| Message ID | 20210128063901.1362-1-sonnysasaka@chromium.org (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | [BlueZ,v2] input/hog: Fix crashes of UAF of hog->attr | expand |
Hi Sonny, On Wed, Jan 27, 2021 at 10:43 PM Sonny Sasaka <sonnysasaka@chromium.org> wrote: > > hog->attr does not own pointer, so it may be invalid when hog object > gets re-attached at bt_hog_attach(). To solve this, this patch > intentionally clears hog->attr at bt_hog_detach() to mark it as invalid > so that it can be repopulated with the valid pointer at bt_hog_attach(). > The same applies to all sub-instances. > > Sample stack trace: > * thread #1, stop reason = signal SIGSEGV > * frame #0: 0x05ad49f2 bluetoothd`<name omitted> at gatt-db.c:1428 > frame #1: 0x05a91922 bluetoothd`bt_hog_attach at hog-lib.c:1694 > frame #2: 0x05a9160e bluetoothd`hog_accept at hog.c:212 > frame #3: 0x05ab4784 bluetoothd`service_accept at service.c:203 > frame #4: 0x05aba1e6 bluetoothd`device_attach_att at device.c:4542 > frame #5: 0x05a9c4a2 bluetoothd`connect_cb at gatt-database.c:656 > frame #6: 0x05a98e8c bluetoothd`server_cb at btio.c:264 > frame #7: 0xec8e6a1a libglib-2.0.so.0`g_main_context_dispatch at gmain.c:3325 > frame #8: 0xec8e6c58 libglib-2.0.so.0`g_main_context_iterate at gmain.c:4119 > frame #9: 0xec8e6e52 libglib-2.0.so.0`g_main_loop_run at gmain.c:4317 > frame #10: 0x05ad582e bluetoothd`mainloop_run at mainloop-glib.c:79 > frame #11: 0x05ad5a64 bluetoothd`mainloop_run_with_signal at mainloop-notify.c:201 > frame #12: 0x05ac35ac bluetoothd`main at main.c:1103 > frame #13: 0xec6ed0a2 libc.so.6`__libc_start_main at libc-start.c:308 > > --- > profiles/input/hog-lib.c | 16 ++++++++++++++++ > 1 file changed, 16 insertions(+) > > diff --git a/profiles/input/hog-lib.c b/profiles/input/hog-lib.c > index 1f132aa4c..711bda73c 100644 > --- a/profiles/input/hog-lib.c > +++ b/profiles/input/hog-lib.c > @@ -1651,12 +1651,19 @@ static void primary_cb(uint8_t status, GSList *services, void *user_data) > bool bt_hog_attach(struct bt_hog *hog, void *gatt) > { > GSList *l; > + bt_uuid_t uuid; > > if (hog->attrib) > return false; > > hog->attrib = g_attrib_ref(gatt); > > + if (!hog->attr && hog->gatt_db) { > + bt_uuid16_create(&uuid, HOG_UUID16); > + gatt_db_foreach_service(hog->gatt_db, &uuid, > + foreach_hog_service, hog); > + } > + > if (!hog->attr && !hog->primary) { > discover_primary(hog, hog->attrib, NULL, primary_cb, hog); > return true; > @@ -1744,6 +1751,15 @@ void bt_hog_detach(struct bt_hog *hog) > bt_hog_detach(instance); > } > > + /* hog->attr doesn't own pointer, so it may be invalid when this hog > + * object gets re-attached with bt_hog_attach(). So intentionally mark > + * it as invalid and remove all instances so that the instances can be > + * re-attached at bt_hog_attach(). > + */ > + hog->attr = NULL; > + g_slist_free_full(hog->instances, hog_free); > + hog->instances = NULL; We can actually what watches instead of cleanup always like this, see: https://git.kernel.org/pub/scm/bluetooth/bluez.git/tree/src/shared/gatt-db.h#n275 > + > for (l = hog->reports; l; l = l->next) { > struct report *r = l->data; > > -- > 2.29.2 >
This is automated email and please do not reply to this email!
Dear submitter,
Thank you for submitting the patches to the linux bluetooth mailing list.
This is a CI test results with your patch series:
PW Link:https://patchwork.kernel.org/project/bluetooth/list/?series=423455
---Test result---
##############################
Test: CheckPatch - FAIL
Output:
input/hog: Fix crashes of UAF of hog->attr
WARNING:COMMIT_LOG_LONG_LINE: Possible unwrapped commit description (prefer a maximum 75 chars per line)
#21:
frame #7: 0xec8e6a1a libglib-2.0.so.0`g_main_context_dispatch at gmain.c:3325
- total: 0 errors, 1 warnings, 34 lines checked
NOTE: For some of the reported defects, checkpatch may be able to
mechanically convert to the typical style using --fix or --fix-inplace.
"[PATCH] input/hog: Fix crashes of UAF of hog->attr" has style problems, please review.
NOTE: Ignored message types: COMMIT_MESSAGE COMPLEX_MACRO CONST_STRUCT FILE_PATH_CHANGES MISSING_SIGN_OFF PREFER_PACKED SPLIT_STRING SSCANF_TO_KSTRTO
NOTE: If any of the errors are false positives, please report
them to the maintainer, see CHECKPATCH in MAINTAINERS.
##############################
Test: CheckGitLint - FAIL
Output:
input/hog: Fix crashes of UAF of hog->attr
18: B1 Line exceeds max length (81>80): " frame #7: 0xec8e6a1a libglib-2.0.so.0`g_main_context_dispatch at gmain.c:3325"
22: B1 Line exceeds max length (86>80): " frame #11: 0x05ad5a64 bluetoothd`mainloop_run_with_signal at mainloop-notify.c:201"
##############################
Test: CheckBuild - PASS
##############################
Test: MakeCheck - PASS
---
Regards,
Linux Bluetooth
diff --git a/profiles/input/hog-lib.c b/profiles/input/hog-lib.c index 1f132aa4c..711bda73c 100644 --- a/profiles/input/hog-lib.c +++ b/profiles/input/hog-lib.c @@ -1651,12 +1651,19 @@ static void primary_cb(uint8_t status, GSList *services, void *user_data) bool bt_hog_attach(struct bt_hog *hog, void *gatt) { GSList *l; + bt_uuid_t uuid; if (hog->attrib) return false; hog->attrib = g_attrib_ref(gatt); + if (!hog->attr && hog->gatt_db) { + bt_uuid16_create(&uuid, HOG_UUID16); + gatt_db_foreach_service(hog->gatt_db, &uuid, + foreach_hog_service, hog); + } + if (!hog->attr && !hog->primary) { discover_primary(hog, hog->attrib, NULL, primary_cb, hog); return true; @@ -1744,6 +1751,15 @@ void bt_hog_detach(struct bt_hog *hog) bt_hog_detach(instance); } + /* hog->attr doesn't own pointer, so it may be invalid when this hog + * object gets re-attached with bt_hog_attach(). So intentionally mark + * it as invalid and remove all instances so that the instances can be + * re-attached at bt_hog_attach(). + */ + hog->attr = NULL; + g_slist_free_full(hog->instances, hog_free); + hog->instances = NULL; + for (l = hog->reports; l; l = l->next) { struct report *r = l->data;
hog->attr does not own pointer, so it may be invalid when hog object gets re-attached at bt_hog_attach(). To solve this, this patch intentionally clears hog->attr at bt_hog_detach() to mark it as invalid so that it can be repopulated with the valid pointer at bt_hog_attach(). The same applies to all sub-instances. Sample stack trace: * thread #1, stop reason = signal SIGSEGV * frame #0: 0x05ad49f2 bluetoothd`<name omitted> at gatt-db.c:1428 frame #1: 0x05a91922 bluetoothd`bt_hog_attach at hog-lib.c:1694 frame #2: 0x05a9160e bluetoothd`hog_accept at hog.c:212 frame #3: 0x05ab4784 bluetoothd`service_accept at service.c:203 frame #4: 0x05aba1e6 bluetoothd`device_attach_att at device.c:4542 frame #5: 0x05a9c4a2 bluetoothd`connect_cb at gatt-database.c:656 frame #6: 0x05a98e8c bluetoothd`server_cb at btio.c:264 frame #7: 0xec8e6a1a libglib-2.0.so.0`g_main_context_dispatch at gmain.c:3325 frame #8: 0xec8e6c58 libglib-2.0.so.0`g_main_context_iterate at gmain.c:4119 frame #9: 0xec8e6e52 libglib-2.0.so.0`g_main_loop_run at gmain.c:4317 frame #10: 0x05ad582e bluetoothd`mainloop_run at mainloop-glib.c:79 frame #11: 0x05ad5a64 bluetoothd`mainloop_run_with_signal at mainloop-notify.c:201 frame #12: 0x05ac35ac bluetoothd`main at main.c:1103 frame #13: 0xec6ed0a2 libc.so.6`__libc_start_main at libc-start.c:308 --- profiles/input/hog-lib.c | 16 ++++++++++++++++ 1 file changed, 16 insertions(+)