Re: [PATCH v7 1/6] reiserfs: Switch to security_inode_init_security()
From: Mimi Zohar <zohar@linux.ibm.com>
Date: 2023-02-17 19:48:21
Also in:
linux-integrity, lkml, ocfs2-devel, selinux
On Thu, 2022-12-01 at 11:41 +0100, Roberto Sassu wrote:
From: Roberto Sassu <roberto.sassu@huawei.com> In preparation for removing security_old_inode_init_security(), switch to security_inode_init_security(). Define the initxattrs callback reiserfs_initxattrs(), to populate the name/value/len triple in the reiserfs_security_handle() with the first xattr provided by LSMs. Make a copy of the xattr value, as security_inode_init_security() frees it. After the call to security_inode_init_security(), remove the check for returning -EOPNOTSUPP, as security_inode_init_security() changes it to zero. Multiple xattrs are currently not supported, as the reiserfs_security_handle structure is exported to user space. As a consequence, even if EVM is invoked, it will not provide an xattr (if it is not the first to set it, its xattr will be discarded; if it is the first, it does not have xattrs to calculate the HMAC on). Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com> Reviewed-by: Casey Schaufler <casey@schaufler-ca.com>
Now that commit 572302af1258 ("reiserfs: Add missing calls to
reiserfs_security_free()") is upstreamed, please include a dependency
comment.
Reviewed-by: Mimi Zohar <zohar@linux.ibm.com>
quoted hunk ↗ jump to hunk
--- fs/reiserfs/xattr_security.c | 23 ++++++++++++++++++----- 1 file changed, 18 insertions(+), 5 deletions(-)diff --git a/fs/reiserfs/xattr_security.c b/fs/reiserfs/xattr_security.c index 857a65b05726..0ba96757681d 100644 --- a/fs/reiserfs/xattr_security.c +++ b/fs/reiserfs/xattr_security.c@@ -39,6 +39,22 @@ static bool security_list(struct dentry *dentry) return !IS_PRIVATE(d_inode(dentry)); } +static int +reiserfs_initxattrs(struct inode *inode, const struct xattr *xattr_array, + void *fs_info) +{ + struct reiserfs_security_handle *sec = fs_info; + + sec->value = kmemdup(xattr_array->value, xattr_array->value_len, + GFP_KERNEL); + if (!sec->value) + return -ENOMEM; + + sec->name = xattr_array->name; + sec->length = xattr_array->value_len; + return 0; +} + /* Initializes the security context for a new inode and returns the number * of blocks needed for the transaction. If successful, reiserfs_security * must be released using reiserfs_security_free when the caller is done. */@@ -56,12 +72,9 @@ int reiserfs_security_init(struct inode *dir, struct inode *inode, if (IS_PRIVATE(dir)) return 0; - error = security_old_inode_init_security(inode, dir, qstr, &sec->name, - &sec->value, &sec->length); + error = security_inode_init_security(inode, dir, qstr, + &reiserfs_initxattrs, sec); if (error) { - if (error == -EOPNOTSUPP) - error = 0; - sec->name = NULL; sec->value = NULL; sec->length = 0;