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authorMatthew Wilcox <mawilcox@microsoft.com>2018-02-26 22:39:30 +0300
committerMatthew Wilcox <mawilcox@microsoft.com>2018-02-26 22:39:30 +0300
commit4b0ad07653ee94182e2d8f21404242c9e83ad0b4 (patch)
tree88d581f08d2eac9d8b5d933c2740b91003e44401 /lib
parent3d4d5d618639c3155cfce57101d619a0935434d2 (diff)
downloadlinux-4b0ad07653ee94182e2d8f21404242c9e83ad0b4.tar.xz
idr: Fix handling of IDs above INT_MAX
Khalid reported that the kernel selftests are currently failing: selftests: test_bpf.sh ======================================== test_bpf: [FAIL] not ok 1..8 selftests: test_bpf.sh [FAIL] He bisected it to 6ce711f2750031d12cec91384ac5cfa0a485b60a ("idr: Make 1-based IDRs more efficient"). The root cause is doing a signed comparison in idr_alloc_u32() instead of an unsigned comparison. I went looking for any similar problems and found a couple (which would each result in the failure to warn in two situations that aren't supposed to happen). I knocked up a few test-cases to prove that I was right and added them to the test-suite. Reported-by: Khalid Aziz <khalid.aziz@oracle.com> Tested-by: Khalid Aziz <khalid.aziz@oracle.com> Signed-off-by: Matthew Wilcox <mawilcox@microsoft.com>
Diffstat (limited to 'lib')
-rw-r--r--lib/idr.c13
1 files changed, 7 insertions, 6 deletions
diff --git a/lib/idr.c b/lib/idr.c
index 99ec5bc89d25..823b813f08f8 100644
--- a/lib/idr.c
+++ b/lib/idr.c
@@ -36,8 +36,8 @@ int idr_alloc_u32(struct idr *idr, void *ptr, u32 *nextid,
{
struct radix_tree_iter iter;
void __rcu **slot;
- int base = idr->idr_base;
- int id = *nextid;
+ unsigned int base = idr->idr_base;
+ unsigned int id = *nextid;
if (WARN_ON_ONCE(radix_tree_is_internal_node(ptr)))
return -EINVAL;
@@ -204,10 +204,11 @@ int idr_for_each(const struct idr *idr,
radix_tree_for_each_slot(slot, &idr->idr_rt, &iter, 0) {
int ret;
+ unsigned long id = iter.index + base;
- if (WARN_ON_ONCE(iter.index > INT_MAX))
+ if (WARN_ON_ONCE(id > INT_MAX))
break;
- ret = fn(iter.index + base, rcu_dereference_raw(*slot), data);
+ ret = fn(id, rcu_dereference_raw(*slot), data);
if (ret)
return ret;
}
@@ -230,8 +231,8 @@ void *idr_get_next(struct idr *idr, int *nextid)
{
struct radix_tree_iter iter;
void __rcu **slot;
- int base = idr->idr_base;
- int id = *nextid;
+ unsigned long base = idr->idr_base;
+ unsigned long id = *nextid;
id = (id < base) ? 0 : id - base;
slot = radix_tree_iter_find(&idr->idr_rt, &iter, id);