UBUNTU-CVE-2024-50265: Null Pointer Dereference
In the Linux kernel, the following vulnerability has been resolved: ocfs2: remove entry once instead of null-ptr-dereference in ocfs2xaremove() Syzkaller is able to provoke null-ptr-dereference in ocfs2xaremove(): [ 57.319872] (a.out,1161,7):ocfs2xaremove:2028 ERROR: status = -12 [ 57.320420] (a.out,1161,7):ocfs2xacleanupvaluetruncate:1999 ERROR: Partial truncate while removing xattr overlay.upper. Leaking 1 clusters and removing the entry [ 57.321727] BUG: kernel NULL pointer dereference, address: 0000000000000004 [...] [ 57.325727] RIP: 0010:ocfs2xablockwipenamevalue+0x2a/0xc0 [...] [ 57.331328] Call Trace: [ 57.331477] <TASK> [...] [ 57.333511] ? douseraddrfault+0x3e5/0x740 [ 57.333778] ? excpagefault+0x70/0x170 [ 57.334016] ? asmexcpagefault+0x2b/0x30 [ 57.334263] ? pfxocfs2xablockwipenamevalue+0x10/0x10 [ 57.334596] ? ocfs2xablockwipenamevalue+0x2a/0xc0 [ 57.334913] ocfs2xaremoveentry+0x23/0xc0 [ 57.335164] ocfs2xaset+0x704/0xcf0 [ 57.335381] ? rawspinunlock+0x1a/0x40 [ 57.335620] ? ocfs2inodecacheunlock+0x16/0x20 [ 57.335915] ? tracepreempton+0x1e/0x70 [ 57.336153] ? startthishandle+0x16c/0x500 [ 57.336410] ? preemptcountsub+0x50/0x80 [ 57.336656] ? rawreadunlock+0x20/0x40 [ 57.336906] ? startthishandle+0x16c/0x500 [ 57.337162] ocfs2xattrblockset+0xa6/0x1e0 [ 57.337424] ocfs2xattrsethandle+0x1fd/0x5d0 [ 57.337706] ? ocfs2starttrans+0x13d/0x290 [ 57.337971] ocfs2xattrset+0xb13/0xfb0 [ 57.338207] ? dput+0x46/0x1c0 [ 57.338393] ocfs2xattrtrustedset+0x28/0x30 [ 57.338665] ? ocfs2xattrtrustedset+0x28/0x30 [ 57.338948] vfsremovexattr+0x92/0xc0 [ 57.339182] vfsremovexattrlocked+0xd5/0x190 [ 57.339456] ? preemptcountsub+0x50/0x80 [ 57.339705] vfsremovexattr+0x5f/0x100 [...] Reproducer uses faultinject facility to fail ocfs2xaremove() -> ocfs2xavaluetruncate() with -ENOMEM. In this case the comment mentions that we can return 0 if ocfs2xacleanupvaluetruncate() is going to wipe the entry anyway. But the following 'rc' check is wrong and execution flow do 'ocfs2xaremoveentry(loc);' twice: 1st: in ocfs2xacleanupvaluetruncate(); 2nd: returning back to ocfs2xaremove() instead of going to 'out'. Fix this by skipping the 2nd removal of the same entry and making syzkaller repro happy.
Affected Software
Remediation
Recommended actions to resolve this vulnerability, in priority order.
- Upgrade
Upgrade
ubuntu/linux-awsto a version that resolves this vulnerability.Fixed in 4.4.0-1142.148 - Upgrade
Upgrade
ubuntu/linux-azureto a version that resolves this vulnerability.Fixed in 4.15.0-1187.202~14.04.1 - Upgrade
Upgrade
ubuntu/linux-lts-xenialto a version that resolves this vulnerability.Fixed in 4.4.0-267.301~14.04.1 - Upgrade
Upgrade
ubuntu/linuxto a version that resolves this vulnerability.Fixed in 4.4.0-267.301 - Upgrade
Upgrade
ubuntu/linux-awsto a version that resolves this vulnerability.Fixed in 4.4.0-1180.195 - Upgrade
Upgrade
ubuntu/linux-aws-hweto a version that resolves this vulnerability.Fixed in 4.15.0-1179.192~16.04.1 - Upgrade
Upgrade
ubuntu/linux-azureto a version that resolves this vulnerability.Fixed in 4.15.0-1187.202~16.04.1 - Upgrade
Upgrade
ubuntu/linux-gcpto a version that resolves this vulnerability.Fixed in 4.15.0-1172.189~16.04.1 - Upgrade
Upgrade
ubuntu/linux-hweto a version that resolves this vulnerability.Fixed in 4.15.0-236.248~16.04.1 - Upgrade
Upgrade
ubuntu/linux-kvmto a version that resolves this vulnerability.Fixed in 4.4.0-1143.154 - Upgrade
Upgrade
ubuntu/linux-oracleto a version that resolves this vulnerability.Fixed in 4.15.0-1141.152~16.04.1 - Upgrade
Upgrade
ubuntu/linux-fipsto a version that resolves this vulnerability.Fixed in 4.4.0-1112.119 - Upgrade
Upgrade
ubuntu/linuxto a version that resolves this vulnerability.Fixed in 4.15.0-236.248 - Upgrade
Upgrade
ubuntu/linux-awsto a version that resolves this vulnerability.Fixed in 4.15.0-1179.192 - Upgrade
Upgrade
ubuntu/linux-aws-5.4to a version that resolves this vulnerability.Fixed in 5.4.0-1142.152~18.04.1 - Upgrade
Upgrade
ubuntu/linux-azure-4.15to a version that resolves this vulnerability.Fixed in 4.15.0-1187.202 - Upgrade
Upgrade
ubuntu/linux-azure-5.4to a version that resolves this vulnerability.Fixed in 5.4.0-1145.152~18.04.1 - Upgrade
Upgrade
ubuntu/linux-gcp-4.15to a version that resolves this vulnerability.Fixed in 4.15.0-1172.189 - Upgrade
Upgrade
ubuntu/linux-gcp-5.4to a version that resolves this vulnerability.Fixed in 5.4.0-1143.152~18.04.1 - Upgrade
Upgrade
ubuntu/linux-hwe-5.4to a version that resolves this vulnerability.Fixed in 5.4.0-208.228~18.04.1 - Upgrade
Upgrade
ubuntu/linux-ibm-5.4to a version that resolves this vulnerability.Fixed in 5.4.0-1086.91~18.04.1 - Upgrade
Upgrade
ubuntu/linux-kvmto a version that resolves this vulnerability.Fixed in 4.15.0-1162.167 - Upgrade
Upgrade
ubuntu/linux-oracleto a version that resolves this vulnerability.Fixed in 4.15.0-1141.152 - Upgrade
Upgrade
ubuntu/linux-oracle-5.4to a version that resolves this vulnerability.Fixed in 5.4.0-1138.147~18.04.1 - Upgrade
Upgrade
ubuntu/linux-raspi-5.4to a version that resolves this vulnerability.Fixed in 5.4.0-1129.142~18.04.1 - Upgrade
Upgrade
ubuntu/linux-aws-fipsto a version that resolves this vulnerability.Fixed in 4.15.0-2117.123 - Upgrade
Upgrade
ubuntu/linux-azure-fipsto a version that resolves this vulnerability.Fixed in 4.15.0-2096.102 - Upgrade
Upgrade
ubuntu/linux-fipsto a version that resolves this vulnerability.Fixed in 4.15.0-1134.145 - Upgrade
Upgrade
ubuntu/linux-gcp-fipsto a version that resolves this vulnerability.Fixed in 4.15.0-2080.86 - Upgrade
Upgrade
ubuntu/linuxto a version that resolves this vulnerability.Fixed in 5.4.0-208.228 - Upgrade
Upgrade
ubuntu/linux-awsto a version that resolves this vulnerability.Fixed in 5.4.0-1140.150 - Upgrade
Upgrade
ubuntu/linux-aws-5.15to a version that resolves this vulnerability.Fixed in 5.15.0-1080.87~20.04.1 - Upgrade
Upgrade
ubuntu/linux-azureto a version that resolves this vulnerability.Fixed in 5.4.0-1145.152 - Upgrade
Upgrade
ubuntu/linux-azure-5.15to a version that resolves this vulnerability.Fixed in 5.15.0-1081.90~20.04.1 - Upgrade
Upgrade
ubuntu/linux-bluefieldto a version that resolves this vulnerability.Fixed in 5.4.0-1099.106 - Upgrade
Upgrade
ubuntu/linux-gcpto a version that resolves this vulnerability.Fixed in 5.4.0-1143.152 - Upgrade
Upgrade
ubuntu/linux-gcp-5.15to a version that resolves this vulnerability.Fixed in 5.15.0-1077.86~20.04.1 - Upgrade
Upgrade
ubuntu/linux-hwe-5.15to a version that resolves this vulnerability.Fixed in 5.15.0-134.145~20.04.1 - Upgrade
Upgrade
ubuntu/linux-ibmto a version that resolves this vulnerability.Fixed in 5.4.0-1086.91 - Upgrade
Upgrade
ubuntu/linux-ibm-5.15to a version that resolves this vulnerability.Fixed in 5.15.0-1074.77~20.04.1 - Upgrade
Upgrade
ubuntu/linux-intel-iotg-5.15to a version that resolves this vulnerability.Fixed in 5.15.0-1073.79~20.04.2 - Upgrade
Upgrade
ubuntu/linux-iotto a version that resolves this vulnerability.Fixed in 5.4.0-1048.51 - Upgrade
Upgrade
ubuntu/linux-kvmto a version that resolves this vulnerability.Fixed in 5.4.0-1127.136 - Upgrade
Upgrade
ubuntu/linux-lowlatency-hwe-5.15to a version that resolves this vulnerability.Fixed in 5.15.0-133.143~20.04.1 - Upgrade
Upgrade
ubuntu/linux-oracleto a version that resolves this vulnerability.Fixed in 5.4.0-1138.147 - Upgrade
Upgrade
ubuntu/linux-oracle-5.15to a version that resolves this vulnerability.Fixed in 5.15.0-1075.81~20.04.1 - Upgrade
Upgrade
ubuntu/linux-raspito a version that resolves this vulnerability.Fixed in 5.4.0-1129.142 - Upgrade
Upgrade
ubuntu/linux-riscv-5.15to a version that resolves this vulnerability.Fixed in 5.15.0-1073.77~20.04.1 - Upgrade
Upgrade
ubuntu/linux-xilinx-zynqmpto a version that resolves this vulnerability.Fixed in 5.4.0-1058.62 - Upgrade
Upgrade
ubuntu/linux-nvidia-tegra-5.15to a version that resolves this vulnerability.Fixed in 5.15.0-1039.39~20.04.1 - Upgrade
Upgrade
ubuntu/linux-aws-fipsto a version that resolves this vulnerability.Fixed in 5.4.0-1140.151+fips1 - Upgrade
Upgrade
ubuntu/linux-azure-fipsto a version that resolves this vulnerability.Fixed in 5.4.0-1145.152+fips1 - Upgrade
Upgrade
ubuntu/linux-fipsto a version that resolves this vulnerability.Fixed in 5.4.0-1116.126 - Upgrade
Upgrade
ubuntu/linux-gcp-fipsto a version that resolves this vulnerability.Fixed in 5.4.0-1143.152+fips1 - Upgrade
Upgrade
ubuntu/linuxto a version that resolves this vulnerability.Fixed in 5.15.0-133.144 - Upgrade
Upgrade
ubuntu/linux-awsto a version that resolves this vulnerability.Fixed in 5.15.0-1078.85 - Upgrade
Upgrade
ubuntu/linux-aws-6.8to a version that resolves this vulnerability.Fixed in 6.8.0-1027.29~22.04.1 - Upgrade
Upgrade
ubuntu/linux-azureto a version that resolves this vulnerability.Fixed in 5.15.0-1081.90 - Upgrade
Upgrade
ubuntu/linux-azure-6.8to a version that resolves this vulnerability.Fixed in 6.8.0-1027.32~22.04.1 - Upgrade
Upgrade
ubuntu/linux-azure-fdeto a version that resolves this vulnerability.Fixed in 5.15.0-1081.90.1 - Upgrade
Upgrade
ubuntu/linux-gcpto a version that resolves this vulnerability.Fixed in 5.15.0-1077.86 - Upgrade
Upgrade
ubuntu/linux-gcp-6.8to a version that resolves this vulnerability.Fixed in 6.8.0-1028.30~22.04.1 - Upgrade
Upgrade
ubuntu/linux-gketo a version that resolves this vulnerability.Fixed in 5.15.0-1075.81 - Upgrade
Upgrade
ubuntu/linux-gkeopto a version that resolves this vulnerability.Fixed in 5.15.0-1060.68 - Upgrade
Upgrade
ubuntu/linux-hwe-6.8to a version that resolves this vulnerability.Fixed in 6.8.0-58.60~22.04.1 - Upgrade
Upgrade
ubuntu/linux-ibmto a version that resolves this vulnerability.Fixed in 5.15.0-1070.73 - Upgrade
Upgrade
ubuntu/linux-ibm-6.8to a version that resolves this vulnerability.Fixed in 6.8.0-1024.24~22.04.1 - Upgrade
Upgrade
ubuntu/linux-intel-iotgto a version that resolves this vulnerability.Fixed in 5.15.0-1073.79 - Upgrade
Upgrade
ubuntu/linux-kvmto a version that resolves this vulnerability.Fixed in 5.15.0-1076.81 - Upgrade
Upgrade
ubuntu/linux-lowlatencyto a version that resolves this vulnerability.Fixed in 5.15.0-133.143 - Upgrade
Upgrade
ubuntu/linux-lowlatency-hwe-6.8to a version that resolves this vulnerability.Fixed in 6.8.0-58.60.1~22.04.1 - Upgrade
Upgrade
ubuntu/linux-nvidiato a version that resolves this vulnerability.Fixed in 5.15.0-1072.73 - Upgrade
Upgrade
ubuntu/linux-nvidia-6.8to a version that resolves this vulnerability.Fixed in 6.8.0-1026.29~22.04.1 - Upgrade
Upgrade
ubuntu/linux-nvidia-tegrato a version that resolves this vulnerability.Fixed in 5.15.0-1033.33 - Upgrade
Upgrade
ubuntu/linux-nvidia-tegra-igxto a version that resolves this vulnerability.Fixed in 5.15.0-1021.21 - Upgrade
Upgrade
ubuntu/linux-oracleto a version that resolves this vulnerability.Fixed in 5.15.0-1075.81 - Upgrade
Upgrade
ubuntu/linux-oracle-6.8to a version that resolves this vulnerability.Fixed in 6.8.0-1024.25~22.04.1 - Upgrade
Upgrade
ubuntu/linux-raspito a version that resolves this vulnerability.Fixed in 5.15.0-1072.75 - Upgrade
Upgrade
ubuntu/linux-riscv-6.8to a version that resolves this vulnerability.Fixed in 6.8.0-58.60.1~22.04.1 - Upgrade
Upgrade
ubuntu/linux-xilinx-zynqmpto a version that resolves this vulnerability.Fixed in 5.15.0-1044.48 - Upgrade
Upgrade
ubuntu/linux-bluefieldto a version that resolves this vulnerability.Fixed in 5.15.0-1060.62 - Upgrade
Upgrade
ubuntu/linux-intel-iot-realtimeto a version that resolves this vulnerability.Fixed in 5.15.0-1071.73 - Upgrade
Upgrade
ubuntu/linux-realtimeto a version that resolves this vulnerability.Fixed in 5.15.0-1078.86 - Upgrade
Upgrade
ubuntu/linux-realtime-6.8to a version that resolves this vulnerability.Fixed in 6.8.1-1020.21~22.04.1 - Upgrade
Upgrade
ubuntu/linux-aws-fipsto a version that resolves this vulnerability.Fixed in 5.15.0-1078.85+fips1 - Upgrade
Upgrade
ubuntu/linux-azure-fipsto a version that resolves this vulnerability.Fixed in 5.15.0-1080.89+fips1 - Upgrade
Upgrade
ubuntu/linux-fipsto a version that resolves this vulnerability.Fixed in 5.15.0-133.144+fips1 - Upgrade
Upgrade
ubuntu/linux-gcp-fipsto a version that resolves this vulnerability.Fixed in 5.15.0-1077.86+fips1 - Upgrade
Upgrade
ubuntu/linuxto a version that resolves this vulnerability.Fixed in 6.8.0-58.60 - Upgrade
Upgrade
ubuntu/linux-awsto a version that resolves this vulnerability.Fixed in 6.8.0-1027.29 - Upgrade
Upgrade
ubuntu/linux-azureto a version that resolves this vulnerability.Fixed in 6.8.0-1027.32 - Upgrade
Upgrade
ubuntu/linux-azure-6.11to a version that resolves this vulnerability.Fixed in 6.11.0-1012.12~24.04.1 - Upgrade
Upgrade
ubuntu/linux-azure-nvidiato a version that resolves this vulnerability.Fixed in 6.8.0-1014.15 - Upgrade
Upgrade
ubuntu/linux-gcpto a version that resolves this vulnerability.Fixed in 6.8.0-1028.30 - Upgrade
Upgrade
ubuntu/linux-gcp-6.11to a version that resolves this vulnerability.Fixed in 6.11.0-1011.11~24.04.1 - Upgrade
Upgrade
ubuntu/linux-gketo a version that resolves this vulnerability.Fixed in 6.8.0-1023.27 - Upgrade
Upgrade
ubuntu/linux-gkeopto a version that resolves this vulnerability.Fixed in 6.8.0-1010.12 - Upgrade
Upgrade
ubuntu/linux-ibmto a version that resolves this vulnerability.Fixed in 6.8.0-1024.24 - Upgrade
Upgrade
ubuntu/linux-lowlatencyto a version that resolves this vulnerability.Fixed in 6.8.0-58.60.1 - Upgrade
Upgrade
ubuntu/linux-nvidiato a version that resolves this vulnerability.Fixed in 6.8.0-1026.29 - Upgrade
Upgrade
ubuntu/linux-nvidia-6.11to a version that resolves this vulnerability.Fixed in 6.11.0-1007.7 - Upgrade
Upgrade
ubuntu/linux-nvidia-lowlatencyto a version that resolves this vulnerability.Fixed in 6.8.0-1026.29.1 - Upgrade
Upgrade
ubuntu/linux-nvidia-tegrato a version that resolves this vulnerability.Fixed in 6.8.0-1008.8 - Upgrade
Upgrade
ubuntu/linux-oem-6.11to a version that resolves this vulnerability.Fixed in 6.11.0-1015.15 - Upgrade
Upgrade
ubuntu/linux-oem-6.8to a version that resolves this vulnerability.Fixed in 6.8.0-1026.26 - Upgrade
Upgrade
ubuntu/linux-oracleto a version that resolves this vulnerability.Fixed in 6.8.0-1024.25 - Upgrade
Upgrade
ubuntu/linux-raspito a version that resolves this vulnerability.Fixed in 6.8.0-1028.32 - Upgrade
Upgrade
ubuntu/linux-riscvto a version that resolves this vulnerability.Fixed in 6.8.0-58.60.1 - Upgrade
Upgrade
ubuntu/linux-xilinxto a version that resolves this vulnerability.Fixed in 6.8.0-1017.18 - Upgrade
Upgrade
ubuntu/linux-raspi-realtimeto a version that resolves this vulnerability.Fixed in 6.8.0-2023.24 - Upgrade
Upgrade
ubuntu/linux-realtimeto a version that resolves this vulnerability.Fixed in 6.8.1-1020.21 - Upgrade
Upgrade
ubuntu/linux-fipsto a version that resolves this vulnerability.Fixed in 6.8.0-78.78+fips1 - Compensating control
In ocfs2_xa_remove(), skip the second ocfs2_xa_remove_entry(loc) call when ocfs2_xa_cleanup_value_truncate() has already removed the entry, and return to the 'out' path instead of removing the same entry again.
Event History
Frequently Asked Questions
Which Ubuntu kernel package families are listed as affected?
The listed software includes ubuntu/linux, ubuntu/linux-fips, ubuntu/linux-aws, ubuntu/linux-azure, ubuntu/linux-aws-fips, ubuntu/linux-azure-fips, ubuntu/linux-gcp, and ubuntu/linux-gcp-fips.
What level of access does an attacker need?
The severity vector indicates local attack access and low privileges are required. User interaction is not required.
What is the primary impact of successful exploitation?
The vector indicates a high impact on availability, with no stated impact on confidentiality or integrity. The reported failure is a kernel NULL pointer dereference in OCFS2 extended-attribute removal handling.
What operation is implicated in the failure?
The issue occurs in OCFS2 while removing an extended-attribute entry, including a reported partial truncate involving the overlay.upper extended attribute. The affected code path includes ocfs2_xa_remove() and ocfs2_xa_block_wipe_namevalue().