1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * Regression3
4 * Description:
5 * Helper radix_tree_iter_retry resets next_index to the current index.
6 * In following radix_tree_next_slot current chunk size becomes zero.
7 * This isn't checked and it tries to dereference null pointer in slot.
8 *
9 * Helper radix_tree_iter_resume reset slot to NULL and next_index to index + 1,
10 * for tagger iteraction it also must reset cached tags in iterator to abort
11 * next radix_tree_next_slot and go to slow-path into radix_tree_next_chunk.
12 *
13 * Running:
14 * This test should run to completion immediately. The above bug would
15 * cause it to segfault.
16 *
17 * Upstream commit:
18 * Not yet
19 */
20 #include <linux/kernel.h>
21 #include <linux/gfp.h>
22 #include <linux/slab.h>
23 #include <linux/radix-tree.h>
24 #include <stdlib.h>
25 #include <stdio.h>
26
27 #include "regression.h"
28
regression3_test(void)29 void regression3_test(void)
30 {
31 RADIX_TREE(root, GFP_KERNEL);
32 void *ptr0 = (void *)4ul;
33 void *ptr = (void *)8ul;
34 struct radix_tree_iter iter;
35 void **slot;
36 bool first;
37
38 printv(1, "running regression test 3 (should take milliseconds)\n");
39
40 radix_tree_insert(&root, 0, ptr0);
41 radix_tree_tag_set(&root, 0, 0);
42
43 first = true;
44 radix_tree_for_each_tagged(slot, &root, &iter, 0, 0) {
45 printv(2, "tagged %ld %p\n", iter.index, *slot);
46 if (first) {
47 radix_tree_insert(&root, 1, ptr);
48 radix_tree_tag_set(&root, 1, 0);
49 first = false;
50 }
51 if (radix_tree_deref_retry(*slot)) {
52 printv(2, "retry at %ld\n", iter.index);
53 slot = radix_tree_iter_retry(&iter);
54 continue;
55 }
56 }
57 radix_tree_delete(&root, 1);
58
59 first = true;
60 radix_tree_for_each_slot(slot, &root, &iter, 0) {
61 printv(2, "slot %ld %p\n", iter.index, *slot);
62 if (first) {
63 radix_tree_insert(&root, 1, ptr);
64 first = false;
65 }
66 if (radix_tree_deref_retry(*slot)) {
67 printv(2, "retry at %ld\n", iter.index);
68 slot = radix_tree_iter_retry(&iter);
69 continue;
70 }
71 }
72
73 radix_tree_for_each_slot(slot, &root, &iter, 0) {
74 printv(2, "slot %ld %p\n", iter.index, *slot);
75 if (!iter.index) {
76 printv(2, "next at %ld\n", iter.index);
77 slot = radix_tree_iter_resume(slot, &iter);
78 }
79 }
80
81 radix_tree_tag_set(&root, 0, 0);
82 radix_tree_tag_set(&root, 1, 0);
83 radix_tree_for_each_tagged(slot, &root, &iter, 0, 0) {
84 printv(2, "tagged %ld %p\n", iter.index, *slot);
85 if (!iter.index) {
86 printv(2, "next at %ld\n", iter.index);
87 slot = radix_tree_iter_resume(slot, &iter);
88 }
89 }
90
91 radix_tree_delete(&root, 0);
92 radix_tree_delete(&root, 1);
93
94 printv(1, "regression test 3 passed\n");
95 }
96