[PATCH v8 08/19] ima: Use mac_admin_ns_capable() to check corresponding capability
From: Stefan Berger <hidden>
Date: 2022-01-04 17:05:29
Also in:
linux-integrity, lkml
Subsystem:
capabilities, extended verification module (evm), integrity measurement architecture (ima), security subsystem, the rest · Maintainers:
Serge Hallyn, Mimi Zohar, Roberto Sassu, Dmitry Kasatkin, Paul Moore, James Morris, "Serge E. Hallyn", Linus Torvalds
From: Stefan Berger <stefanb@linux.ibm.com> Use mac_admin_ns_capable() to check corresponding capability to allow read/write IMA policy without CAP_SYS_ADMIN but with CAP_MAC_ADMIN. Signed-off-by: Denis Semakin <redacted> Signed-off-by: Stefan Berger <stefanb@linux.ibm.com> --- include/linux/capability.h | 6 ++++++ security/integrity/ima/ima.h | 6 ++++++ security/integrity/ima/ima_fs.c | 3 ++- 3 files changed, 14 insertions(+), 1 deletion(-)
diff --git a/include/linux/capability.h b/include/linux/capability.h
index 65efb74c3585..991579178f32 100644
--- a/include/linux/capability.h
+++ b/include/linux/capability.h@@ -270,6 +270,12 @@ static inline bool checkpoint_restore_ns_capable(struct user_namespace *ns) ns_capable(ns, CAP_SYS_ADMIN); } +static inline bool mac_admin_ns_capable(struct user_namespace *ns) +{ + return ns_capable(ns, CAP_MAC_ADMIN) || + ns_capable(ns, CAP_SYS_ADMIN); +} + /* audit system wants to get cap info from files as well */ int get_vfs_caps_from_disk(struct user_namespace *mnt_userns, const struct dentry *dentry,
diff --git a/security/integrity/ima/ima.h b/security/integrity/ima/ima.h
index 224b09617c52..0c86a955cedf 100644
--- a/security/integrity/ima/ima.h
+++ b/security/integrity/ima/ima.h@@ -483,6 +483,12 @@ static inline int ima_filter_rule_match(u32 secid, u32 field, u32 op, #define POLICY_FILE_FLAGS S_IWUSR #endif /* CONFIG_IMA_READ_POLICY */ +static inline +struct user_namespace *ima_user_ns_from_file(const struct file *filp) +{ + return file_inode(filp)->i_sb->s_user_ns; +} + static inline struct ima_namespace *get_current_ns(void) { return &init_ima_ns;
diff --git a/security/integrity/ima/ima_fs.c b/security/integrity/ima/ima_fs.c
index 5b6404991b37..71302bb5427f 100644
--- a/security/integrity/ima/ima_fs.c
+++ b/security/integrity/ima/ima_fs.c@@ -377,6 +377,7 @@ static const struct seq_operations ima_policy_seqops = { */ static int ima_open_policy(struct inode *inode, struct file *filp) { + struct user_namespace *user_ns = ima_user_ns_from_file(filp); struct ima_namespace *ns = &init_ima_ns; if (!(filp->f_flags & O_WRONLY)) {
@@ -385,7 +386,7 @@ static int ima_open_policy(struct inode *inode, struct file *filp) #else if ((filp->f_flags & O_ACCMODE) != O_RDONLY) return -EACCES; - if (!capable(CAP_SYS_ADMIN)) + if (!mac_admin_ns_capable(user_ns)) return -EPERM; return seq_open(filp, &ima_policy_seqops); #endif
--
2.31.1