linux-master/kernel/seccomp.c

3  * linux/kernel/seccomp.c
16 #define pr_fmt(fmt) "seccomp: " fmt
27 #include <linux/seccomp.h>
71 	 * The seccomp data. This pointer is valid the entire time this
94 	 * dying, a new seccomp addfd message, or changing to REPLIED
138  * struct notification - container for seccomp userspace notifications. Since
139  * most seccomp filters will not have notification listeners attached and this
160  * struct action_cache - per-filter cache of seccomp actions per
191  * struct seccomp_filter - container for seccomp BPF programs
218  * with current->seccomp.filter, the most recently attached or inherited filter.
269  *	seccomp_check_filter - verify seccomp filter code
363  * seccomp_cache_check_allow - lookup seccomp cache
364  * @sfilter: The seccomp filter
365  * @sd: The seccomp data to lookup the cache with
398  * seccomp_run_filters - evaluates all seccomp filters against @sd
399  * @sd: optional seccomp data to be passed to filters
404  * Returns valid seccomp BPF response codes.
412 			READ_ONCE(current->seccomp.filter);
441 	if (current->seccomp.mode && current->seccomp.mode != seccomp_mode)
455 	task->seccomp.mode = seccomp_mode;
461 	/* Assume default seccomp processes want spec flaw mitigation. */
487  * either not in the correct seccomp mode or did not have an ancestral
488  * seccomp filter.
506 		if (thread->seccomp.mode == SECCOMP_MODE_DISABLED ||
507 		    (thread->seccomp.mode == SECCOMP_MODE_FILTER &&
508 		     is_ancestor(thread->seccomp.filter,
509 				 caller->seccomp.filter)))
571 	struct seccomp_filter *orig = tsk->seccomp.filter;
577 	tsk->seccomp.filter = NULL;
613 		__seccomp_filter_release(thread->seccomp.filter);
616 		smp_store_release(&thread->seccomp.filter,
617 				  caller->seccomp.filter);
618 		atomic_set(&thread->seccomp.filter_count,
619 			   atomic_read(&caller->seccomp.filter_count));
624 		 * a thread that sets it up, enters seccomp,
631 		 * Opt the other thread into seccomp if needed.
636 		if (thread->seccomp.mode == SECCOMP_MODE_DISABLED)
643  * seccomp_prepare_filter: Prepares a seccomp filter for use.
665 	 * Installing a seccomp filter requires that the task has
726  * @sd: The seccomp data to check against, only syscall number and arch
840  * @sfilter: The seccomp filter
867  * @filter: seccomp filter to add to the current process
873  *     seccomp mode or did not have an ancestral seccomp filter
886 	for (walker = current->seccomp.filter; walker; walker = walker->prev)
916 	filter->prev = current->seccomp.filter;
918 	current->seccomp.filter = filter;
919 	atomic_inc(&current->seccomp.filter_count);
936 	struct seccomp_filter *orig = tsk->seccomp.filter;
1031 	current->seccomp.mode = SECCOMP_MODE_DEAD;
1039 	int mode = current->seccomp.mode;
1306 		current->seccomp.mode = SECCOMP_MODE_DEAD;
1339 	int mode = current->seccomp.mode;
1368 	return current->seccomp.mode;
1372  * seccomp_set_mode_strict: internal function for setting strict seccomp
1374  * Once current->seccomp.mode is non-zero, it may not be changed.
1848 	ret = anon_inode_getfile("seccomp notify", &seccomp_notify_ops,
1869  * we use current->seccomp.filter.
1880 	for (cur = current->seccomp.filter; cur; cur = cur->prev) {
1889  * seccomp_set_mode_filter: internal function for setting seccomp filter
1897  * Once current->seccomp.mode is non-zero, it may not be changed.
1955 	 * Make sure we cannot change seccomp or nnp state via TSYNC
2071 SYSCALL_DEFINE3(seccomp, unsigned int, op, unsigned int, flags,
2078  * prctl_set_seccomp: configures current->seccomp.mode
2124 	if (task->seccomp.mode != SECCOMP_MODE_FILTER) {
2129 	orig = task->seccomp.filter;
2166 	    current->seccomp.mode != SECCOMP_MODE_DISABLED) {
2204 	    current->seccomp.mode != SECCOMP_MODE_DISABLED) {
2452 	register_sysctl_init("kernel/seccomp", seccomp_sysctl_table);
2482 	 * We don't want some sandboxed process to know what their seccomp
2491 	f = READ_ONCE(task->seccomp.filter);