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-rw-r--r--fs/notify/dnotify/dnotify.c15
-rw-r--r--fs/notify/fanotify/fanotify_user.c19
-rw-r--r--fs/notify/inotify/inotify_user.c14
-rw-r--r--include/linux/lsm_hooks.h9
-rw-r--r--include/linux/security.h10
-rw-r--r--security/security.c6
-rw-r--r--security/selinux/hooks.c47
-rw-r--r--security/selinux/include/classmap.h5
8 files changed, 113 insertions, 12 deletions
diff --git a/fs/notify/dnotify/dnotify.c b/fs/notify/dnotify/dnotify.c
index 250369d6901d..87a7f61bc91c 100644
--- a/fs/notify/dnotify/dnotify.c
+++ b/fs/notify/dnotify/dnotify.c
@@ -22,6 +22,7 @@
#include <linux/sched/signal.h>
#include <linux/dnotify.h>
#include <linux/init.h>
+#include <linux/security.h>
#include <linux/spinlock.h>
#include <linux/slab.h>
#include <linux/fdtable.h>
@@ -288,6 +289,17 @@ int fcntl_dirnotify(int fd, struct file *filp, unsigned long arg)
goto out_err;
}
+ /*
+ * convert the userspace DN_* "arg" to the internal FS_*
+ * defined in fsnotify
+ */
+ mask = convert_arg(arg);
+
+ error = security_path_notify(&filp->f_path, mask,
+ FSNOTIFY_OBJ_TYPE_INODE);
+ if (error)
+ goto out_err;
+
/* expect most fcntl to add new rather than augment old */
dn = kmem_cache_alloc(dnotify_struct_cache, GFP_KERNEL);
if (!dn) {
@@ -302,9 +314,6 @@ int fcntl_dirnotify(int fd, struct file *filp, unsigned long arg)
goto out_err;
}
- /* convert the userspace DN_* "arg" to the internal FS_* defines in fsnotify */
- mask = convert_arg(arg);
-
/* set up the new_fsn_mark and new_dn_mark */
new_fsn_mark = &new_dn_mark->fsn_mark;
fsnotify_init_mark(new_fsn_mark, dnotify_group);
diff --git a/fs/notify/fanotify/fanotify_user.c b/fs/notify/fanotify/fanotify_user.c
index a90bb19dcfa2..8b4e2ad6d208 100644
--- a/fs/notify/fanotify/fanotify_user.c
+++ b/fs/notify/fanotify/fanotify_user.c
@@ -528,7 +528,8 @@ static const struct file_operations fanotify_fops = {
};
static int fanotify_find_path(int dfd, const char __user *filename,
- struct path *path, unsigned int flags)
+ struct path *path, unsigned int flags, __u64 mask,
+ unsigned int obj_type)
{
int ret;
@@ -567,8 +568,15 @@ static int fanotify_find_path(int dfd, const char __user *filename,
/* you can only watch an inode if you have read permissions on it */
ret = inode_permission(path->dentry->d_inode, MAY_READ);
+ if (ret) {
+ path_put(path);
+ goto out;
+ }
+
+ ret = security_path_notify(path, mask, obj_type);
if (ret)
path_put(path);
+
out:
return ret;
}
@@ -931,6 +939,7 @@ static int do_fanotify_mark(int fanotify_fd, unsigned int flags, __u64 mask,
__kernel_fsid_t __fsid, *fsid = NULL;
u32 valid_mask = FANOTIFY_EVENTS | FANOTIFY_EVENT_FLAGS;
unsigned int mark_type = flags & FANOTIFY_MARK_TYPE_BITS;
+ unsigned int obj_type;
int ret;
pr_debug("%s: fanotify_fd=%d flags=%x dfd=%d pathname=%p mask=%llx\n",
@@ -945,8 +954,13 @@ static int do_fanotify_mark(int fanotify_fd, unsigned int flags, __u64 mask,
switch (mark_type) {
case FAN_MARK_INODE:
+ obj_type = FSNOTIFY_OBJ_TYPE_INODE;
+ break;
case FAN_MARK_MOUNT:
+ obj_type = FSNOTIFY_OBJ_TYPE_VFSMOUNT;
+ break;
case FAN_MARK_FILESYSTEM:
+ obj_type = FSNOTIFY_OBJ_TYPE_SB;
break;
default:
return -EINVAL;
@@ -1014,7 +1028,8 @@ static int do_fanotify_mark(int fanotify_fd, unsigned int flags, __u64 mask,
goto fput_and_out;
}
- ret = fanotify_find_path(dfd, pathname, &path, flags);
+ ret = fanotify_find_path(dfd, pathname, &path, flags,
+ (mask & ALL_FSNOTIFY_EVENTS), obj_type);
if (ret)
goto fput_and_out;
diff --git a/fs/notify/inotify/inotify_user.c b/fs/notify/inotify/inotify_user.c
index 7b53598c8804..408e9917ed42 100644
--- a/fs/notify/inotify/inotify_user.c
+++ b/fs/notify/inotify/inotify_user.c
@@ -39,6 +39,7 @@
#include <linux/poll.h>
#include <linux/wait.h>
#include <linux/memcontrol.h>
+#include <linux/security.h>
#include "inotify.h"
#include "../fdinfo.h"
@@ -342,7 +343,8 @@ static const struct file_operations inotify_fops = {
/*
* find_inode - resolve a user-given path to a specific inode
*/
-static int inotify_find_inode(const char __user *dirname, struct path *path, unsigned flags)
+static int inotify_find_inode(const char __user *dirname, struct path *path,
+ unsigned int flags, __u64 mask)
{
int error;
@@ -351,8 +353,15 @@ static int inotify_find_inode(const char __user *dirname, struct path *path, uns
return error;
/* you can only watch an inode if you have read permissions on it */
error = inode_permission(path->dentry->d_inode, MAY_READ);
+ if (error) {
+ path_put(path);
+ return error;
+ }
+ error = security_path_notify(path, mask,
+ FSNOTIFY_OBJ_TYPE_INODE);
if (error)
path_put(path);
+
return error;
}
@@ -744,7 +753,8 @@ SYSCALL_DEFINE3(inotify_add_watch, int, fd, const char __user *, pathname,
if (mask & IN_ONLYDIR)
flags |= LOOKUP_DIRECTORY;
- ret = inotify_find_inode(pathname, &path, flags);
+ ret = inotify_find_inode(pathname, &path, flags,
+ (mask & IN_ALL_EVENTS));
if (ret)
goto fput_and_out;
diff --git a/include/linux/lsm_hooks.h b/include/linux/lsm_hooks.h
index 47f58cfb6a19..ead98af9c602 100644
--- a/include/linux/lsm_hooks.h
+++ b/include/linux/lsm_hooks.h
@@ -339,6 +339,9 @@
* Check for permission to change root directory.
* @path contains the path structure.
* Return 0 if permission is granted.
+ * @path_notify:
+ * Check permissions before setting a watch on events as defined by @mask,
+ * on an object at @path, whose type is defined by @obj_type.
* @inode_readlink:
* Check the permission to read the symbolic link.
* @dentry contains the dentry structure for the file link.
@@ -1535,7 +1538,9 @@ union security_list_options {
int (*path_chown)(const struct path *path, kuid_t uid, kgid_t gid);
int (*path_chroot)(const struct path *path);
#endif
-
+ /* Needed for inode based security check */
+ int (*path_notify)(const struct path *path, u64 mask,
+ unsigned int obj_type);
int (*inode_alloc_security)(struct inode *inode);
void (*inode_free_security)(struct inode *inode);
int (*inode_init_security)(struct inode *inode, struct inode *dir,
@@ -1860,6 +1865,8 @@ struct security_hook_heads {
struct hlist_head path_chown;
struct hlist_head path_chroot;
#endif
+ /* Needed for inode based modules as well */
+ struct hlist_head path_notify;
struct hlist_head inode_alloc_security;
struct hlist_head inode_free_security;
struct hlist_head inode_init_security;
diff --git a/include/linux/security.h b/include/linux/security.h
index 659071c2e57c..7d9c1da1f659 100644
--- a/include/linux/security.h
+++ b/include/linux/security.h
@@ -259,7 +259,8 @@ int security_dentry_create_files_as(struct dentry *dentry, int mode,
struct qstr *name,
const struct cred *old,
struct cred *new);
-
+int security_path_notify(const struct path *path, u64 mask,
+ unsigned int obj_type);
int security_inode_alloc(struct inode *inode);
void security_inode_free(struct inode *inode);
int security_inode_init_security(struct inode *inode, struct inode *dir,
@@ -387,7 +388,6 @@ int security_ismaclabel(const char *name);
int security_secid_to_secctx(u32 secid, char **secdata, u32 *seclen);
int security_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid);
void security_release_secctx(char *secdata, u32 seclen);
-
void security_inode_invalidate_secctx(struct inode *inode);
int security_inode_notifysecctx(struct inode *inode, void *ctx, u32 ctxlen);
int security_inode_setsecctx(struct dentry *dentry, void *ctx, u32 ctxlen);
@@ -621,6 +621,12 @@ static inline int security_move_mount(const struct path *from_path,
return 0;
}
+static inline int security_path_notify(const struct path *path, u64 mask,
+ unsigned int obj_type)
+{
+ return 0;
+}
+
static inline int security_inode_alloc(struct inode *inode)
{
return 0;
diff --git a/security/security.c b/security/security.c
index 613a5c00e602..30687e1366b7 100644
--- a/security/security.c
+++ b/security/security.c
@@ -871,6 +871,12 @@ int security_move_mount(const struct path *from_path, const struct path *to_path
return call_int_hook(move_mount, 0, from_path, to_path);
}
+int security_path_notify(const struct path *path, u64 mask,
+ unsigned int obj_type)
+{
+ return call_int_hook(path_notify, 0, path, mask, obj_type);
+}
+
int security_inode_alloc(struct inode *inode)
{
int rc = lsm_inode_alloc(inode);
diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c
index f77b314d0575..d55571c585ff 100644
--- a/security/selinux/hooks.c
+++ b/security/selinux/hooks.c
@@ -92,6 +92,8 @@
#include <linux/kernfs.h>
#include <linux/stringhash.h> /* for hashlen_string() */
#include <uapi/linux/mount.h>
+#include <linux/fsnotify.h>
+#include <linux/fanotify.h>
#include "avc.h"
#include "objsec.h"
@@ -3261,6 +3263,50 @@ static int selinux_inode_removexattr(struct dentry *dentry, const char *name)
return -EACCES;
}
+static int selinux_path_notify(const struct path *path, u64 mask,
+ unsigned int obj_type)
+{
+ int ret;
+ u32 perm;
+
+ struct common_audit_data ad;
+
+ ad.type = LSM_AUDIT_DATA_PATH;
+ ad.u.path = *path;
+
+ /*
+ * Set permission needed based on the type of mark being set.
+ * Performs an additional check for sb watches.
+ */
+ switch (obj_type) {
+ case FSNOTIFY_OBJ_TYPE_VFSMOUNT:
+ perm = FILE__WATCH_MOUNT;
+ break;
+ case FSNOTIFY_OBJ_TYPE_SB:
+ perm = FILE__WATCH_SB;
+ ret = superblock_has_perm(current_cred(), path->dentry->d_sb,
+ FILESYSTEM__WATCH, &ad);
+ if (ret)
+ return ret;
+ break;
+ case FSNOTIFY_OBJ_TYPE_INODE:
+ perm = FILE__WATCH;
+ break;
+ default:
+ return -EINVAL;
+ }
+
+ /* blocking watches require the file:watch_with_perm permission */
+ if (mask & (ALL_FSNOTIFY_PERM_EVENTS))
+ perm |= FILE__WATCH_WITH_PERM;
+
+ /* watches on read-like events need the file:watch_reads permission */
+ if (mask & (FS_ACCESS | FS_ACCESS_PERM | FS_CLOSE_NOWRITE))
+ perm |= FILE__WATCH_READS;
+
+ return path_has_perm(current_cred(), path, perm);
+}
+
/*
* Copy the inode security context value to the user.
*
@@ -6798,6 +6844,7 @@ static struct security_hook_list selinux_hooks[] __lsm_ro_after_init = {
LSM_HOOK_INIT(inode_getsecid, selinux_inode_getsecid),
LSM_HOOK_INIT(inode_copy_up, selinux_inode_copy_up),
LSM_HOOK_INIT(inode_copy_up_xattr, selinux_inode_copy_up_xattr),
+ LSM_HOOK_INIT(path_notify, selinux_path_notify),
LSM_HOOK_INIT(kernfs_init_security, selinux_kernfs_init_security),
diff --git a/security/selinux/include/classmap.h b/security/selinux/include/classmap.h
index 201f7e588a29..32e9b03be3dd 100644
--- a/security/selinux/include/classmap.h
+++ b/security/selinux/include/classmap.h
@@ -7,7 +7,8 @@
#define COMMON_FILE_PERMS COMMON_FILE_SOCK_PERMS, "unlink", "link", \
"rename", "execute", "quotaon", "mounton", "audit_access", \
- "open", "execmod"
+ "open", "execmod", "watch", "watch_mount", "watch_sb", \
+ "watch_with_perm", "watch_reads"
#define COMMON_SOCK_PERMS COMMON_FILE_SOCK_PERMS, "bind", "connect", \
"listen", "accept", "getopt", "setopt", "shutdown", "recvfrom", \
@@ -60,7 +61,7 @@ struct security_class_mapping secclass_map[] = {
{ "filesystem",
{ "mount", "remount", "unmount", "getattr",
"relabelfrom", "relabelto", "associate", "quotamod",
- "quotaget", NULL } },
+ "quotaget", "watch", NULL } },
{ "file",
{ COMMON_FILE_PERMS,
"execute_no_trans", "entrypoint", NULL } },