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AJvYcCVcak8zmNCOKxjIYsoZP2t9J9UgSikgV5vXGVkn7BTpOjMZyvOk/y4alg00vU0SMe/xKaDJgaIwfAPENRA=@vger.kernel.org X-Gm-Message-State: AOJu0YwxIBrXLJDOnx6R3doV4XgOf9dRo8jQFsWL0UgH6s3wwu9o+My7 kvtZBUpLqPFUe8R/uZt0svEc44QwiGbJNO8CDVYKzVEvNfuGskMvQTjuwSC5jX3/bvOalh/qFxL z3/SuNg== X-Google-Smtp-Source: AGHT+IHi0gSVKxF9796sY6n1cVcgNiz/fsNc836mupUZtqmyvJTlnsLOXeqwbXzuTlIf+2iUj78FZGeorFh0 X-Received: from anyblade.c.googlers.com ([fda3:e722:ac3:cc00:20:ed76:c0a8:1791]) (user=mmaurer job=sendgmr) by 2002:a05:690c:2a92:b0:6e2:2600:ed65 with SMTP id 00721157ae682-6e22600f35dmr247467b3.1.1727307584197; Wed, 25 Sep 2024 16:39:44 -0700 (PDT) Date: Wed, 25 Sep 2024 23:38:25 +0000 In-Reply-To: <20240925233854.90072-1-mmaurer@google.com> Precedence: bulk X-Mailing-List: linux-kbuild@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 References: <20240925233854.90072-1-mmaurer@google.com> X-Mailer: git-send-email 2.46.1.824.gd892dcdcdd-goog Message-ID: <20240925233854.90072-11-mmaurer@google.com> Subject: [PATCH v5 10/16] module: Factor out elf_validity_cache_strtab From: Matthew Maurer To: masahiroy@kernel.org, ndesaulniers@google.com, ojeda@kernel.org, gary@garyguo.net, mcgrof@kernel.org, Alex Gaynor Cc: rust-for-linux@vger.kernel.org, linux-kbuild@vger.kernel.org, linux-kernel@vger.kernel.org, neal@gompa.dev, marcan@marcan.st, j@jannau.net, asahi@lists.linux.dev, linux-modules@vger.kernel.org, Matthew Maurer , Petr Pavlu , Sami Tolvanen , Daniel Gomez , Boqun Feng , " =?utf-8?q?Bj=C3=B6rn_Roy_Baron?= " , Benno Lossin , Andreas Hindborg , Alice Ryhl , Trevor Gross This patch only moves the existing strtab population to a function. Validation comes in a following patch, this is split out to make the new validation checks more clearly separated. Signed-off-by: Matthew Maurer --- kernel/module/main.c | 23 ++++++++++++++++++++--- 1 file changed, 20 insertions(+), 3 deletions(-) diff --git a/kernel/module/main.c b/kernel/module/main.c index e04a228c694a..c082d5d41a8d 100644 --- a/kernel/module/main.c +++ b/kernel/module/main.c @@ -2089,6 +2089,23 @@ static int elf_validity_cache_index(struct load_info *info, int flags) return 0; } +/** + * elf_validity_cache_strtab() - Cache symbol string table + * @info: Load info to read from and update. + * Must have &load_info->sechdrs and &load_info->secstrings populated. + * Must have &load_info->index populated. + * + * Return: 0 on success, negative error code if a check failed. + */ +static int elf_validity_cache_strtab(struct load_info *info) +{ + Elf_Shdr *str_shdr = &info->sechdrs[info->index.str]; + char *strtab = (char *)info->hdr + str_shdr->sh_offset; + + info->strtab = strtab; + return 0; +} + /* * Check userspace passed ELF module against our expectations, and cache * useful variables for further processing as we go. @@ -2122,9 +2139,9 @@ static int elf_validity_cache_copy(struct load_info *info, int flags) err = elf_validity_cache_index(info, flags); if (err < 0) return err; - - /* Sets internal strings. */ - info->strtab = (char *)info->hdr + info->sechdrs[info->index.str].sh_offset; + err = elf_validity_cache_strtab(info); + if (err < 0) + return err; /* This is temporary: point mod into copy of data. */ info->mod = (void *)info->hdr + info->sechdrs[info->index.mod].sh_offset;