2012-10-04 06:06:26

by Lucas De Marchi

[permalink] [raw]
Subject: [PATCH BlueZ] core: Fix walking the list while removing elements

If we are walking a GSList and remove the element we are pointing to,
the next iteration g_slist_next() will access previously freed
memory.
---

This was caught only by inspecting the code. I don't know why valgrind
didn't complain about accessing previously freed memory region.

src/device.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/src/device.c b/src/device.c
index c659164..6150963 100644
--- a/src/device.c
+++ b/src/device.c
@@ -1498,7 +1498,7 @@ static void device_remove_profiles(struct btd_device *device, GSList *uuids)
if (records)
sdp_list_free(records, (sdp_free_func_t) sdp_record_free);

- for (l = device->profiles; l != NULL; l = g_slist_next(l)) {
+ for (l = device->profiles; l != NULL;) {
struct btd_profile *profile = l->data;
GSList *probe_uuids;

@@ -1506,9 +1506,11 @@ static void device_remove_profiles(struct btd_device *device, GSList *uuids)
device->uuids);
if (probe_uuids != NULL) {
g_slist_free(probe_uuids);
+ l = l->next;
continue;
}

+ l = l->next;
profile->device_remove(profile, device);
device->profiles = g_slist_remove(device->profiles, profile);
}
--
1.7.12.2