Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20;
From:   Ard Biesheuvel <ardb@kernel.org>
To:     linux-efi@vger.kernel.org
Cc:     linux-kernel@vger.kernel.org, Ard Biesheuvel <ardb@kernel.org>,
        Matthew Garrett <mjg59@srcf.ucam.org>,
        Peter Jones <pjones@redhat.com>,
        Tony Luck <tony.luck@intel.com>,
        Kees Cook <keescook@chromium.org>,
        Thomas Gleixner <tglx@linutronix.de>,
        Ingo Molnar <mingo@redhat.com>, Borislav Petkov <bp@alien8.de>,
        Dave Hansen <dave.hansen@linux.intel.com>
Subject: [PATCH v2 1/9] pstore: Don't expose ECC metadata via pstore file system
Date:   Tue, 21 Jun 2022 17:36:15 +0200
Message-Id: <20220621153623.3786960-2-ardb@kernel.org>
In-Reply-To: <20220621153623.3786960-1-ardb@kernel.org>
References: <20220621153623.3786960-1-ardb@kernel.org>
MIME-Version: 1.0
Content-Transfer-Encoding: 8bit
Precedence: bulk

If a pstore record has its ecc_notice_size field set to >0, it means the
record's buffer has that many additional bytes appended to the end that
carry backend specific metadata, typically used for error correction.

Given that this is backend specific, and that user space cannot really
make sense of this metadata anyway, let's not expose it via the pstore
filesystem.

Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
---
 fs/pstore/inode.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/fs/pstore/inode.c b/fs/pstore/inode.c
index 14658b009f1b..b62eead3f801 100644
--- a/fs/pstore/inode.c
+++ b/fs/pstore/inode.c
@@ -349,7 +349,7 @@ int pstore_mkfile(struct dentry *root, struct pstore_record *record)
 	int			rc = 0;
 	char			name[PSTORE_NAMELEN];
 	struct pstore_private	*private, *pos;
-	size_t			size = record->size + record->ecc_notice_size;
+	size_t			size = record->size;
 
 	if (WARN_ON(!inode_is_locked(d_inode(root))))
 		return -EINVAL;
-- 
2.35.1