mirror of
https://github.com/SELinuxProject/selinux
synced 2024-12-16 19:24:35 +00:00
libsepol/cil: improve recursion detection
Add support for detecting recursive blockinherits, and print a trace of
the detected loop. Output will look something like this upon detection:
Recursive blockinherit found:
test.cil:42: block a
test.cil:43: blockinherit b
test.cil:36: block b
test.cil:37: blockinherit c
test.cil:39: block c
test.cil:40: blockinherit a
Additionally, improve support for detecting recursive macros/calls. Due
to the way calls are copied, the existing code only detected recursion
with call depth of three or more. Smaller depths, like
(macro m ()
(call m))
were not detected and caused a segfault. The callstack that was used for
this was not sufficient, so that is removed and replaced with a method
similar to the block recursion detection. A similar trace is also
displayed for recursive macros/calls.
Also, cleanup sidorder, classorder, catorder, sensorder, and in lists at
the end of resolve, fixing a potential memory leak if errors occur
during resolve.
Signed-off-by: Steve Lawrence <slawrence@tresys.com>
Signed-off-by: James Carter <jwcart2@tycho.nsa.gov>
This commit is contained in:
Steve Lawrence
James Carter
parent
3302de4625
commit
551d834c39
@ -52,7 +52,6 @@ struct cil_args_resolve {
|
||||
enum cil_pass pass;
|
||||
uint32_t *changed;
|
||||
char *last_resolved_name;
|
||||
struct cil_tree_node *callstack;
|
||||
struct cil_tree_node *optstack;
|
||||
struct cil_tree_node *boolif;
|
||||
struct cil_tree_node *macro;
|
||||
@ -2210,6 +2209,73 @@ exit:
|
||||
return rc;
|
||||
}
|
||||
|
||||
void cil_print_recursive_blockinherit(struct cil_tree_node *bi_node, struct cil_tree_node *terminating_node)
|
||||
{
|
||||
struct cil_list *trace = NULL;
|
||||
struct cil_list_item *item = NULL;
|
||||
struct cil_tree_node *curr = NULL;
|
||||
|
||||
cil_list_init(&trace, CIL_NODE);
|
||||
|
||||
for (curr = bi_node; curr != terminating_node; curr = curr->parent) {
|
||||
if (curr->flavor == CIL_BLOCK) {
|
||||
cil_list_prepend(trace, CIL_NODE, curr);
|
||||
} else {
|
||||
if (curr != bi_node) {
|
||||
cil_list_prepend(trace, CIL_NODE, NODE(((struct cil_blockinherit *)curr->data)->block));
|
||||
}
|
||||
cil_list_prepend(trace, CIL_NODE, curr);
|
||||
}
|
||||
}
|
||||
cil_list_prepend(trace, CIL_NODE, terminating_node);
|
||||
|
||||
cil_list_for_each(item, trace) {
|
||||
curr = item->data;
|
||||
cil_log(CIL_ERR, " %s:%d: ", curr->path, curr->line);
|
||||
|
||||
if (curr->flavor == CIL_BLOCK) {
|
||||
cil_log(CIL_ERR, "block %s\n", DATUM(curr->data)->name);
|
||||
} else {
|
||||
cil_log(CIL_ERR, "blockinherit %s\n", ((struct cil_blockinherit *)curr->data)->block_str);
|
||||
}
|
||||
}
|
||||
|
||||
cil_list_destroy(&trace, CIL_FALSE);
|
||||
}
|
||||
|
||||
int cil_check_recursive_blockinherit(struct cil_tree_node *bi_node)
|
||||
{
|
||||
struct cil_tree_node *curr = NULL;
|
||||
struct cil_blockinherit *bi = NULL;
|
||||
struct cil_block *block = NULL;
|
||||
int rc = SEPOL_ERR;
|
||||
|
||||
bi = bi_node->data;
|
||||
|
||||
for (curr = bi_node->parent; curr != NULL; curr = curr->parent) {
|
||||
if (curr->flavor != CIL_BLOCK) {
|
||||
continue;
|
||||
}
|
||||
|
||||
block = curr->data;
|
||||
|
||||
if (block != bi->block) {
|
||||
continue;
|
||||
}
|
||||
|
||||
cil_log(CIL_ERR, "Recursive blockinherit found:\n");
|
||||
cil_print_recursive_blockinherit(bi_node, curr);
|
||||
|
||||
rc = SEPOL_ERR;
|
||||
goto exit;
|
||||
}
|
||||
|
||||
rc = SEPOL_OK;
|
||||
|
||||
exit:
|
||||
return rc;
|
||||
}
|
||||
|
||||
int cil_resolve_blockinherit_copy(struct cil_tree_node *current, void *extra_args)
|
||||
{
|
||||
struct cil_block *block = current->data;
|
||||
@ -2233,6 +2299,11 @@ int cil_resolve_blockinherit_copy(struct cil_tree_node *current, void *extra_arg
|
||||
}
|
||||
|
||||
cil_list_for_each(item, block->bi_nodes) {
|
||||
rc = cil_check_recursive_blockinherit(item->data);
|
||||
if (rc != SEPOL_OK) {
|
||||
goto exit;
|
||||
}
|
||||
|
||||
rc = cil_copy_ast(db, current, item->data);
|
||||
if (rc != SEPOL_OK) {
|
||||
cil_log(CIL_ERR, "Failed to copy block contents into blockinherit\n");
|
||||
@ -2500,6 +2571,80 @@ exit:
|
||||
return rc;
|
||||
}
|
||||
|
||||
void cil_print_recursive_call(struct cil_tree_node *call_node, struct cil_tree_node *terminating_node)
|
||||
{
|
||||
struct cil_list *trace = NULL;
|
||||
struct cil_list_item * item = NULL;
|
||||
struct cil_tree_node *curr = NULL;
|
||||
|
||||
cil_list_init(&trace, CIL_NODE);
|
||||
|
||||
for (curr = call_node; curr != terminating_node; curr = curr->parent) {
|
||||
if (curr->flavor == CIL_CALL) {
|
||||
if (curr != call_node) {
|
||||
cil_list_prepend(trace, CIL_NODE, NODE(((struct cil_call *)curr->data)->macro));
|
||||
}
|
||||
cil_list_prepend(trace, CIL_NODE, curr);
|
||||
}
|
||||
}
|
||||
|
||||
if (terminating_node->flavor == CIL_MACRO) {
|
||||
cil_list_prepend(trace, CIL_NODE, terminating_node);
|
||||
} else {
|
||||
cil_list_prepend(trace, CIL_NODE, NODE(((struct cil_call *)terminating_node->data)->macro));
|
||||
}
|
||||
|
||||
cil_list_for_each(item, trace) {
|
||||
curr = item->data;
|
||||
cil_log(CIL_ERR, " %s:%d: ", curr->path, curr->line);
|
||||
|
||||
if (curr->flavor == CIL_MACRO) {
|
||||
cil_log(CIL_ERR, "macro %s\n", DATUM(curr->data)->name);
|
||||
} else {
|
||||
cil_log(CIL_ERR, "call %s\n", ((struct cil_call *)curr->data)->macro_str);
|
||||
}
|
||||
}
|
||||
|
||||
cil_list_destroy(&trace, CIL_FALSE);
|
||||
}
|
||||
|
||||
int cil_check_recursive_call(struct cil_tree_node *call_node, struct cil_tree_node *macro_node)
|
||||
{
|
||||
struct cil_tree_node *curr = NULL;
|
||||
struct cil_call * call = NULL;
|
||||
int rc = SEPOL_ERR;
|
||||
|
||||
for (curr = call_node; curr != NULL; curr = curr->parent) {
|
||||
if (curr->flavor == CIL_CALL) {
|
||||
if (curr == call_node) {
|
||||
continue;
|
||||
}
|
||||
|
||||
call = curr->data;
|
||||
if (call->macro != macro_node->data) {
|
||||
continue;
|
||||
}
|
||||
} else if (curr->flavor == CIL_MACRO) {
|
||||
if (curr != macro_node) {
|
||||
rc = SEPOL_OK;
|
||||
goto exit;
|
||||
}
|
||||
} else {
|
||||
continue;
|
||||
}
|
||||
|
||||
cil_log(CIL_ERR, "Recursive macro call found:\n");
|
||||
cil_print_recursive_call(call_node, curr);
|
||||
|
||||
rc = SEPOL_ERR;
|
||||
goto exit;
|
||||
}
|
||||
|
||||
rc = SEPOL_OK;
|
||||
exit:
|
||||
return rc;
|
||||
}
|
||||
|
||||
int cil_resolve_call1(struct cil_tree_node *current, void *extra_args)
|
||||
{
|
||||
struct cil_call *new_call = current->data;
|
||||
@ -2736,6 +2881,12 @@ int cil_resolve_call1(struct cil_tree_node *current, void *extra_args)
|
||||
|
||||
if (new_call->copied == 0) {
|
||||
new_call->copied = 1;
|
||||
|
||||
rc = cil_check_recursive_call(current, macro_node);
|
||||
if (rc != SEPOL_OK) {
|
||||
goto exit;
|
||||
}
|
||||
|
||||
rc = cil_copy_ast(db, macro_node, current);
|
||||
if (rc != SEPOL_OK) {
|
||||
cil_log(CIL_ERR, "Failed to copy macro, rc: %d\n", rc);
|
||||
@ -3509,7 +3660,6 @@ int __cil_resolve_ast_first_child_helper(struct cil_tree_node *current, void *ex
|
||||
{
|
||||
int rc = SEPOL_ERR;
|
||||
struct cil_args_resolve *args = extra_args;
|
||||
struct cil_tree_node *callstack = NULL;
|
||||
struct cil_tree_node *optstack = NULL;
|
||||
struct cil_tree_node *parent = NULL;
|
||||
struct cil_tree_node *blockstack = NULL;
|
||||
@ -3519,36 +3669,18 @@ int __cil_resolve_ast_first_child_helper(struct cil_tree_node *current, void *ex
|
||||
goto exit;
|
||||
}
|
||||
|
||||
callstack = args->callstack;
|
||||
optstack = args->optstack;
|
||||
parent = current->parent;
|
||||
blockstack = args->blockstack;
|
||||
|
||||
if (parent->flavor == CIL_CALL || parent->flavor == CIL_OPTIONAL || parent->flavor == CIL_BLOCK) {
|
||||
if (parent->flavor == CIL_OPTIONAL || parent->flavor == CIL_BLOCK) {
|
||||
/* push this node onto a stack */
|
||||
cil_tree_node_init(&new);
|
||||
|
||||
new->data = parent->data;
|
||||
new->flavor = parent->flavor;
|
||||
|
||||
if (parent->flavor == CIL_CALL) {
|
||||
if (callstack != NULL) {
|
||||
struct cil_tree_node *curr = NULL;
|
||||
struct cil_call *new_call = new->data;
|
||||
for (curr = callstack->cl_head; curr != NULL;
|
||||
curr = curr->cl_head) {
|
||||
struct cil_call *curr_call = curr->data;
|
||||
if (curr_call->macro == new_call->macro) {
|
||||
cil_log(CIL_ERR, "Recursive macro call found\n");
|
||||
rc = SEPOL_ERR;
|
||||
goto exit;
|
||||
}
|
||||
}
|
||||
callstack->parent = new;
|
||||
new->cl_head = callstack;
|
||||
}
|
||||
args->callstack = new;
|
||||
} else if (parent->flavor == CIL_OPTIONAL) {
|
||||
if (parent->flavor == CIL_OPTIONAL) {
|
||||
if (optstack != NULL) {
|
||||
optstack->parent = new;
|
||||
new->cl_head = optstack;
|
||||
@ -3587,15 +3719,7 @@ int __cil_resolve_ast_last_child_helper(struct cil_tree_node *current, void *ext
|
||||
|
||||
parent = current->parent;
|
||||
|
||||
if (parent->flavor == CIL_CALL) {
|
||||
/* pop off the stack */
|
||||
struct cil_tree_node *callstack = args->callstack;
|
||||
args->callstack = callstack->cl_head;
|
||||
if (callstack->cl_head) {
|
||||
callstack->cl_head->parent = NULL;
|
||||
}
|
||||
free(callstack);
|
||||
} else if (parent->flavor == CIL_MACRO) {
|
||||
if (parent->flavor == CIL_MACRO) {
|
||||
args->macro = NULL;
|
||||
} else if (parent->flavor == CIL_OPTIONAL) {
|
||||
struct cil_tree_node *optstack;
|
||||
@ -3645,7 +3769,6 @@ int cil_resolve_ast(struct cil_db *db, struct cil_tree_node *current)
|
||||
extra_args.pass = pass;
|
||||
extra_args.changed = &changed;
|
||||
extra_args.last_resolved_name = NULL;
|
||||
extra_args.callstack = NULL;
|
||||
extra_args.optstack = NULL;
|
||||
extra_args.boolif= NULL;
|
||||
extra_args.macro = NULL;
|
||||
@ -3737,12 +3860,6 @@ int cil_resolve_ast(struct cil_db *db, struct cil_tree_node *current)
|
||||
|
||||
/* reset the arguments */
|
||||
changed = 0;
|
||||
while (extra_args.callstack != NULL) {
|
||||
struct cil_tree_node *curr = extra_args.callstack;
|
||||
struct cil_tree_node *next = curr->cl_head;
|
||||
free(curr);
|
||||
extra_args.callstack = next;
|
||||
}
|
||||
while (extra_args.optstack != NULL) {
|
||||
struct cil_tree_node *curr = extra_args.optstack;
|
||||
struct cil_tree_node *next = curr->cl_head;
|
||||
@ -3764,6 +3881,12 @@ int cil_resolve_ast(struct cil_db *db, struct cil_tree_node *current)
|
||||
|
||||
rc = SEPOL_OK;
|
||||
exit:
|
||||
__cil_ordered_lists_destroy(&extra_args.sidorder_lists);
|
||||
__cil_ordered_lists_destroy(&extra_args.classorder_lists);
|
||||
__cil_ordered_lists_destroy(&extra_args.catorder_lists);
|
||||
__cil_ordered_lists_destroy(&extra_args.sensitivityorder_lists);
|
||||
cil_list_destroy(&extra_args.in_list, CIL_FALSE);
|
||||
|
||||
return rc;
|
||||
}
|
||||
|
||||
|
||||
Loading…
Reference in New Issue
Block a user