Description (CNA)
In the Linux kernel, the following vulnerability has been resolved: bpf: Fix oob access in cgroup local storage Lonial reported that an out-of-bounds access in cgroup local storage can be crafted via tail calls. Given two programs each utilizing a cgroup local storage with a different value size, and one program doing a tail call into the other. The verifier will validate each of the indivial programs just fine. However, in the runtime context the bpf_cg_run_ctx holds an bpf_prog_array_item which contains the BPF program as well as any cgroup local storage flavor the program uses. Helpers such as bpf_get_local_storage() pick this up from the runtime context: ctx = container_of(current->bpf_ctx, struct bpf_cg_run_ctx, run_ctx); storage = ctx->prog_item->cgroup_storage[stype]; if (stype == BPF_CGROUP_STORAGE_SHARED) ptr = &READ_ONCE(storage->buf)->data[0]; else ptr = this_cpu_ptr(storage->percpu_buf); For the second program which was called from the originally attached one, this means bpf_get_local_storage() will pick up the former program's map, not its own. With mismatching sizes, this can result in an unintended out-of-bounds access. To fix this issue, we need to extend bpf_map_owner with an array of storage_cookie[] to match on i) the exact maps from the original program if the second program was using bpf_get_local_storage(), or ii) allow the tail call combination if the second program was not using any of the cgroup local storage maps.
Affected (CNA)
| Vendor / product | Versions |
|---|---|
| Linux / Linux | affected 7d9c3427894fe70d1347b4820476bf37736d2ff0 before c1c74584b9b4043c52e41fec415226e582d266a3; affected 7d9c3427894fe70d1347b4820476bf37736d2ff0 before 66da7cee78590259b400e51a70622ccd41da7bb2; affected 7d9c3427894fe70d1347b4820476bf37736d2ff0 before 7acfa07c585e3d7a64654d38f0a5c762877d0b9b; affected 7d9c3427894fe70d1347b4820476bf37736d2ff0 before 41688d1fc5d163a6c2c0e95c0419e2cb31a44648; affected 7d9c3427894fe70d1347b4820476bf37736d2ff0 before 19341d5c59e8c7e8528e40f8663e99d67810473c; affected 7d9c3427894fe70d1347b4820476bf37736d2ff0 before abad3d0bad72a52137e0c350c59542d75ae4f513 |
| Linux / Linux | affected 5.9; unaffected 0 before 5.9; unaffected 5.15.192 through 5.15.*; unaffected 6.1.151 through 6.1.*; unaffected 6.6.105 through 6.6.*; unaffected 6.12.46 through 6.12.*; unaffected 6.16.1 through 6.16.*; unaffected 6.17 through * |
CWE
No CWE identifiers supplied.
References
- https://git.kernel.org/stable/c/c1c74584b9b4043c52e41fec415226e582d266a3
- https://git.kernel.org/stable/c/66da7cee78590259b400e51a70622ccd41da7bb2
- https://git.kernel.org/stable/c/7acfa07c585e3d7a64654d38f0a5c762877d0b9b
- https://git.kernel.org/stable/c/41688d1fc5d163a6c2c0e95c0419e2cb31a44648
- https://git.kernel.org/stable/c/19341d5c59e8c7e8528e40f8663e99d67810473c
- https://git.kernel.org/stable/c/abad3d0bad72a52137e0c350c59542d75ae4f513
ADP enrichment
No English description supplied.
No English description supplied.
No English description supplied.
No references supplied.