[PATCH v8 27/28] LSM: Add /proc attr entry for full LSM context
From: Casey Schaufler <casey@schaufler-ca.com>
Date: 2019-08-29 23:30:27
Also in:
selinux
Subsystem:
filesystems (vfs and infrastructure), proc filesystem, security subsystem, the rest · Maintainers:
Alexander Viro, Christian Brauner, Paul Moore, James Morris, "Serge E. Hallyn", Linus Torvalds
Add an entry /proc/.../attr/context which displays the full
process security "context" in compound format:'
lsm1\0value\0lsm2\0value\0...
This entry is not writable.
Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
---
fs/proc/base.c | 1 +
security/security.c | 27 +++++++++++++++++++++++++++
2 files changed, 28 insertions(+)
diff --git a/fs/proc/base.c b/fs/proc/base.c
index 7bf70e041315..79600df5f7a2 100644
--- a/fs/proc/base.c
+++ b/fs/proc/base.c@@ -2619,6 +2619,7 @@ static const struct pid_entry attr_dir_stuff[] = { ATTR(NULL, "keycreate", 0666), ATTR(NULL, "sockcreate", 0666), ATTR(NULL, "display", 0666), + ATTR(NULL, "context", 0666), #ifdef CONFIG_SECURITY_SMACK DIR("smack", 0555, proc_smack_attr_dir_inode_ops, proc_smack_attr_dir_ops),
diff --git a/security/security.c b/security/security.c
index 8cb91f33c166..d151ac4a398b 100644
--- a/security/security.c
+++ b/security/security.c@@ -2082,6 +2082,10 @@ int security_getprocattr(struct task_struct *p, const char *lsm, char *name, char **value) { struct security_hook_list *hp; + char *final = NULL; + char *cp; + int rc = 0; + int finallen = 0; int display = lsm_task_display(current); int slot = 0;
@@ -2099,6 +2103,29 @@ int security_getprocattr(struct task_struct *p, const char *lsm, char *name, return -ENOMEM; } + if (!strcmp(name, "context")) { + hlist_for_each_entry(hp, &security_hook_heads.getprocattr, + list) { + rc = hp->hook.getprocattr(p, "current", &cp); + if (rc == -EINVAL || rc == -ENOPROTOOPT) + continue; + if (rc < 0) { + kfree(final); + return rc; + } + rc = append_ctx(&final, &finallen, hp->lsmid->lsm, + cp, rc); + if (rc < 0) { + kfree(final); + return rc; + } + } + if (final == NULL) + return -EINVAL; + *value = final; + return finallen; + } + hlist_for_each_entry(hp, &security_hook_heads.getprocattr, list) { if (lsm != NULL && strcmp(lsm, hp->lsmid->lsm)) continue;
--
2.20.1