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[34.83.59.201]) by smtp.gmail.com with UTF8SMTPSA id 98e67ed59e1d1-2fceb093d96sm6756326a91.40.2025.02.24.09.45.22 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Mon, 24 Feb 2025 09:45:22 -0800 (PST) From: jeffxu@chromium.org To: akpm@linux-foundation.org, keescook@chromium.org, jannh@google.com, torvalds@linux-foundation.org, vbabka@suse.cz, lorenzo.stoakes@oracle.com, Liam.Howlett@Oracle.com, adhemerval.zanella@linaro.org, oleg@redhat.com, avagin@gmail.com, benjamin@sipsolutions.net Cc: linux-kernel@vger.kernel.org, linux-hardening@vger.kernel.org, linux-mm@kvack.org, jorgelo@chromium.org, sroettger@google.com, hch@lst.de, ojeda@kernel.org, thomas.weissschuh@linutronix.de, adobriyan@gmail.com, johannes@sipsolutions.net, pedro.falcato@gmail.com, hca@linux.ibm.com, willy@infradead.org, anna-maria@linutronix.de, mark.rutland@arm.com, linus.walleij@linaro.org, Jason@zx2c4.com, deller@gmx.de, rdunlap@infradead.org, davem@davemloft.net, peterx@redhat.com, f.fainelli@gmail.com, gerg@kernel.org, dave.hansen@linux.intel.com, mingo@kernel.org, ardb@kernel.org, mhocko@suse.com, 42.hyeyoo@gmail.com, peterz@infradead.org, ardb@google.com, enh@google.com, rientjes@google.com, groeck@chromium.org, mpe@ellerman.id.au, aleksandr.mikhalitsyn@canonical.com, mike.rapoport@gmail.com, Jeff Xu Subject: [PATCH v6 7/7] mseal, system mappings: update mseal.rst Date: Mon, 24 Feb 2025 17:45:13 +0000 Message-ID: <20250224174513.3600914-8-jeffxu@google.com> X-Mailer: git-send-email 2.48.1.658.g4767266eb4-goog In-Reply-To: <20250224174513.3600914-1-jeffxu@google.com> References: <20250224174513.3600914-1-jeffxu@google.com> Precedence: bulk X-Mailing-List: linux-hardening@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 From: Jeff Xu Update memory sealing documentation to include details about system mappings. Signed-off-by: Jeff Xu Reviewed-by: Kees Cook --- Documentation/userspace-api/mseal.rst | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/Documentation/userspace-api/mseal.rst b/Documentation/userspace-api/mseal.rst index 41102f74c5e2..10147281bf2d 100644 --- a/Documentation/userspace-api/mseal.rst +++ b/Documentation/userspace-api/mseal.rst @@ -130,6 +130,13 @@ Use cases - Chrome browser: protect some security sensitive data structures. +- System mappings: + If supported by an architecture (via CONFIG_ARCH_HAS_MSEAL_SYSTEM_MAPPINGS), + the CONFIG_MSEAL_SYSTEM_MAPPINGS seals system mappings, e.g. vdso, vvar, + uprobes, sigpage, vectors, etc. CHECKPOINT_RESTORE, UML, gVisor, rr are + known to relocate or unmap system mapping, therefore this config can't be + enabled universally. + When not to use mseal ===================== Applications can apply sealing to any virtual memory region from userspace,