CVE-2024-53209
CriticalCVSS 9.8Exploitation Probability (EPSS)
Low risk13th percentile - higher than 13% of all known CVEs
Summary
In the Linux kernel, the bnxt_en driver has a vulnerability related to incorrect receive ring space parameters when changing MTU with XDP active. Changing MTU after attaching an XDP multi-buffer can lead to inconsistent aggregation ring configuration, resulting in random memory corruption and crashes.
Risk Assessment
The organization may experience sudden system crashes (kernel panic) or data corruption due to improper DMA buffer allocation. The vulnerability could be exploited to destabilize servers with Broadcom network cards using the bnxt_en driver.
Recommendation
It is recommended to immediately update the Linux kernel to a version containing the fix (commit resolving the issue). If updating is not possible, avoid changing MTU on interfaces with active XDP until the patch is applied.
Original NVD description (English source)
In the Linux kernel, the following vulnerability has been resolved: bnxt_en: Fix receive ring space parameters when XDP is active The MTU setting at the time an XDP multi-buffer is attached determines whether the aggregation ring will be used and the rx_skb_func handler. This is done in bnxt_set_rx_skb_mode(). If the MTU is later changed, the aggregation ring setting may need to be changed and it may become out-of-sync with the settings initially done in bnxt_set_rx_skb_mode(). This may result in random memory corruption and crashes as the HW may DMA data larger than the allocated buffer size, such as: BUG: kernel NULL pointer dereference, address: 00000000000003c0 PGD 0 P4D 0 Oops: 0000 [#1] PREEMPT SMP NOPTI CPU: 17 PID: 0 Comm: swapper/17 Kdump: loaded Tainted: G S OE 6.1.0-226bf9805506 #1 Hardware name: Wiwynn Delta Lake PVT BZA.02601.0150/Delta Lake-Class1, BIOS F0E_3A12 08/26/2021 RIP: 0010:bnxt_rx_pkt+0xe97/0x1ae0 [bnxt_en] Code: 8b 95 70 ff ff ff 4c 8b 9d 48 ff ff ff 66 41 89 87 b4 00 00 00 e9 0b f7 ff ff 0f b7 43 0a 49 8b 95 a8 04 00 00 25 ff 0f 00 00 <0f> b7 14 42 48 c1 e2 06 49 03 95 a0 04 00 00 0f b6 42 33f RSP: 0018:ffffa19f40cc0d18 EFLAGS: 00010202 RAX: 00000000000001e0 RBX: ffff8e2c805c6100 RCX: 00000000000007ff RDX: 0000000000000000 RSI: ffff8e2c271ab990 RDI: ffff8e2c84f12380 RBP: ffffa19f40cc0e48 R08: 000000000001000d R09: 974ea2fcddfa4cbf R10: 0000000000000000 R11: ffffa19f40cc0ff8 R12: ffff8e2c94b58980 R13: ffff8e2c952d6600 R14: 0000000000000016 R15: ffff8e2c271ab990 FS: 0000000000000000(0000) GS:ffff8e3b3f840000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00000000000003c0 CR3: 0000000e8580a004 CR4: 00000000007706e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 PKRU: 55555554 Call Trace: <IRQ> __bnxt_poll_work+0x1c2/0x3e0 [bnxt_en] To address the issue, we now call bnxt_set_rx_skb_mode() within bnxt_change_mtu() to properly set the AGG rings configuration and update rx_skb_func based on the new MTU value. Additionally, BNXT_FLAG_NO_AGG_RINGS is cleared at the beginning of bnxt_set_rx_skb_mode() to make sure it gets set or cleared based on the current MTU.

