diff options
Diffstat (limited to 'security/device_cgroup.c')
-rw-r--r-- | security/device_cgroup.c | 92 |
1 files changed, 25 insertions, 67 deletions
diff --git a/security/device_cgroup.c b/security/device_cgroup.c index 03c1652c9a1f..c65b39bafdfe 100644 --- a/security/device_cgroup.c +++ b/security/device_cgroup.c @@ -1,3 +1,4 @@ +// SPDX-License-Identifier: GPL-2.0 /* * device_cgroup.c - device cgroup subsystem * @@ -14,15 +15,6 @@ #include <linux/rcupdate.h> #include <linux/mutex.h> -#define ACC_MKNOD 1 -#define ACC_READ 2 -#define ACC_WRITE 4 -#define ACC_MASK (ACC_MKNOD | ACC_READ | ACC_WRITE) - -#define DEV_BLOCK 1 -#define DEV_CHAR 2 -#define DEV_ALL 4 /* this represents all devices */ - static DEFINE_MUTEX(devcgroup_mutex); enum devcg_behavior { @@ -245,21 +237,21 @@ static void set_access(char *acc, short access) { int idx = 0; memset(acc, 0, ACCLEN); - if (access & ACC_READ) + if (access & DEVCG_ACC_READ) acc[idx++] = 'r'; - if (access & ACC_WRITE) + if (access & DEVCG_ACC_WRITE) acc[idx++] = 'w'; - if (access & ACC_MKNOD) + if (access & DEVCG_ACC_MKNOD) acc[idx++] = 'm'; } static char type_to_char(short type) { - if (type == DEV_ALL) + if (type == DEVCG_DEV_ALL) return 'a'; - if (type == DEV_CHAR) + if (type == DEVCG_DEV_CHAR) return 'c'; - if (type == DEV_BLOCK) + if (type == DEVCG_DEV_BLOCK) return 'b'; return 'X'; } @@ -286,10 +278,10 @@ static int devcgroup_seq_show(struct seq_file *m, void *v) * This way, the file remains as a "whitelist of devices" */ if (devcgroup->behavior == DEVCG_DEFAULT_ALLOW) { - set_access(acc, ACC_MASK); + set_access(acc, DEVCG_ACC_MASK); set_majmin(maj, ~0); set_majmin(min, ~0); - seq_printf(m, "%c %s:%s %s\n", type_to_char(DEV_ALL), + seq_printf(m, "%c %s:%s %s\n", type_to_char(DEVCG_DEV_ALL), maj, min, acc); } else { list_for_each_entry_rcu(ex, &devcgroup->exceptions, list) { @@ -308,10 +300,10 @@ static int devcgroup_seq_show(struct seq_file *m, void *v) /** * match_exception - iterates the exception list trying to find a complete match * @exceptions: list of exceptions - * @type: device type (DEV_BLOCK or DEV_CHAR) + * @type: device type (DEVCG_DEV_BLOCK or DEVCG_DEV_CHAR) * @major: device file major number, ~0 to match all * @minor: device file minor number, ~0 to match all - * @access: permission mask (ACC_READ, ACC_WRITE, ACC_MKNOD) + * @access: permission mask (DEVCG_ACC_READ, DEVCG_ACC_WRITE, DEVCG_ACC_MKNOD) * * It is considered a complete match if an exception is found that will * contain the entire range of provided parameters. @@ -324,9 +316,9 @@ static bool match_exception(struct list_head *exceptions, short type, struct dev_exception_item *ex; list_for_each_entry_rcu(ex, exceptions, list) { - if ((type & DEV_BLOCK) && !(ex->type & DEV_BLOCK)) + if ((type & DEVCG_DEV_BLOCK) && !(ex->type & DEVCG_DEV_BLOCK)) continue; - if ((type & DEV_CHAR) && !(ex->type & DEV_CHAR)) + if ((type & DEVCG_DEV_CHAR) && !(ex->type & DEVCG_DEV_CHAR)) continue; if (ex->major != ~0 && ex->major != major) continue; @@ -343,10 +335,10 @@ static bool match_exception(struct list_head *exceptions, short type, /** * match_exception_partial - iterates the exception list trying to find a partial match * @exceptions: list of exceptions - * @type: device type (DEV_BLOCK or DEV_CHAR) + * @type: device type (DEVCG_DEV_BLOCK or DEVCG_DEV_CHAR) * @major: device file major number, ~0 to match all * @minor: device file minor number, ~0 to match all - * @access: permission mask (ACC_READ, ACC_WRITE, ACC_MKNOD) + * @access: permission mask (DEVCG_ACC_READ, DEVCG_ACC_WRITE, DEVCG_ACC_MKNOD) * * It is considered a partial match if an exception's range is found to * contain *any* of the devices specified by provided parameters. This is @@ -361,9 +353,9 @@ static bool match_exception_partial(struct list_head *exceptions, short type, struct dev_exception_item *ex; list_for_each_entry_rcu(ex, exceptions, list) { - if ((type & DEV_BLOCK) && !(ex->type & DEV_BLOCK)) + if ((type & DEVCG_DEV_BLOCK) && !(ex->type & DEVCG_DEV_BLOCK)) continue; - if ((type & DEV_CHAR) && !(ex->type & DEV_CHAR)) + if ((type & DEVCG_DEV_CHAR) && !(ex->type & DEVCG_DEV_CHAR)) continue; /* * We must be sure that both the exception and the provided @@ -646,10 +638,10 @@ static int devcgroup_update_access(struct dev_cgroup *devcgroup, } return 0; case 'b': - ex.type = DEV_BLOCK; + ex.type = DEVCG_DEV_BLOCK; break; case 'c': - ex.type = DEV_CHAR; + ex.type = DEVCG_DEV_CHAR; break; default: return -EINVAL; @@ -702,13 +694,13 @@ static int devcgroup_update_access(struct dev_cgroup *devcgroup, for (b++, count = 0; count < 3; count++, b++) { switch (*b) { case 'r': - ex.access |= ACC_READ; + ex.access |= DEVCG_ACC_READ; break; case 'w': - ex.access |= ACC_WRITE; + ex.access |= DEVCG_ACC_WRITE; break; case 'm': - ex.access |= ACC_MKNOD; + ex.access |= DEVCG_ACC_MKNOD; break; case '\n': case '\0': @@ -805,12 +797,12 @@ struct cgroup_subsys devices_cgrp_subsys = { * @type: device type * @major: device major number * @minor: device minor number - * @access: combination of ACC_WRITE, ACC_READ and ACC_MKNOD + * @access: combination of DEVCG_ACC_WRITE, DEVCG_ACC_READ and DEVCG_ACC_MKNOD * * returns 0 on success, -EPERM case the operation is not permitted */ -static int __devcgroup_check_permission(short type, u32 major, u32 minor, - short access) +int __devcgroup_check_permission(short type, u32 major, u32 minor, + short access) { struct dev_cgroup *dev_cgroup; bool rc; @@ -832,37 +824,3 @@ static int __devcgroup_check_permission(short type, u32 major, u32 minor, return 0; } - -int __devcgroup_inode_permission(struct inode *inode, int mask) -{ - short type, access = 0; - - if (S_ISBLK(inode->i_mode)) - type = DEV_BLOCK; - if (S_ISCHR(inode->i_mode)) - type = DEV_CHAR; - if (mask & MAY_WRITE) - access |= ACC_WRITE; - if (mask & MAY_READ) - access |= ACC_READ; - - return __devcgroup_check_permission(type, imajor(inode), iminor(inode), - access); -} - -int devcgroup_inode_mknod(int mode, dev_t dev) -{ - short type; - - if (!S_ISBLK(mode) && !S_ISCHR(mode)) - return 0; - - if (S_ISBLK(mode)) - type = DEV_BLOCK; - else - type = DEV_CHAR; - - return __devcgroup_check_permission(type, MAJOR(dev), MINOR(dev), - ACC_MKNOD); - -} |