diff options
Diffstat (limited to 'security/device_cgroup.c')
| -rw-r--r-- | security/device_cgroup.c | 44 |
1 files changed, 31 insertions, 13 deletions
diff --git a/security/device_cgroup.c b/security/device_cgroup.c index 4ea583689eec..ddd92cec78ed 100644 --- a/security/device_cgroup.c +++ b/security/device_cgroup.c @@ -49,10 +49,14 @@ struct dev_cgroup { spinlock_t lock; }; +static inline struct dev_cgroup *css_to_devcgroup(struct cgroup_subsys_state *s) +{ + return container_of(s, struct dev_cgroup, css); +} + static inline struct dev_cgroup *cgroup_to_devcgroup(struct cgroup *cgroup) { - return container_of(cgroup_subsys_state(cgroup, devices_subsys_id), - struct dev_cgroup, css); + return css_to_devcgroup(cgroup_subsys_state(cgroup, devices_subsys_id)); } struct cgroup_subsys devices_subsys; @@ -102,7 +106,7 @@ free_and_exit: static int dev_whitelist_add(struct dev_cgroup *dev_cgroup, struct dev_whitelist_item *wh) { - struct dev_whitelist_item *whcopy; + struct dev_whitelist_item *whcopy, *walk; whcopy = kmalloc(sizeof(*whcopy), GFP_KERNEL); if (!whcopy) @@ -110,7 +114,21 @@ static int dev_whitelist_add(struct dev_cgroup *dev_cgroup, memcpy(whcopy, wh, sizeof(*whcopy)); spin_lock(&dev_cgroup->lock); - list_add_tail(&whcopy->list, &dev_cgroup->whitelist); + list_for_each_entry(walk, &dev_cgroup->whitelist, list) { + if (walk->type != wh->type) + continue; + if (walk->major != wh->major) + continue; + if (walk->minor != wh->minor) + continue; + + walk->access |= wh->access; + kfree(whcopy); + whcopy = NULL; + } + + if (whcopy != NULL) + list_add_tail(&whcopy->list, &dev_cgroup->whitelist); spin_unlock(&dev_cgroup->lock); return 0; } @@ -204,7 +222,7 @@ static void devcgroup_destroy(struct cgroup_subsys *ss, #define DEVCG_DENY 2 #define DEVCG_LIST 3 -#define MAJMINLEN 10 +#define MAJMINLEN 13 #define ACCLEN 4 static void set_access(char *acc, short access) @@ -236,7 +254,7 @@ static void set_majmin(char *str, unsigned m) if (m == ~0) sprintf(str, "*"); else - snprintf(str, MAJMINLEN, "%d", m); + snprintf(str, MAJMINLEN, "%u", m); } static int devcgroup_seq_read(struct cgroup *cgroup, struct cftype *cft, @@ -282,7 +300,7 @@ static int may_access_whitelist(struct dev_cgroup *c, continue; if (whitem->minor != ~0 && whitem->minor != refwh->minor) continue; - if (refwh->access & (~(whitem->access | ACC_MASK))) + if (refwh->access & (~whitem->access)) continue; return 1; } @@ -364,6 +382,8 @@ static ssize_t devcgroup_access_write(struct cgroup *cgroup, struct cftype *cft, case 'a': wh.type = DEV_ALL; wh.access = ACC_MASK; + wh.major = ~0; + wh.minor = ~0; goto handle; case 'b': wh.type = DEV_BLOCK; @@ -502,7 +522,6 @@ struct cgroup_subsys devices_subsys = { int devcgroup_inode_permission(struct inode *inode, int mask) { - struct cgroup *cgroup; struct dev_cgroup *dev_cgroup; struct dev_whitelist_item *wh; @@ -511,8 +530,8 @@ int devcgroup_inode_permission(struct inode *inode, int mask) return 0; if (!S_ISBLK(inode->i_mode) && !S_ISCHR(inode->i_mode)) return 0; - cgroup = task_cgroup(current, devices_subsys.subsys_id); - dev_cgroup = cgroup_to_devcgroup(cgroup); + dev_cgroup = css_to_devcgroup(task_subsys_state(current, + devices_subsys_id)); if (!dev_cgroup) return 0; @@ -543,12 +562,11 @@ acc_check: int devcgroup_inode_mknod(int mode, dev_t dev) { - struct cgroup *cgroup; struct dev_cgroup *dev_cgroup; struct dev_whitelist_item *wh; - cgroup = task_cgroup(current, devices_subsys.subsys_id); - dev_cgroup = cgroup_to_devcgroup(cgroup); + dev_cgroup = css_to_devcgroup(task_subsys_state(current, + devices_subsys_id)); if (!dev_cgroup) return 0; |