Riskcovery

CVE-2022-49649

xen/netback: avoid entering xenvif_rx_next_skb() with an empty rx queue

State
Published
Severity
5.5 Medium
Published
Feb 26, 2025
Updated
May 11, 2026
Reserved
Feb 26, 2025

Read the record on cve.org

Description

In the Linux kernel, the following vulnerability has been resolved:

xen/netback: avoid entering xenvif_rx_next_skb() with an empty rx queue

xenvif_rx_next_skb() is expecting the rx queue not being empty, but in case the loop in xenvif_rx_action() is doing multiple iterations, the availability of another skb in the rx queue is not being checked.

This can lead to crashes:

[40072.537261] BUG: unable to handle kernel NULL pointer dereference at 0000000000000080 [40072.537407] IP: xenvif_rx_skb+0x23/0x590 [xen_netback] [40072.537534] PGD 0 P4D 0 [40072.537644] Oops: 0000 [#1] SMP NOPTI [40072.537749] CPU: 0 PID: 12505 Comm: v1-c40247-q2-gu Not tainted 4.12.14-122.121-default #1 SLE12-SP5 [40072.537867] Hardware name: HP ProLiant DL580 Gen9/ProLiant DL580 Gen9, BIOS U17 11/23/2021 [40072.537999] task: ffff880433b38100 task.stack: ffffc90043d40000 [40072.538112] RIP: e030:xenvif_rx_skb+0x23/0x590 [xen_netback] [40072.538217] RSP: e02b:ffffc90043d43de0 EFLAGS: 00010246 [40072.538319] RAX: 0000000000000000 RBX: ffffc90043cd7cd0 RCX: 00000000000000f7 [40072.538430] RDX: 0000000000000000 RSI: 0000000000000006 RDI: ffffc90043d43df8 [40072.538531] RBP: 000000000000003f R08: 000077ff80000000 R09: 0000000000000008 [40072.538644] R10: 0000000000007ff0 R11: 00000000000008f6 R12: ffffc90043ce2708 [40072.538745] R13: 0000000000000000 R14: ffffc90043d43ed0 R15: ffff88043ea748c0 [40072.538861] FS: 0000000000000000(0000) GS:ffff880484600000(0000) knlGS:0000000000000000 [40072.538988] CS: e033 DS: 0000 ES: 0000 CR0: 0000000080050033 [40072.539088] CR2: 0000000000000080 CR3: 0000000407ac8000 CR4: 0000000000040660 [40072.539211] Call Trace: [40072.539319] xenvif_rx_action+0x71/0x90 [xen_netback] [40072.539429] xenvif_kthread_guest_rx+0x14a/0x29c [xen_netback]

Fix that by stopping the loop in case the rx queue becomes empty.

Scores

CVSSScoreVectorSource
3.15.5 MediumCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:HCISA-ADP

Weaknesses

Affected Products

ProductVersions
LinuxLinux
  • 98f6d57ced73b723551568262019f1d6c8771f20 to before c0fcceb5f3f1ec197c014fe218c2f28108cacd27Affected
  • 98f6d57ced73b723551568262019f1d6c8771f20 to before d5320c6a27aa975aff740f9cb481dcbde48f4348Affected
  • 98f6d57ced73b723551568262019f1d6c8771f20 to before 5a071aefd6414af5a20321ab58a0557b81993687Affected
  • 98f6d57ced73b723551568262019f1d6c8771f20 to before 7425479d20f9e96f7c3ec8e8a93fe0d7478724cbAffected
  • 98f6d57ced73b723551568262019f1d6c8771f20 to before b9c32a6886af79d6e0ad87a7b01800ed079cdd02Affected
  • 98f6d57ced73b723551568262019f1d6c8771f20 to before b99174ac57fe5d8867448c03b23828e63f24cb1cAffected
  • 98f6d57ced73b723551568262019f1d6c8771f20 to before f0b5c819b062df8bf5f2acf4697e3871cb3722daAffected
  • 98f6d57ced73b723551568262019f1d6c8771f20 to before 94e8100678889ab428e68acadf042de723f094b9Affected
LinuxLinux
  • 4.9Affected
  • before 4.9Not affected
  • 4.9.324 through 4.9.*Not affected
  • 4.14.289 through 4.14.*Not affected
  • 4.19.253 through 4.19.*Not affected
  • 5.4.207 through 5.4.*Not affected
  • 5.10.132 through 5.10.*Not affected
  • 5.15.56 through 5.15.*Not affected
  • 5.18.13 through 5.18.*Not affected
  • 5.19 and laterNot affected

References

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