diff options
Diffstat (limited to 'extra/source/tigervnc/patches/xorg-server/CVE-2024-0229.02.patch')
-rw-r--r-- | extra/source/tigervnc/patches/xorg-server/CVE-2024-0229.02.patch | 217 |
1 files changed, 217 insertions, 0 deletions
diff --git a/extra/source/tigervnc/patches/xorg-server/CVE-2024-0229.02.patch b/extra/source/tigervnc/patches/xorg-server/CVE-2024-0229.02.patch new file mode 100644 index 000000000..1704fad67 --- /dev/null +++ b/extra/source/tigervnc/patches/xorg-server/CVE-2024-0229.02.patch @@ -0,0 +1,217 @@ +From 219c54b8a3337456ce5270ded6a67bcde53553d5 Mon Sep 17 00:00:00 2001 +From: Peter Hutterer <peter.hutterer@who-t.net> +Date: Mon, 18 Dec 2023 12:26:20 +1000 +Subject: [PATCH] dix: fix DeviceStateNotify event calculation + +The previous code only made sense if one considers buttons and keys to +be mutually exclusive on a device. That is not necessarily true, causing +a number of issues. + +This function allocates and fills in the number of xEvents we need to +send the device state down the wire. This is split across multiple +32-byte devices including one deviceStateNotify event and optional +deviceKeyStateNotify, deviceButtonStateNotify and (possibly multiple) +deviceValuator events. + +The previous behavior would instead compose a sequence +of [state, buttonstate, state, keystate, valuator...]. This is not +protocol correct, and on top of that made the code extremely convoluted. + +Fix this by streamlining: add both button and key into the deviceStateNotify +and then append the key state and button state, followed by the +valuators. Finally, the deviceValuator events contain up to 6 valuators +per event but we only ever sent through 3 at a time. Let's double that +troughput. + +CVE-2024-0229, ZDI-CAN-22678 + +This vulnerability was discovered by: +Jan-Niklas Sohn working with Trend Micro Zero Day Initiative +--- + dix/enterleave.c | 121 ++++++++++++++++++++--------------------------- + 1 file changed, 52 insertions(+), 69 deletions(-) + +diff --git a/dix/enterleave.c b/dix/enterleave.c +index 17964b00a4..7b7ba1098b 100644 +--- a/dix/enterleave.c ++++ b/dix/enterleave.c +@@ -615,9 +615,15 @@ FixDeviceValuator(DeviceIntPtr dev, deviceValuator * ev, ValuatorClassPtr v, + + ev->type = DeviceValuator; + ev->deviceid = dev->id; +- ev->num_valuators = nval < 3 ? nval : 3; ++ ev->num_valuators = nval < 6 ? nval : 6; + ev->first_valuator = first; + switch (ev->num_valuators) { ++ case 6: ++ ev->valuator2 = v->axisVal[first + 5]; ++ case 5: ++ ev->valuator2 = v->axisVal[first + 4]; ++ case 4: ++ ev->valuator2 = v->axisVal[first + 3]; + case 3: + ev->valuator2 = v->axisVal[first + 2]; + case 2: +@@ -626,7 +632,6 @@ FixDeviceValuator(DeviceIntPtr dev, deviceValuator * ev, ValuatorClassPtr v, + ev->valuator0 = v->axisVal[first]; + break; + } +- first += ev->num_valuators; + } + + static void +@@ -646,7 +651,7 @@ FixDeviceStateNotify(DeviceIntPtr dev, deviceStateNotify * ev, KeyClassPtr k, + ev->num_buttons = b->numButtons; + memcpy((char *) ev->buttons, (char *) b->down, 4); + } +- else if (k) { ++ if (k) { + ev->classes_reported |= (1 << KeyClass); + ev->num_keys = k->xkbInfo->desc->max_key_code - + k->xkbInfo->desc->min_key_code; +@@ -670,15 +675,26 @@ FixDeviceStateNotify(DeviceIntPtr dev, deviceStateNotify * ev, KeyClassPtr k, + } + } + +- ++/** ++ * The device state notify event is split across multiple 32-byte events. ++ * The first one contains the first 32 button state bits, the first 32 ++ * key state bits, and the first 3 valuator values. ++ * ++ * If a device has more than that, the server sends out: ++ * - one deviceButtonStateNotify for buttons 32 and above ++ * - one deviceKeyStateNotify for keys 32 and above ++ * - one deviceValuator event per 6 valuators above valuator 4 ++ * ++ * All events but the last one have the deviceid binary ORed with MORE_EVENTS, ++ */ + static void + DeliverStateNotifyEvent(DeviceIntPtr dev, WindowPtr win) + { ++ /* deviceStateNotify, deviceKeyStateNotify, deviceButtonStateNotify ++ * and one deviceValuator for each 6 valuators */ ++ deviceStateNotify sev[3 + (MAX_VALUATORS + 6)/6]; + int evcount = 1; +- deviceStateNotify sev[6 + (MAX_VALUATORS + 2)/3]; +- deviceStateNotify *ev; +- deviceKeyStateNotify *kev; +- deviceButtonStateNotify *bev; ++ deviceStateNotify *ev = sev; + + KeyClassPtr k; + ButtonClassPtr b; +@@ -691,82 +707,49 @@ DeliverStateNotifyEvent(DeviceIntPtr dev, WindowPtr win) + + if ((b = dev->button) != NULL) { + nbuttons = b->numButtons; +- if (nbuttons > 32) ++ if (nbuttons > 32) /* first 32 are encoded in deviceStateNotify */ + evcount++; + } + if ((k = dev->key) != NULL) { + nkeys = k->xkbInfo->desc->max_key_code - k->xkbInfo->desc->min_key_code; +- if (nkeys > 32) ++ if (nkeys > 32) /* first 32 are encoded in deviceStateNotify */ + evcount++; +- if (nbuttons > 0) { +- evcount++; +- } + } + if ((v = dev->valuator) != NULL) { + nval = v->numAxes; +- +- if (nval > 3) +- evcount++; +- if (nval > 6) { +- if (!(k && b)) +- evcount++; +- if (nval > 9) +- evcount += ((nval - 7) / 3); +- } ++ /* first three are encoded in deviceStateNotify, then ++ * it's 6 per deviceValuator event */ ++ evcount += ((nval - 3) + 6)/6; + } + +- ev = sev; +- FixDeviceStateNotify(dev, ev, NULL, NULL, NULL, first); +- +- if (b != NULL) { +- FixDeviceStateNotify(dev, ev++, NULL, b, v, first); +- first += 3; +- nval -= 3; +- if (nbuttons > 32) { +- (ev - 1)->deviceid |= MORE_EVENTS; +- bev = (deviceButtonStateNotify *) ev++; +- bev->type = DeviceButtonStateNotify; +- bev->deviceid = dev->id; +- memcpy((char *) &bev->buttons[4], (char *) &b->down[4], +- DOWN_LENGTH - 4); +- } +- if (nval > 0) { +- (ev - 1)->deviceid |= MORE_EVENTS; +- FixDeviceValuator(dev, (deviceValuator *) ev++, v, first); +- first += 3; +- nval -= 3; +- } ++ BUG_RETURN(evcount <= ARRAY_SIZE(sev)); ++ ++ FixDeviceStateNotify(dev, ev, k, b, v, first); ++ ++ if (b != NULL && nbuttons > 32) { ++ deviceButtonStateNotify *bev = (deviceButtonStateNotify *) ++ev; ++ (ev - 1)->deviceid |= MORE_EVENTS; ++ bev->type = DeviceButtonStateNotify; ++ bev->deviceid = dev->id; ++ memcpy((char *) &bev->buttons[4], (char *) &b->down[4], ++ DOWN_LENGTH - 4); + } + +- if (k != NULL) { +- FixDeviceStateNotify(dev, ev++, k, NULL, v, first); +- first += 3; +- nval -= 3; +- if (nkeys > 32) { +- (ev - 1)->deviceid |= MORE_EVENTS; +- kev = (deviceKeyStateNotify *) ev++; +- kev->type = DeviceKeyStateNotify; +- kev->deviceid = dev->id; +- memmove((char *) &kev->keys[0], (char *) &k->down[4], 28); +- } +- if (nval > 0) { +- (ev - 1)->deviceid |= MORE_EVENTS; +- FixDeviceValuator(dev, (deviceValuator *) ev++, v, first); +- first += 3; +- nval -= 3; +- } ++ if (k != NULL && nkeys > 32) { ++ deviceKeyStateNotify *kev = (deviceKeyStateNotify *) ++ev; ++ (ev - 1)->deviceid |= MORE_EVENTS; ++ kev->type = DeviceKeyStateNotify; ++ kev->deviceid = dev->id; ++ memmove((char *) &kev->keys[0], (char *) &k->down[4], 28); + } + ++ first = 3; ++ nval -= 3; + while (nval > 0) { +- FixDeviceStateNotify(dev, ev++, NULL, NULL, v, first); +- first += 3; +- nval -= 3; +- if (nval > 0) { +- (ev - 1)->deviceid |= MORE_EVENTS; +- FixDeviceValuator(dev, (deviceValuator *) ev++, v, first); +- first += 3; +- nval -= 3; +- } ++ ev->deviceid |= MORE_EVENTS; ++ FixDeviceValuator(dev, (deviceValuator *) ++ev, v, first); ++ first += 6; ++ nval -= 6; + } + + DeliverEventsToWindow(dev, win, (xEvent *) sev, evcount, +-- +GitLab + |