CVE-2024-49850
Published: October 23, 2024Last modified: October 23, 2024
Description
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.
Severity score breakdown
| Parameter | Value |
|---|---|
| Base score | 5.5 |
| 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 |
Status
| Product | Release | Package | Status |
|---|---|---|---|
| Alpaquita Linux | 23 LTS | linux-lts | Fixed (6.1.114-r0) |
| Stream | linux-lts | Fixed (6.6.58-r0) |
References
- https://git.kernel.org/stable/c/2288b54b96dcb55bedebcef3572bb8821fc5e708
- https://git.kernel.org/stable/c/3d2786d65aaa954ebd3fcc033ada433e10da21c4
- https://git.kernel.org/stable/c/584cd3ff792e1edbea20b2a7df55897159b0be3e
- https://git.kernel.org/stable/c/dc7ce14f00bcd50641f2110b7a32aa6552e0780f
- https://git.kernel.org/stable/c/e7e9c5b2dda29067332df2a85b0141a92b41f218