diff options
Diffstat (limited to 'extra/source/tigervnc/patches/xorg-server/CVE-2024-21886.01.patch')
-rw-r--r-- | extra/source/tigervnc/patches/xorg-server/CVE-2024-21886.01.patch | 70 |
1 files changed, 70 insertions, 0 deletions
diff --git a/extra/source/tigervnc/patches/xorg-server/CVE-2024-21886.01.patch b/extra/source/tigervnc/patches/xorg-server/CVE-2024-21886.01.patch new file mode 100644 index 000000000..e58fe8d78 --- /dev/null +++ b/extra/source/tigervnc/patches/xorg-server/CVE-2024-21886.01.patch @@ -0,0 +1,70 @@ +From bc1fdbe46559dd947674375946bbef54dd0ce36b Mon Sep 17 00:00:00 2001 +From: =?UTF-8?q?Jos=C3=A9=20Exp=C3=B3sito?= <jexposit@redhat.com> +Date: Fri, 22 Dec 2023 18:28:31 +0100 +Subject: [PATCH] Xi: do not keep linked list pointer during recursion + +The `DisableDevice()` function is called whenever an enabled device +is disabled and it moves the device from the `inputInfo.devices` linked +list to the `inputInfo.off_devices` linked list. + +However, its link/unlink operation has an issue during the recursive +call to `DisableDevice()` due to the `prev` pointer pointing to a +removed device. + +This issue leads to a length mismatch between the total number of +devices and the number of device in the list, leading to a heap +overflow and, possibly, to local privilege escalation. + +Simplify the code that checked whether the device passed to +`DisableDevice()` was in `inputInfo.devices` or not and find the +previous device after the recursion. + +CVE-2024-21886, ZDI-CAN-22840 + +This vulnerability was discovered by: +Jan-Niklas Sohn working with Trend Micro Zero Day Initiative +--- + dix/devices.c | 15 ++++++++++++--- + 1 file changed, 12 insertions(+), 3 deletions(-) + +diff --git a/dix/devices.c b/dix/devices.c +index dca98c8d1b..389d28a23c 100644 +--- a/dix/devices.c ++++ b/dix/devices.c +@@ -453,14 +453,20 @@ DisableDevice(DeviceIntPtr dev, BOOL sendevent) + { + DeviceIntPtr *prev, other; + BOOL enabled; ++ BOOL dev_in_devices_list = FALSE; + int flags[MAXDEVICES] = { 0 }; + + if (!dev->enabled) + return TRUE; + +- for (prev = &inputInfo.devices; +- *prev && (*prev != dev); prev = &(*prev)->next); +- if (*prev != dev) ++ for (other = inputInfo.devices; other; other = other->next) { ++ if (other == dev) { ++ dev_in_devices_list = TRUE; ++ break; ++ } ++ } ++ ++ if (!dev_in_devices_list) + return FALSE; + + TouchEndPhysicallyActiveTouches(dev); +@@ -511,6 +517,9 @@ DisableDevice(DeviceIntPtr dev, BOOL sendevent) + LeaveWindow(dev); + SetFocusOut(dev); + ++ for (prev = &inputInfo.devices; ++ *prev && (*prev != dev); prev = &(*prev)->next); ++ + *prev = dev->next; + dev->next = inputInfo.off_devices; + inputInfo.off_devices = dev; +-- +GitLab + |