Re: [PATCH v5 08/23] evm: Align evm_inode_post_setxattr() definition with LSM infrastructure

From: Casey Schaufler
Date: Tue Nov 07 2023 - 12:28:23 EST


On 11/7/2023 5:39 AM, Roberto Sassu wrote:
> From: Roberto Sassu <roberto.sassu@xxxxxxxxxx>
>
> Change evm_inode_post_setxattr() definition, so that it can be registered
> as implementation of the inode_post_setxattr hook.
>
> Signed-off-by: Roberto Sassu <roberto.sassu@xxxxxxxxxx>
> Reviewed-by: Stefan Berger <stefanb@xxxxxxxxxxxxx>
> Reviewed-by: Mimi Zohar <zohar@xxxxxxxxxxxxx>

Reviewed-by: Casey Schaufler <casey@xxxxxxxxxxxxxxxx>


> ---
> include/linux/evm.h | 8 +++++---
> security/integrity/evm/evm_main.c | 4 +++-
> security/security.c | 2 +-
> 3 files changed, 9 insertions(+), 5 deletions(-)
>
> diff --git a/include/linux/evm.h b/include/linux/evm.h
> index 7c6a74dbc093..437d4076a3b3 100644
> --- a/include/linux/evm.h
> +++ b/include/linux/evm.h
> @@ -31,7 +31,8 @@ extern int evm_inode_setxattr(struct mnt_idmap *idmap,
> extern void evm_inode_post_setxattr(struct dentry *dentry,
> const char *xattr_name,
> const void *xattr_value,
> - size_t xattr_value_len);
> + size_t xattr_value_len,
> + int flags);
> extern int evm_inode_removexattr(struct mnt_idmap *idmap,
> struct dentry *dentry, const char *xattr_name);
> extern void evm_inode_post_removexattr(struct dentry *dentry,
> @@ -55,7 +56,7 @@ static inline void evm_inode_post_set_acl(struct dentry *dentry,
> const char *acl_name,
> struct posix_acl *kacl)
> {
> - return evm_inode_post_setxattr(dentry, acl_name, NULL, 0);
> + return evm_inode_post_setxattr(dentry, acl_name, NULL, 0, 0);
> }
>
> int evm_inode_init_security(struct inode *inode, struct inode *dir,
> @@ -114,7 +115,8 @@ static inline int evm_inode_setxattr(struct mnt_idmap *idmap,
> static inline void evm_inode_post_setxattr(struct dentry *dentry,
> const char *xattr_name,
> const void *xattr_value,
> - size_t xattr_value_len)
> + size_t xattr_value_len,
> + int flags)
> {
> return;
> }
> diff --git a/security/integrity/evm/evm_main.c b/security/integrity/evm/evm_main.c
> index 7fc083d53fdf..ea84a6f835ff 100644
> --- a/security/integrity/evm/evm_main.c
> +++ b/security/integrity/evm/evm_main.c
> @@ -730,6 +730,7 @@ bool evm_revalidate_status(const char *xattr_name)
> * @xattr_name: pointer to the affected extended attribute name
> * @xattr_value: pointer to the new extended attribute value
> * @xattr_value_len: pointer to the new extended attribute value length
> + * @flags: flags to pass into filesystem operations
> *
> * Update the HMAC stored in 'security.evm' to reflect the change.
> *
> @@ -738,7 +739,8 @@ bool evm_revalidate_status(const char *xattr_name)
> * i_mutex lock.
> */
> void evm_inode_post_setxattr(struct dentry *dentry, const char *xattr_name,
> - const void *xattr_value, size_t xattr_value_len)
> + const void *xattr_value, size_t xattr_value_len,
> + int flags)
> {
> if (!evm_revalidate_status(xattr_name))
> return;
> diff --git a/security/security.c b/security/security.c
> index ae3625198c9f..53793f3cb36a 100644
> --- a/security/security.c
> +++ b/security/security.c
> @@ -2367,7 +2367,7 @@ void security_inode_post_setxattr(struct dentry *dentry, const char *name,
> if (unlikely(IS_PRIVATE(d_backing_inode(dentry))))
> return;
> call_void_hook(inode_post_setxattr, dentry, name, value, size, flags);
> - evm_inode_post_setxattr(dentry, name, value, size);
> + evm_inode_post_setxattr(dentry, name, value, size, flags);
> }
>
> /**