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UBUNTU-CVE-2023-52486

Dashboard / Vulnerabilities / UBUNTU-CVE-2023-52486

UBUNTU-CVE-2023-52486

Published: 11 Mar 2024Last Modified: 9 Sept 2026

Upstream:

Aliases:

Summary:

Details: In the Linux kernel, the following vulnerability has been resolved: drm: Don't unref the same fb many times by mistake due to deadlock handling If we get a deadlock after the fb lookup in drm_mode_page_flip_ioctl() we proceed to unref the fb and then retry the whole thing from the top. But we forget to reset the fb pointer back to NULL, and so if we then get another error during the retry, before the fb lookup, we proceed the unref the same fb again without having gotten another reference. The end result is that the fb will (eventually) end up being freed while it's still in use. Reset fb to NULL once we've unreffed it to avoid doing it again until we've done another fb lookup. This turned out to be pretty easy to hit on a DG2 when doing async flips (and CONFIG_DEBUG_WW_MUTEX_SLOWPATH=y). The first symptom I saw that drm_closefb() simply got stuck in a busy loop while walking the framebuffer list. Fortunately I was able to convince it to oops instead, and from there it was easier to track down the culprit.

Affected packages

Package

Name: linux-azure

Purl: pkg:deb/ubuntu/linux-azure?arch=source&distro=esm-infra-legacy%2Ftrusty

Affected ranges

Type: ECOSYSTEM

Events:

Introduced- 0

Fixed -4.15.0-1184.199~14.04.1

Affected versions

4.15.0-1023.24~14.04.1

4.15.0-1030.31~14.04.1

4.15.0-1031.32~14.04.1

4.15.0-1032.33~14.04.2

4.15.0-1035.36~14.04.2

4.15.0-1036.38~14.04.2

4.15.0-1037.39~14.04.2

4.15.0-1039.41~14.04.2

4.15.0-1040.44~14.04.1

4.15.0-1041.45~14.04.1

4.15.0-1042.46~14.04.1

4.15.0-1045.49~14.04.1

4.15.0-1046.50~14.04.1

4.15.0-1047.51~14.04.1

4.15.0-1049.54~14.04.1

4.15.0-1050.55~14.04.1

4.15.0-1051.56~14.04.1

4.15.0-1052.57~14.04.1

4.15.0-1055.60~14.04.1

4.15.0-1056.61~14.04.1

4.15.0-1057.62~14.04.1

4.15.0-1059.64~14.04.1

4.15.0-1060.65~14.04.1

4.15.0-1061.66~14.04.1

4.15.0-1063.68~14.04.1

4.15.0-1064.69~14.04.1

4.15.0-1066.71~14.04.1

4.15.0-1067.72~14.04.1

4.15.0-1069.74~14.04.1

4.15.0-1071.76~14.04.1

4.15.0-1074.79~14.04.1

4.15.0-1077.82~14.04.1

4.15.0-1082.92~14.04.1

4.15.0-1083.93~14.04.1

4.15.0-1089.99~14.04.1

4.15.0-1091.101~14.04.1

4.15.0-1092.102~14.04.1

4.15.0-1093.103~14.04.1

4.15.0-1095.105~14.04.1

4.15.0-1096.106~14.04.1

4.15.0-1098.109~14.04.1

4.15.0-1100.111~14.04.1

4.15.0-1102.113~14.04.1

4.15.0-1103.114~14.04.1

4.15.0-1106.118~14.04.1

4.15.0-1108.120~14.04.1

4.15.0-1109.121~14.04.1

4.15.0-1110.122~14.04.1

4.15.0-1111.123~14.04.1

4.15.0-1112.124~14.04.1

4.15.0-1113.126~14.04.1

4.15.0-1114.127~14.04.1

4.15.0-1115.128~14.04.1

4.15.0-1118.131~14.04.1

4.15.0-1121.134~14.04.1

4.15.0-1122.135~14.04.1

4.15.0-1123.136~14.04.1

4.15.0-1124.137~14.04.1

4.15.0-1125.138~14.04.1

4.15.0-1126.139~14.04.1

4.15.0-1127.140~14.04.1

4.15.0-1129.142~14.04.1

4.15.0-1130.143~14.04.1

4.15.0-1131.144~14.04.1

4.15.0-1133.146~14.04.1

4.15.0-1134.147~14.04.1

4.15.0-1136.149~14.04.1

4.15.0-1137.150~14.04.1

4.15.0-1138.151~14.04.1

4.15.0-1139.152~14.04.1

4.15.0-1142.156~14.04.1

4.15.0-1145.160~14.04.1

4.15.0-1146.161~14.04.1

4.15.0-1149.164~14.04.1

4.15.0-1150.165~14.04.1

4.15.0-1151.166~14.04.1

4.15.0-1153.168~14.04.1

4.15.0-1157.172~14.04.2

4.15.0-1158.173~14.04.1

4.15.0-1159.174~14.04.1

4.15.0-1162.177~14.04.1

4.15.0-1163.178~14.04.1

4.15.0-1164.179~14.04.1

4.15.0-1165.180~14.04.1

4.15.0-1166.181~14.04.1

4.15.0-1167.182~14.04.1

4.15.0-1168.183~14.04.1

4.15.0-1169.184~14.04.1

4.15.0-1170.185~14.04.1

4.15.0-1171.186~14.04.1

4.15.0-1172.187~14.04.1

4.15.0-1173.188~14.04.1

4.15.0-1174.189~14.04.1

4.15.0-1175.190~14.04.1

4.15.0-1176.191~14.04.1

4.15.0-1177.192~14.04.1

4.15.0-1178.193~14.04.1

4.15.0-1179.194~14.04.1

4.15.0-1180.195~14.04.1

4.15.0-1181.196~14.04.1

4.15.0-1182.197~14.04.1

4.15.0-1183.198~14.04.1

Common Vulnerability Scoring System

Attack Vector

Network

Adjacent

Local

Physical

Privileges Required

None

Low

High

User Interaction

None

Required

Scope

Unchanged

Changed

Confidentiality

None

Low

High

Integrity

None

Low

High

Availability

None

Low

High