7 +754,9 @@ USER_ACCESS_GUARD(rw, void) with (typeof(uptr) _tmpptr =3D __scoped_user_access_begin(mode, uptr, siz= e, elbl)) \ and_with (CLASS(user_##mode##_access, scope)(_tmpptr)) \ /* Force modified pointer usage within the scope */ \ - and_with (const typeof(uptr) uptr =3D _tmpptr) + __diag_push() __diag_ignore_all("-Wshadow", "uptr is readonly copy") \ + and_with (const typeof(uptr) uptr =3D _tmpptr) \ + __diag_pop() =20 /** * scoped_user_read_access_size - Start a scoped user read access with giv= en size --=20 2.39.5