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CVE-2024-40955

Publication date 12 July 2024

Last updated 13 September 2024

Ubuntu priority

Medium

Why this priority?

Cvss 3 Severity Score

5.5 · Medium

Score breakdown

In the Linux kernel, the following vulnerability has been resolved: ext4: fix slab-out-of-bounds in ext4_mb_find_good_group_avg_frag_lists() We can trigger a slab-out-of-bounds with the following commands: mkfs.ext4 -F /dev/$disk 10G mount /dev/$disk /tmp/test echo 2147483647 > /sys/fs/ext4/$disk/mb_group_prealloc echo test > /tmp/test/file && sync ================================================================== BUG: KASAN: slab-out-of-bounds in ext4_mb_find_good_group_avg_frag_lists+0x8a/0x200 [ext4] Read of size 8 at addr ffff888121b9d0f0 by task kworker/u2:0/11 CPU: 0 PID: 11 Comm: kworker/u2:0 Tainted: GL 6.7.0-next-20240118 #521 Call Trace: dump_stack_lvl+0x2c/0x50 kasan_report+0xb6/0xf0 ext4_mb_find_good_group_avg_frag_lists+0x8a/0x200 [ext4] ext4_mb_regular_allocator+0x19e9/0x2370 [ext4] ext4_mb_new_blocks+0x88a/0x1370 [ext4] ext4_ext_map_blocks+0x14f7/0x2390 [ext4] ext4_map_blocks+0x569/0xea0 [ext4] ext4_do_writepages+0x10f6/0x1bc0 [ext4] [...] ================================================================== The flow of issue triggering is as follows: // Set s_mb_group_prealloc to 2147483647 via sysfs ext4_mb_new_blocks ext4_mb_normalize_request ext4_mb_normalize_group_request ac->ac_g_ex.fe_len = EXT4_SB(sb)->s_mb_group_prealloc ext4_mb_regular_allocator ext4_mb_choose_next_group ext4_mb_choose_next_group_best_avail mb_avg_fragment_size_order order = fls(len) - 2 = 29 ext4_mb_find_good_group_avg_frag_lists frag_list = &sbi->s_mb_avg_fragment_size[order] if (list_empty(frag_list)) // Trigger SOOB! At 4k block size, the length of the s_mb_avg_fragment_size list is 14, but an oversized s_mb_group_prealloc is set, causing slab-out-of-bounds to be triggered by an attempt to access an element at index 29. Add a new attr_id attr_clusters_in_group with values in the range [0, sbi->s_clusters_per_group] and declare mb_group_prealloc as that type to fix the issue. In addition avoid returning an order from mb_avg_fragment_size_order() greater than MB_NUM_ORDERS(sb) and reduce some useless loops.

Status

Package Ubuntu Release Status
linux 24.04 LTS noble
Fixed 6.8.0-44.44
22.04 LTS jammy
Not affected
20.04 LTS focal
Not affected
18.04 LTS bionic
Not affected
16.04 LTS xenial
Not affected
14.04 LTS trusty
Not affected
linux-allwinner-5.19 24.04 LTS noble Not in release
22.04 LTS jammy Ignored
20.04 LTS focal Not in release
linux-aws 24.04 LTS noble
Fixed 6.8.0-1015.16
22.04 LTS jammy
Not affected
20.04 LTS focal
Not affected
18.04 LTS bionic
Not affected
16.04 LTS xenial
Not affected
14.04 LTS trusty
Not affected
linux-aws-5.0 24.04 LTS noble Not in release
22.04 LTS jammy Not in release
20.04 LTS focal Not in release
18.04 LTS bionic Ignored
linux-aws-5.11 24.04 LTS noble Not in release
22.04 LTS jammy Not in release
20.04 LTS focal Ignored
linux-aws-5.13 24.04 LTS noble Not in release
22.04 LTS jammy Not in release
20.04 LTS focal Ignored
linux-aws-5.15 24.04 LTS noble Not in release
22.04 LTS jammy Not in release
20.04 LTS focal
Not affected
linux-aws-5.19 24.04 LTS noble Not in release
22.04 LTS jammy Ignored
20.04 LTS focal Not in release
linux-aws-5.3 24.04 LTS noble Not in release
22.04 LTS jammy Not in release
20.04 LTS focal Not in release
18.04 LTS bionic Ignored
linux-aws-5.4 24.04 LTS noble Not in release
22.04 LTS jammy Not in release
20.04 LTS focal Not in release
18.04 LTS bionic
Not affected
linux-aws-5.8 24.04 LTS noble Not in release
22.04 LTS jammy Not in release
20.04 LTS focal Ignored
linux-aws-6.2 24.04 LTS noble Not in release
22.04 LTS jammy Ignored
20.04 LTS focal Not in release
linux-aws-6.5 24.04 LTS noble Not in release
22.04 LTS jammy Ignored
20.04 LTS focal Not in release
linux-aws-fips 24.04 LTS noble Not in release
22.04 LTS jammy Not in release
20.04 LTS focal Not in release
linux-aws-hwe 24.04 LTS noble Not in release
22.04 LTS jammy Not in release
20.04 LTS focal Not in release
16.04 LTS xenial
Not affected
linux-azure 24.04 LTS noble
Fixed 6.8.0-1014.16
22.04 LTS jammy
Not affected
20.04 LTS focal
Not affected
18.04 LTS bionic Ignored
16.04 LTS xenial
Not affected
14.04 LTS trusty
Not affected
linux-azure-4.15 24.04 LTS noble Not in release
22.04 LTS jammy Not in release
20.04 LTS focal Not in release
18.04 LTS bionic
Not affected
linux-azure-5.11 24.04 LTS noble Not in release
22.04 LTS jammy Not in release
20.04 LTS focal Ignored
linux-azure-5.13 24.04 LTS noble Not in release
22.04 LTS jammy Not in release
20.04 LTS focal Ignored
linux-azure-5.15 24.04 LTS noble Not in release
22.04 LTS jammy Not in release
20.04 LTS focal
Not affected
linux-azure-5.19 24.04 LTS noble Not in release
22.04 LTS jammy Ignored
20.04 LTS focal Not in release
linux-azure-5.3 24.04 LTS noble Not in release
22.04 LTS jammy Not in release
20.04 LTS focal Not in release
18.04 LTS bionic Ignored
linux-azure-5.4 24.04 LTS noble Not in release
22.04 LTS jammy Not in release
20.04 LTS focal Not in release
18.04 LTS bionic
Not affected
linux-azure-5.8 24.04 LTS noble Not in release
22.04 LTS jammy Not in release
20.04 LTS focal Ignored
linux-azure-6.2 24.04 LTS noble Not in release
22.04 LTS jammy Ignored
20.04 LTS focal Not in release
linux-azure-6.5 24.04 LTS noble Not in release
22.04 LTS jammy Ignored
20.04 LTS focal Not in release
linux-azure-edge 24.04 LTS noble Not in release
22.04 LTS jammy Not in release
20.04 LTS focal Not in release
18.04 LTS bionic Ignored
linux-azure-fde 24.04 LTS noble Not in release
22.04 LTS jammy
Not affected
20.04 LTS focal Ignored
linux-azure-fde-5.15 24.04 LTS noble Not in release
22.04 LTS jammy Not in release
20.04 LTS focal
Not affected
linux-azure-fde-5.19 24.04 LTS noble Not in release
22.04 LTS jammy Ignored
20.04 LTS focal Not in release
linux-azure-fde-6.2 24.04 LTS noble Not in release
22.04 LTS jammy Ignored
20.04 LTS focal Not in release
linux-azure-fips 24.04 LTS noble Not in release
22.04 LTS jammy Not in release
20.04 LTS focal Not in release
linux-bluefield 24.04 LTS noble Not in release
22.04 LTS jammy Not in release
20.04 LTS focal
Not affected
linux-fips 24.04 LTS noble Not in release
22.04 LTS jammy Not in release
20.04 LTS focal Not in release
linux-gcp 24.04 LTS noble
Fixed 6.8.0-1014.16
22.04 LTS jammy
Not affected
20.04 LTS focal
Not affected
18.04 LTS bionic Ignored
16.04 LTS xenial
Not affected
linux-gcp-4.15 24.04 LTS noble Not in release
22.04 LTS jammy Not in release
20.04 LTS focal Not in release
18.04 LTS bionic
Not affected
linux-gcp-5.11 24.04 LTS noble Not in release
22.04 LTS jammy Not in release
20.04 LTS focal Ignored
linux-gcp-5.13 24.04 LTS noble Not in release
22.04 LTS jammy Not in release
20.04 LTS focal Ignored
linux-gcp-5.15 24.04 LTS noble Not in release
22.04 LTS jammy Not in release
20.04 LTS focal
Not affected
linux-gcp-5.19 24.04 LTS noble Not in release
22.04 LTS jammy Ignored
20.04 LTS focal Not in release
linux-gcp-5.3 24.04 LTS noble Not in release
22.04 LTS jammy Not in release
20.04 LTS focal Not in release
18.04 LTS bionic Ignored
linux-gcp-5.4 24.04 LTS noble Not in release
22.04 LTS jammy Not in release
20.04 LTS focal Not in release
18.04 LTS bionic
Not affected
linux-gcp-5.8 24.04 LTS noble Not in release
22.04 LTS jammy Not in release
20.04 LTS focal Ignored
linux-gcp-6.2 24.04 LTS noble Not in release
22.04 LTS jammy Ignored
20.04 LTS focal Not in release
linux-gcp-6.5 24.04 LTS noble Not in release
22.04 LTS jammy Ignored
20.04 LTS focal Not in release
linux-gcp-fips 24.04 LTS noble Not in release
22.04 LTS jammy Not in release
20.04 LTS focal Not in release
linux-gke 24.04 LTS noble
Fixed 6.8.0-1010.13
22.04 LTS jammy
Not affected
20.04 LTS focal Ignored
linux-gke-4.15 24.04 LTS noble Not in release
22.04 LTS jammy Not in release
20.04 LTS focal Not in release
18.04 LTS bionic Ignored
linux-gke-5.15 24.04 LTS noble Not in release
22.04 LTS jammy Not in release
20.04 LTS focal Ignored
linux-gke-5.4 24.04 LTS noble Not in release
22.04 LTS jammy Not in release
20.04 LTS focal Not in release
18.04 LTS bionic Ignored
linux-gkeop 24.04 LTS noble Not in release
22.04 LTS jammy
Not affected
20.04 LTS focal
Not affected
linux-gkeop-5.15 24.04 LTS noble Not in release
22.04 LTS jammy Not in release
20.04 LTS focal
Not affected
linux-gkeop-5.4 24.04 LTS noble Not in release
22.04 LTS jammy Not in release
20.04 LTS focal Not in release
18.04 LTS bionic Ignored
linux-hwe 24.04 LTS noble Not in release
22.04 LTS jammy Not in release
20.04 LTS focal Not in release
18.04 LTS bionic Ignored
16.04 LTS xenial
Not affected
linux-hwe-5.11 24.04 LTS noble Not in release
22.04 LTS jammy Not in release
20.04 LTS focal Ignored
linux-hwe-5.13 24.04 LTS noble Not in release
22.04 LTS jammy Not in release
20.04 LTS focal Ignored
linux-hwe-5.15 24.04 LTS noble Not in release
22.04 LTS jammy Not in release
20.04 LTS focal
Not affected
linux-hwe-5.19 24.04 LTS noble Not in release
22.04 LTS jammy Ignored
20.04 LTS focal Not in release
linux-hwe-5.4 24.04 LTS noble Not in release
22.04 LTS jammy Not in release
20.04 LTS focal Not in release
18.04 LTS bionic
Not affected
linux-hwe-5.8 24.04 LTS noble Not in release
22.04 LTS jammy Not in release
20.04 LTS focal Ignored
linux-hwe-6.2 24.04 LTS noble Not in release
22.04 LTS jammy Ignored
20.04 LTS focal Not in release
linux-hwe-6.5 24.04 LTS noble Not in release
22.04 LTS jammy Ignored
20.04 LTS focal Not in release
linux-hwe-6.8 24.04 LTS noble Not in release
22.04 LTS jammy
Vulnerable, work in progress
20.04 LTS focal Not in release
18.04 LTS bionic Not in release
16.04 LTS xenial Not in release
14.04 LTS trusty Not in release
linux-hwe-edge 24.04 LTS noble Not in release
22.04 LTS jammy Not in release
20.04 LTS focal Not in release
18.04 LTS bionic Ignored
16.04 LTS xenial Ignored
linux-ibm 24.04 LTS noble
Fixed 6.8.0-1012.12
22.04 LTS jammy
Not affected
20.04 LTS focal
Not affected
linux-ibm-5.15 24.04 LTS noble Not in release
22.04 LTS jammy Not in release
20.04 LTS focal
Not affected
linux-ibm-5.4 24.04 LTS noble Not in release
22.04 LTS jammy Not in release
20.04 LTS focal Not in release
18.04 LTS bionic
Not affected
linux-intel 24.04 LTS noble
Not affected
22.04 LTS jammy Not in release
20.04 LTS focal Not in release
linux-intel-5.13 24.04 LTS noble Not in release
22.04 LTS jammy Not in release
20.04 LTS focal Ignored
linux-intel-iot-realtime 24.04 LTS noble Not in release
22.04 LTS jammy Not in release
20.04 LTS focal Not in release
18.04 LTS bionic Not in release
16.04 LTS xenial Not in release
14.04 LTS trusty Not in release
linux-intel-iotg 24.04 LTS noble Not in release
22.04 LTS jammy
Not affected
20.04 LTS focal Not in release
linux-intel-iotg-5.15 24.04 LTS noble Not in release
22.04 LTS jammy Not in release
20.04 LTS focal
Not affected
linux-iot 24.04 LTS noble Not in release
22.04 LTS jammy Not in release
20.04 LTS focal
Not affected
linux-kvm 24.04 LTS noble Not in release
22.04 LTS jammy
Not affected
20.04 LTS focal
Not affected
18.04 LTS bionic
Not affected
16.04 LTS xenial
Not affected
linux-laptop 24.04 LTS noble Not in release
22.04 LTS jammy Not in release
20.04 LTS focal Not in release
18.04 LTS bionic Not in release
16.04 LTS xenial Not in release
14.04 LTS trusty Not in release
linux-lowlatency 24.04 LTS noble
Fixed 6.8.0-44.44.1
22.04 LTS jammy
Not affected
20.04 LTS focal Not in release
linux-lowlatency-hwe-5.15 24.04 LTS noble Not in release
22.04 LTS jammy Not in release
20.04 LTS focal
Not affected
linux-lowlatency-hwe-5.19 24.04 LTS noble Not in release
22.04 LTS jammy Ignored
20.04 LTS focal Not in release
linux-lowlatency-hwe-6.2 24.04 LTS noble Not in release
22.04 LTS jammy Ignored
20.04 LTS focal Not in release
linux-lowlatency-hwe-6.5 24.04 LTS noble Not in release
22.04 LTS jammy Ignored
20.04 LTS focal Not in release
linux-lowlatency-hwe-6.8 24.04 LTS noble Not in release
22.04 LTS jammy
Fixed 6.8.0-44.44.1~22.04.1
20.04 LTS focal Not in release
18.04 LTS bionic Not in release
16.04 LTS xenial Not in release
14.04 LTS trusty Not in release
linux-lts-xenial 24.04 LTS noble Not in release
22.04 LTS jammy Not in release
20.04 LTS focal Not in release
14.04 LTS trusty
Not affected
linux-nvidia 24.04 LTS noble
Fixed 6.8.0-1013.14
22.04 LTS jammy
Not affected
20.04 LTS focal Not in release
linux-nvidia-6.2 24.04 LTS noble Not in release
22.04 LTS jammy Ignored
20.04 LTS focal Not in release
linux-nvidia-6.5 24.04 LTS noble Not in release
22.04 LTS jammy
Vulnerable
20.04 LTS focal Not in release
linux-nvidia-6.8 24.04 LTS noble Not in release
22.04 LTS jammy
Fixed 6.8.0-1013.14~22.04.1
20.04 LTS focal Not in release
18.04 LTS bionic Not in release
16.04 LTS xenial Not in release
14.04 LTS trusty Not in release
linux-nvidia-lowlatency 24.04 LTS noble
Fixed 6.8.0-1013.14.1
22.04 LTS jammy Not in release
20.04 LTS focal Not in release
18.04 LTS bionic Not in release
16.04 LTS xenial Not in release
14.04 LTS trusty Not in release
linux-oem 24.04 LTS noble Not in release
22.04 LTS jammy Not in release
20.04 LTS focal Not in release
18.04 LTS bionic Ignored
linux-oem-5.10 24.04 LTS noble Not in release
22.04 LTS jammy Not in release
20.04 LTS focal Ignored
linux-oem-5.13 24.04 LTS noble Not in release
22.04 LTS jammy Not in release
20.04 LTS focal Ignored
linux-oem-5.14 24.04 LTS noble Not in release
22.04 LTS jammy Not in release
20.04 LTS focal Ignored
linux-oem-5.17 24.04 LTS noble Not in release
22.04 LTS jammy Ignored
20.04 LTS focal Not in release
linux-oem-5.6 24.04 LTS noble Not in release
22.04 LTS jammy Not in release
20.04 LTS focal Ignored
linux-oem-6.0 24.04 LTS noble Not in release
22.04 LTS jammy Ignored
20.04 LTS focal Not in release
linux-oem-6.1 24.04 LTS noble Not in release
22.04 LTS jammy Ignored
20.04 LTS focal Not in release
linux-oem-6.5 24.04 LTS noble Not in release
22.04 LTS jammy Ignored
20.04 LTS focal Not in release
linux-oem-6.8 24.04 LTS noble
Fixed 6.8.0-1012.12
22.04 LTS jammy Not in release
20.04 LTS focal Not in release
linux-oracle 24.04 LTS noble
Fixed 6.8.0-1012.12
22.04 LTS jammy
Not affected
20.04 LTS focal
Not affected
18.04 LTS bionic
Not affected
16.04 LTS xenial
Not affected
linux-oracle-5.0 24.04 LTS noble Not in release
22.04 LTS jammy Not in release
20.04 LTS focal Not in release
18.04 LTS bionic Ignored
linux-oracle-5.11 24.04 LTS noble Not in release
22.04 LTS jammy Not in release
20.04 LTS focal Ignored
linux-oracle-5.13 24.04 LTS noble Not in release
22.04 LTS jammy Not in release
20.04 LTS focal Ignored
linux-oracle-5.15 24.04 LTS noble Not in release
22.04 LTS jammy Not in release
20.04 LTS focal
Not affected
linux-oracle-5.3 24.04 LTS noble Not in release
22.04 LTS jammy Not in release
20.04 LTS focal Not in release
18.04 LTS bionic Ignored
linux-oracle-5.4 24.04 LTS noble Not in release
22.04 LTS jammy Not in release
20.04 LTS focal Not in release
18.04 LTS bionic
Not affected
linux-oracle-5.8 24.04 LTS noble Not in release
22.04 LTS jammy Not in release
20.04 LTS focal Ignored
linux-oracle-6.5 24.04 LTS noble Not in release
22.04 LTS jammy Ignored
20.04 LTS focal Not in release
linux-raspi 24.04 LTS noble
Vulnerable, work in progress
22.04 LTS jammy
Not affected
20.04 LTS focal
Not affected
linux-raspi-5.4 24.04 LTS noble Not in release
22.04 LTS jammy Not in release
20.04 LTS focal Not in release
18.04 LTS bionic
Not affected
linux-raspi-realtime 24.04 LTS noble Not in release
22.04 LTS jammy Not in release
20.04 LTS focal Not in release
18.04 LTS bionic Not in release
16.04 LTS xenial Not in release
14.04 LTS trusty Not in release
linux-raspi2 24.04 LTS noble Not in release
22.04 LTS jammy Not in release
20.04 LTS focal Ignored
linux-realtime 24.04 LTS noble Not in release
22.04 LTS jammy Ignored
20.04 LTS focal Not in release
18.04 LTS bionic Not in release
16.04 LTS xenial Not in release
14.04 LTS trusty Not in release
linux-riscv 24.04 LTS noble
Fixed 6.8.0-44.44.1
22.04 LTS jammy Ignored
20.04 LTS focal Ignored
linux-riscv-5.11 24.04 LTS noble Not in release
22.04 LTS jammy Not in release
20.04 LTS focal Ignored
linux-riscv-5.15 24.04 LTS noble Not in release
22.04 LTS jammy Not in release
20.04 LTS focal
Not affected
linux-riscv-5.19 24.04 LTS noble Not in release
22.04 LTS jammy Ignored
20.04 LTS focal Not in release
linux-riscv-5.8 24.04 LTS noble Not in release
22.04 LTS jammy Not in release
20.04 LTS focal Ignored
linux-riscv-6.5 24.04 LTS noble Not in release
22.04 LTS jammy Ignored
20.04 LTS focal Not in release
linux-riscv-6.8 24.04 LTS noble Not in release
22.04 LTS jammy
Fixed 6.8.0-44.44.1~22.04.1
20.04 LTS focal Not in release
18.04 LTS bionic Not in release
16.04 LTS xenial Not in release
14.04 LTS trusty Not in release
linux-starfive 24.04 LTS noble Not in release
22.04 LTS jammy Not in release
20.04 LTS focal Not in release
18.04 LTS bionic Not in release
16.04 LTS xenial Not in release
14.04 LTS trusty Not in release
linux-starfive-5.19 24.04 LTS noble Not in release
22.04 LTS jammy Ignored
20.04 LTS focal Not in release
linux-starfive-6.2 24.04 LTS noble Not in release
22.04 LTS jammy Ignored
20.04 LTS focal Not in release
linux-starfive-6.5 24.04 LTS noble Not in release
22.04 LTS jammy Ignored
20.04 LTS focal Not in release
linux-xilinx-zynqmp 24.04 LTS noble Not in release
22.04 LTS jammy
Not affected
20.04 LTS focal
Not affected

Patch details

For informational purposes only. We recommend not to cherry-pick updates. How can I get the fixes?

Package Patch details
linux

Severity score breakdown

Parameter Value
Base score 5.5 · Medium
Attack vector Local
Attack complexity Low
Privileges required Low
User interaction None
Scope Unchanged
Confidentiality None
Integrity impact None
Availability impact High
Vector CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

References

Related Ubuntu Security Notices (USN)

    • USN-6999-1
    • Linux kernel vulnerabilities
    • 11 September 2024
    • USN-7004-1
    • Linux kernel vulnerabilities
    • 12 September 2024
    • USN-7005-1
    • Linux kernel vulnerabilities
    • 12 September 2024
    • USN-7005-2
    • Linux kernel vulnerabilities
    • 13 September 2024
    • USN-7008-1
    • Linux kernel vulnerabilities
    • 13 September 2024

Other references