| From bippy-5f407fcff5a0 Mon Sep 17 00:00:00 2001 |
| From: Greg Kroah-Hartman <gregkh@linuxfoundation.org> |
| To: <linux-cve-announce@vger.kernel.org> |
| Reply-to: <cve@kernel.org>, <linux-kernel@vger.kernel.org> |
| Subject: CVE-2024-26611: xsk: fix usage of multi-buffer BPF helpers for ZC XDP |
| |
| Description |
| =========== |
| |
| In the Linux kernel, the following vulnerability has been resolved: |
| |
| xsk: fix usage of multi-buffer BPF helpers for ZC XDP |
| |
| Currently when packet is shrunk via bpf_xdp_adjust_tail() and memory |
| type is set to MEM_TYPE_XSK_BUFF_POOL, null ptr dereference happens: |
| |
| [1136314.192256] BUG: kernel NULL pointer dereference, address: |
| 0000000000000034 |
| [1136314.203943] #PF: supervisor read access in kernel mode |
| [1136314.213768] #PF: error_code(0x0000) - not-present page |
| [1136314.223550] PGD 0 P4D 0 |
| [1136314.230684] Oops: 0000 [#1] PREEMPT SMP NOPTI |
| [1136314.239621] CPU: 8 PID: 54203 Comm: xdpsock Not tainted 6.6.0+ #257 |
| [1136314.250469] Hardware name: Intel Corporation S2600WFT/S2600WFT, |
| BIOS SE5C620.86B.02.01.0008.031920191559 03/19/2019 |
| [1136314.265615] RIP: 0010:__xdp_return+0x6c/0x210 |
| [1136314.274653] Code: ad 00 48 8b 47 08 49 89 f8 a8 01 0f 85 9b 01 00 00 0f 1f 44 00 00 f0 41 ff 48 34 75 32 4c 89 c7 e9 79 cd 80 ff 83 fe 03 75 17 <f6> 41 34 01 0f 85 02 01 00 00 48 89 cf e9 22 cc 1e 00 e9 3d d2 86 |
| [1136314.302907] RSP: 0018:ffffc900089f8db0 EFLAGS: 00010246 |
| [1136314.312967] RAX: ffffc9003168aed0 RBX: ffff8881c3300000 RCX: |
| 0000000000000000 |
| [1136314.324953] RDX: 0000000000000000 RSI: 0000000000000003 RDI: |
| ffffc9003168c000 |
| [1136314.336929] RBP: 0000000000000ae0 R08: 0000000000000002 R09: |
| 0000000000010000 |
| [1136314.348844] R10: ffffc9000e495000 R11: 0000000000000040 R12: |
| 0000000000000001 |
| [1136314.360706] R13: 0000000000000524 R14: ffffc9003168aec0 R15: |
| 0000000000000001 |
| [1136314.373298] FS: 00007f8df8bbcb80(0000) GS:ffff8897e0e00000(0000) |
| knlGS:0000000000000000 |
| [1136314.386105] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 |
| [1136314.396532] CR2: 0000000000000034 CR3: 00000001aa912002 CR4: |
| 00000000007706f0 |
| [1136314.408377] DR0: 0000000000000000 DR1: 0000000000000000 DR2: |
| 0000000000000000 |
| [1136314.420173] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: |
| 0000000000000400 |
| [1136314.431890] PKRU: 55555554 |
| [1136314.439143] Call Trace: |
| [1136314.446058] <IRQ> |
| [1136314.452465] ? __die+0x20/0x70 |
| [1136314.459881] ? page_fault_oops+0x15b/0x440 |
| [1136314.468305] ? exc_page_fault+0x6a/0x150 |
| [1136314.476491] ? asm_exc_page_fault+0x22/0x30 |
| [1136314.484927] ? __xdp_return+0x6c/0x210 |
| [1136314.492863] bpf_xdp_adjust_tail+0x155/0x1d0 |
| [1136314.501269] bpf_prog_ccc47ae29d3b6570_xdp_sock_prog+0x15/0x60 |
| [1136314.511263] ice_clean_rx_irq_zc+0x206/0xc60 [ice] |
| [1136314.520222] ? ice_xmit_zc+0x6e/0x150 [ice] |
| [1136314.528506] ice_napi_poll+0x467/0x670 [ice] |
| [1136314.536858] ? ttwu_do_activate.constprop.0+0x8f/0x1a0 |
| [1136314.546010] __napi_poll+0x29/0x1b0 |
| [1136314.553462] net_rx_action+0x133/0x270 |
| [1136314.561619] __do_softirq+0xbe/0x28e |
| [1136314.569303] do_softirq+0x3f/0x60 |
| |
| This comes from __xdp_return() call with xdp_buff argument passed as |
| NULL which is supposed to be consumed by xsk_buff_free() call. |
| |
| To address this properly, in ZC case, a node that represents the frag |
| being removed has to be pulled out of xskb_list. Introduce |
| appropriate xsk helpers to do such node operation and use them |
| accordingly within bpf_xdp_adjust_tail(). |
| |
| The Linux kernel CVE team has assigned CVE-2024-26611 to this issue. |
| |
| |
| Affected and fixed versions |
| =========================== |
| |
| Issue introduced in 6.6 with commit 24ea50127ecf0efe819c1f6230add27abc6ca9d9 and fixed in 6.6.15 with commit 82ee4781b8200e44669a354140d5c6bd966b8768 |
| Issue introduced in 6.6 with commit 24ea50127ecf0efe819c1f6230add27abc6ca9d9 and fixed in 6.7.3 with commit 5cd781f7216f980207af09c5e0e1bb1eda284540 |
| Issue introduced in 6.6 with commit 24ea50127ecf0efe819c1f6230add27abc6ca9d9 and fixed in 6.8 with commit c5114710c8ce86b8317e9b448f4fd15c711c2a82 |
| |
| Please see https://www.kernel.org for a full list of currently supported |
| kernel versions by the kernel community. |
| |
| Unaffected versions might change over time as fixes are backported to |
| older supported kernel versions. The official CVE entry at |
| https://cve.org/CVERecord/?id=CVE-2024-26611 |
| will be updated if fixes are backported, please check that for the most |
| up to date information about this issue. |
| |
| |
| Affected files |
| ============== |
| |
| The file(s) affected by this issue are: |
| include/net/xdp_sock_drv.h |
| net/core/filter.c |
| |
| |
| Mitigation |
| ========== |
| |
| The Linux kernel CVE team recommends that you update to the latest |
| stable kernel version for this, and many other bugfixes. Individual |
| changes are never tested alone, but rather are part of a larger kernel |
| release. Cherry-picking individual commits is not recommended or |
| supported by the Linux kernel community at all. If however, updating to |
| the latest release is impossible, the individual changes to resolve this |
| issue can be found at these commits: |
| https://git.kernel.org/stable/c/82ee4781b8200e44669a354140d5c6bd966b8768 |
| https://git.kernel.org/stable/c/5cd781f7216f980207af09c5e0e1bb1eda284540 |
| https://git.kernel.org/stable/c/c5114710c8ce86b8317e9b448f4fd15c711c2a82 |
