CVE-2024-43837

Technical Description

In the Linux kernel, the following vulnerability has been resolved:

bpf: Fix null pointer dereference in resolve_prog_type() for BPF_PROG_TYPE_EXT

When loading a EXT program without specifying `attr->attach_prog_fd`,

the `prog->aux->dst_prog` will be null. At this time, calling

resolve_prog_type() anywhere will result in a null pointer dereference.

Example stack trace:

[ 8.107863] Unable to handle kernel NULL pointer dereference at virtual address 0000000000000004

[ 8.108262] Mem abort info:

[ 8.108384] ESR = 0x0000000096000004

[ 8.108547] EC = 0x25: DABT (current EL), IL = 32 bits

[ 8.108722] SET = 0, FnV = 0

[ 8.108827] EA = 0, S1PTW = 0

[ 8.108939] FSC = 0x04: level 0 translation fault

[ 8.109102] Data abort info:

[ 8.109203] ISV = 0, ISS = 0x00000004, ISS2 = 0x00000000

[ 8.109399] CM = 0, WnR = 0, TnD = 0, TagAccess = 0

[ 8.109614] GCS = 0, Overlay = 0, DirtyBit = 0, Xs = 0

[ 8.109836] user pgtable: 4k pages, 48-bit VAs, pgdp=

Remediation

Check the references section for vendor advisories and patches from linux. Update linux_kernel to the latest patched version. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.

Affected Products

References