CVE-2024-49850

Summary

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

bpf: correctly handle malformed BPF_CORE_TYPE_ID_LOCAL relos

In case of malformed relocation record of kind BPF_CORE_TYPE_ID_LOCAL referencing a non-existing BTF type, function bpf_core_calc_relo_insn would cause a null pointer deference.

Fix this by adding a proper check upper in call stack, as malformed relocation records could be passed from user space.

Simplest reproducer is a program:

r0 = 0
exit

With a single relocation record:

.insn_off = 0,          /* patch first instruction */
.type_id = 100500,      /* this type id does not exist */
.access_str_off = 6,    /* offset of string "0" */
.kind = BPF_CORE_TYPE_ID_LOCAL,

See the link for original reproducer or next commit for a test case.

Affected Software

VendorProductVersion RangeStatus
LinuxLinux74753e1462e77349525daf9eb60ea21ed92d3a97 < dc7ce14f00bcd50641f2110b7a32aa6552e0780faffected
LinuxLinux74753e1462e77349525daf9eb60ea21ed92d3a97 < 2288b54b96dcb55bedebcef3572bb8821fc5e708affected
LinuxLinux74753e1462e77349525daf9eb60ea21ed92d3a97 < 584cd3ff792e1edbea20b2a7df55897159b0be3eaffected
LinuxLinux74753e1462e77349525daf9eb60ea21ed92d3a97 < e7e9c5b2dda29067332df2a85b0141a92b41f218affected
LinuxLinux74753e1462e77349525daf9eb60ea21ed92d3a97 < 3d2786d65aaa954ebd3fcc033ada433e10da21c4affected
LinuxLinux5.17affected
LinuxLinux0 < 5.17unaffected
LinuxLinux6.1.113 <= 6.1.*unaffected
LinuxLinux6.6.54 <= 6.6.*unaffected
LinuxLinux6.10.13 <= 6.10.*unaffected
LinuxLinux6.11.2 <= 6.11.*unaffected
LinuxLinux6.12 <= *unaffected

Weaknesses

ADP Enrichment

CISA ADP Vulnrichment

  • SSVC:
  • Exploitation: none
    • Automatable: no
    • Technical Impact: partial

CVE Program Container

Additional References

References