From 041b78f232bb87b2de8ca3fed50384bc7dc9c2de Mon Sep 17 00:00:00 2001 From: Artem Bityutskiy Date: Tue, 26 Oct 2010 14:23:08 -0700 Subject: [PATCH] lib/list_sort: test: check element addresses Improve 'lib_sort()' test and check that: o 'cmp()' is called only for elements which were present in the original list, i.e., the 'a' and 'b' parameters are valid o the resulted (sorted) list consists onlly of the original elements o intdoruce "poison" fields to make sure data around 'struc list_head' field are not corrupted. Signed-off-by: Artem Bityutskiy Cc: Don Mullis Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- lib/list_sort.c | 75 +++++++++++++++++++++++++++++++++++++++++++------ 1 file changed, 67 insertions(+), 8 deletions(-) diff --git a/lib/list_sort.c b/lib/list_sort.c index 01aff9e80821..d7325c6b103f 100644 --- a/lib/list_sort.c +++ b/lib/list_sort.c @@ -145,23 +145,65 @@ EXPORT_SYMBOL(list_sort); #include +/* + * The pattern of set bits in the list length determines which cases + * are hit in list_sort(). + */ +#define TEST_LIST_LEN (512+128+2) /* not including head */ + +#define TEST_POISON1 0xDEADBEEF +#define TEST_POISON2 0xA324354C + struct debug_el { + unsigned int poison1; struct list_head list; + unsigned int poison2; int value; unsigned serial; }; -static int cmp(void *priv, struct list_head *a, struct list_head *b) +/* Array, containing pointers to all elements in the test list */ +static struct debug_el **elts __initdata; + +static int __init check(struct debug_el *ela, struct debug_el *elb) { - return container_of(a, struct debug_el, list)->value - - container_of(b, struct debug_el, list)->value; + if (ela->serial >= TEST_LIST_LEN) { + printk(KERN_ERR "list_sort_test: error: incorrect serial %d\n", + ela->serial); + return -EINVAL; + } + if (elb->serial >= TEST_LIST_LEN) { + printk(KERN_ERR "list_sort_test: error: incorrect serial %d\n", + elb->serial); + return -EINVAL; + } + if (elts[ela->serial] != ela || elts[elb->serial] != elb) { + printk(KERN_ERR "list_sort_test: error: phantom element\n"); + return -EINVAL; + } + if (ela->poison1 != TEST_POISON1 || ela->poison2 != TEST_POISON2) { + printk(KERN_ERR "list_sort_test: error: bad poison: %#x/%#x\n", + ela->poison1, ela->poison2); + return -EINVAL; + } + if (elb->poison1 != TEST_POISON1 || elb->poison2 != TEST_POISON2) { + printk(KERN_ERR "list_sort_test: error: bad poison: %#x/%#x\n", + elb->poison1, elb->poison2); + return -EINVAL; + } + return 0; } -/* - * The pattern of set bits in the list length determines which cases - * are hit in list_sort(). - */ -#define TEST_LIST_LEN (512+128+2) /* not including head */ +static int __init cmp(void *priv, struct list_head *a, struct list_head *b) +{ + struct debug_el *ela, *elb; + + ela = container_of(a, struct debug_el, list); + elb = container_of(b, struct debug_el, list); + + check(ela, elb); + return ela->value - elb->value; +} static int __init list_sort_test(void) { @@ -172,6 +214,13 @@ static int __init list_sort_test(void) printk(KERN_DEBUG "list_sort_test: start testing list_sort()\n"); + elts = kmalloc(sizeof(void *) * TEST_LIST_LEN, GFP_KERNEL); + if (!elts) { + printk(KERN_ERR "list_sort_test: error: cannot allocate " + "memory\n"); + goto exit; + } + for (i = 0; i < TEST_LIST_LEN; i++) { el = kmalloc(sizeof(*el), GFP_KERNEL); if (!el) { @@ -182,6 +231,9 @@ static int __init list_sort_test(void) /* force some equivalencies */ el->value = random32() % (TEST_LIST_LEN/3); el->serial = i; + el->poison1 = TEST_POISON1; + el->poison2 = TEST_POISON2; + elts[i] = el; list_add_tail(&el->list, &head); } @@ -211,6 +263,12 @@ static int __init list_sort_test(void) "equivalent elements not preserved\n"); goto exit; } + + if (check(el, el1)) { + printk(KERN_ERR "list_sort_test: error: element check " + "failed\n"); + goto exit; + } count++; } @@ -222,6 +280,7 @@ static int __init list_sort_test(void) err = 0; exit: + kfree(elts); list_for_each_safe(cur, tmp, &head) { list_del(cur); kfree(container_of(cur, struct debug_el, list)); -- 2.20.1