CVE-2024-58088 (GCVE-0-2024-58088)

Vulnerability from cvelistv5 – Published: 2025-03-12 09:41 – Updated: 2025-10-01 19:36
VLAI?
Title
bpf: Fix deadlock when freeing cgroup storage
Summary
In the Linux kernel, the following vulnerability has been resolved: bpf: Fix deadlock when freeing cgroup storage The following commit bc235cdb423a ("bpf: Prevent deadlock from recursive bpf_task_storage_[get|delete]") first introduced deadlock prevention for fentry/fexit programs attaching on bpf_task_storage helpers. That commit also employed the logic in map free path in its v6 version. Later bpf_cgrp_storage was first introduced in c4bcfb38a95e ("bpf: Implement cgroup storage available to non-cgroup-attached bpf progs") which faces the same issue as bpf_task_storage, instead of its busy counter, NULL was passed to bpf_local_storage_map_free() which opened a window to cause deadlock: <TASK> (acquiring local_storage->lock) _raw_spin_lock_irqsave+0x3d/0x50 bpf_local_storage_update+0xd1/0x460 bpf_cgrp_storage_get+0x109/0x130 bpf_prog_a4d4a370ba857314_cgrp_ptr+0x139/0x170 ? __bpf_prog_enter_recur+0x16/0x80 bpf_trampoline_6442485186+0x43/0xa4 cgroup_storage_ptr+0x9/0x20 (holding local_storage->lock) bpf_selem_unlink_storage_nolock.constprop.0+0x135/0x160 bpf_selem_unlink_storage+0x6f/0x110 bpf_local_storage_map_free+0xa2/0x110 bpf_map_free_deferred+0x5b/0x90 process_one_work+0x17c/0x390 worker_thread+0x251/0x360 kthread+0xd2/0x100 ret_from_fork+0x34/0x50 ret_from_fork_asm+0x1a/0x30 </TASK> Progs: - A: SEC("fentry/cgroup_storage_ptr") - cgid (BPF_MAP_TYPE_HASH) Record the id of the cgroup the current task belonging to in this hash map, using the address of the cgroup as the map key. - cgrpa (BPF_MAP_TYPE_CGRP_STORAGE) If current task is a kworker, lookup the above hash map using function parameter @owner as the key to get its corresponding cgroup id which is then used to get a trusted pointer to the cgroup through bpf_cgroup_from_id(). This trusted pointer can then be passed to bpf_cgrp_storage_get() to finally trigger the deadlock issue. - B: SEC("tp_btf/sys_enter") - cgrpb (BPF_MAP_TYPE_CGRP_STORAGE) The only purpose of this prog is to fill Prog A's hash map by calling bpf_cgrp_storage_get() for as many userspace tasks as possible. Steps to reproduce: - Run A; - while (true) { Run B; Destroy B; } Fix this issue by passing its busy counter to the free procedure so it can be properly incremented before storage/smap locking.
Severity ?
5.5 (Medium)
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
CWE
Assigner
References
Impacted products
Vendor Product Version
Linux Linux Affected: c4bcfb38a95edb1021a53f2d0356a78120ecfbe4 , < 6ecb9fa14eec5f15d97c84c36896871335f6ddfb (git)
Affected: c4bcfb38a95edb1021a53f2d0356a78120ecfbe4 , < fac674d2bd68f3479f27328626b42d1eebd11fef (git)
Affected: c4bcfb38a95edb1021a53f2d0356a78120ecfbe4 , < fcec95b4ab3e7bc6b2f36e5d59f7e24104ea87f7 (git)
Affected: c4bcfb38a95edb1021a53f2d0356a78120ecfbe4 , < c78f4afbd962f43a3989f45f3ca04300252b19b5 (git)
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    Linux Linux Affected: 6.2
Unaffected: 0 , < 6.2 (semver)
Unaffected: 6.6.80 , ≤ 6.6.* (semver)
Unaffected: 6.12.17 , ≤ 6.12.* (semver)
Unaffected: 6.13.5 , ≤ 6.13.* (semver)
Unaffected: 6.14 , ≤ * (original_commit_for_fix)
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That commit also employed the logic in map\\nfree path in its v6 version.\\n\\nLater bpf_cgrp_storage was first introduced in\\nc4bcfb38a95e (\\\"bpf: Implement cgroup storage available to non-cgroup-attached bpf progs\\\")\\nwhich faces the same issue as bpf_task_storage, instead of its busy\\ncounter, NULL was passed to bpf_local_storage_map_free() which opened\\na window to cause deadlock:\\n\\n\\t\u003cTASK\u003e\\n\\t\\t(acquiring local_storage-\u003elock)\\n\\t_raw_spin_lock_irqsave+0x3d/0x50\\n\\tbpf_local_storage_update+0xd1/0x460\\n\\tbpf_cgrp_storage_get+0x109/0x130\\n\\tbpf_prog_a4d4a370ba857314_cgrp_ptr+0x139/0x170\\n\\t? __bpf_prog_enter_recur+0x16/0x80\\n\\tbpf_trampoline_6442485186+0x43/0xa4\\n\\tcgroup_storage_ptr+0x9/0x20\\n\\t\\t(holding local_storage-\u003elock)\\n\\tbpf_selem_unlink_storage_nolock.constprop.0+0x135/0x160\\n\\tbpf_selem_unlink_storage+0x6f/0x110\\n\\tbpf_local_storage_map_free+0xa2/0x110\\n\\tbpf_map_free_deferred+0x5b/0x90\\n\\tprocess_one_work+0x17c/0x390\\n\\tworker_thread+0x251/0x360\\n\\tkthread+0xd2/0x100\\n\\tret_from_fork+0x34/0x50\\n\\tret_from_fork_asm+0x1a/0x30\\n\\t\u003c/TASK\u003e\\n\\nProgs:\\n - A: SEC(\\\"fentry/cgroup_storage_ptr\\\")\\n   - cgid (BPF_MAP_TYPE_HASH)\\n\\tRecord the id of the cgroup the current task belonging\\n\\tto in this hash map, using the address of the cgroup\\n\\tas the map key.\\n   - cgrpa (BPF_MAP_TYPE_CGRP_STORAGE)\\n\\tIf current task is a kworker, lookup the above hash\\n\\tmap using function parameter @owner as the key to get\\n\\tits corresponding cgroup id which is then used to get\\n\\ta trusted pointer to the cgroup through\\n\\tbpf_cgroup_from_id(). 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