nvme-tcp: fix NULL pointer dereferences in nvmet_tcp_build_p…(CVE-2026-22998)

概要

nvme-tcp: fix NULL pointer dereferences in nvmet_tcp_build_pdu_iovec

原文の説明

取得元が公開している説明をそのまま載せています (多くは英語)。

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

nvme-tcp: fix NULL pointer dereferences in nvmet_tcp_build_pdu_iovec

Commit efa56305908b ("nvmet-tcp: Fix a kernel panic when host sends an invalid H2C PDU length")
added ttag bounds checking and data_offset
validation in nvmet_tcp_handle_h2c_data_pdu(), but it did not validate
whether the command's data structures (cmd->req.sg and cmd->iov) have
been properly initialized before processing H2C_DATA PDUs.

The nvmet_tcp_build_pdu_iovec() function dereferences these pointers
without NULL checks. This can be triggered by sending H2C_DATA PDU
immediately after the ICREQ/ICRESP handshake, before
sending a CONNECT command or NVMe write command.

Attack vectors that trigger NULL pointer dereferences:

H2C_DATA PDU sent before CONNECT → both pointers NULL
H2C_DATA PDU for READ command → cmd->req.sg allocated, cmd->iov NULL
H2C_DATA PDU for uninitialized command slot → both pointers NULL

The fix validates both cmd->req.sg and cmd->iov before calling
nvmet_tcp_build_pdu_iovec(). Both checks are required because:

Uninitialized commands: both NULL
READ commands: cmd->req.sg allocated, cmd->iov NULL
WRITE commands: both allocated

出典: OSV.dev (Open Source Vulnerabilities) NVD OSV

影響パッケージ

Linux Kernel

[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"5.10.249"}]},{"type":"ECOSYSTEM","events":[{"introduced":"5.11.0"},{"fixed":"5.15.199"}]},{"type":"ECOSYSTEM","events":[{"introduced":"5.16.0"},{"fixed":"6.1.162"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.2.0"},{"fixed":"6.6.122"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.7.0"},{"fixed":"6.12.67"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.8.0"},{"fixed":"6.18.7"}]}]

ディストリビューション別の修正状況

各ディストリビューションが公開している、この CVE の修正パッケージ

BellSoft Alpaquita BELL-CVE-2026-22998 linux-lts 修正版: 6.1.163-r0
Debian DEBIAN-CVE-2026-22998 linux 修正版: 5.10.249-1
Ubuntu UBUNTU-CVE-2026-22998 linux-hwe-edge

概要

原文の説明

影響パッケージ

ディストリビューション別の修正状況

参照URL