wifi: ath9k: avoid uninit memory read in ath9k_htc_rx_msg()

Description

In the Linux kernel, the following vulnerability has been resolved: wifi: ath9k: avoid uninit memory read in ath9k_htc_rx_msg() syzbot is reporting uninit value at ath9k_htc_rx_msg() [1], for ioctl(USB_RAW_IOCTL_EP_WRITE) can call ath9k_hif_usb_rx_stream() with pkt_len = 0 but ath9k_hif_usb_rx_stream() uses __dev_alloc_skb(pkt_len + 32, GFP_ATOMIC) based on an assumption that pkt_len is valid. As a result, ath9k_hif_usb_rx_stream() allocates skb with uninitialized memory and ath9k_htc_rx_msg() is reading from uninitialized memory. Since bytes accessed by ath9k_htc_rx_msg() is not known until ath9k_htc_rx_msg() is called, it would be difficult to check minimal valid pkt_len at "if (pkt_len > 2 * MAX_RX_BUF_SIZE) {" line in ath9k_hif_usb_rx_stream(). We have two choices. One is to workaround by adding __GFP_ZERO so that ath9k_htc_rx_msg() sees 0 if pkt_len is invalid. The other is to let ath9k_htc_rx_msg() validate pkt_len before accessing. This patch chose the latter. Note that I'm not sure threshold condition is correct, for I can't find details on possible packet length used by this protocol.

Scores

No CVSS score yet: neither the CNA, CISA nor NVD has scored this CVE. NVD status: Deferred.

EPSS (exploitation in 30 days)

0.21% · top 88% of all CVEs (6 Nov 2026)

The list uses the assigner's score when there is one, then CISA's, then NVD's: Not scored.

Affected products

• Linux · Linux

  • affected fb9987d0f748c983bb795a86f47522313f701a08 – < f3d2a3b7e290d0bdbddfcee5a6c3d922e2b7e02a
  • affected fb9987d0f748c983bb795a86f47522313f701a08 – < 84242f15f911f34aec9b22f99d1e9bff19723dbe
  • affected fb9987d0f748c983bb795a86f47522313f701a08 – < 2c485f4f2a64258acc5228e78ffb828c68d9e770
  • affected fb9987d0f748c983bb795a86f47522313f701a08 – < 9661724f6206bd606ecf13acada676a9975d230b
  • affected fb9987d0f748c983bb795a86f47522313f701a08 – < b1b4144508adfc585e43856b31baaf9008a3beb4
  • affected fb9987d0f748c983bb795a86f47522313f701a08 – < 0d2649b288b7b9484e3d4380c0d6c4720a17e473
  • affected fb9987d0f748c983bb795a86f47522313f701a08 – < 4891a50f5ed8bfcb8f2a4b816b0676f398687783
  • affected fb9987d0f748c983bb795a86f47522313f701a08 – < b383e8abed41cc6ff1a3b34de75df9397fa4878c

• Linux · Linux

  • affected 2.6.35
  • unaffected < 2.6.35
  • unaffected 4.14.296 – ≤ 4.14.*
  • unaffected 4.19.262 – ≤ 4.19.*
  • unaffected 5.4.220 – ≤ 5.4.*
  • unaffected 5.10.150 – ≤ 5.10.*
  • unaffected 5.15.75 – ≤ 5.15.*
  • unaffected 5.19.17 – ≤ 5.19.*
  • unaffected 6.0.3 – ≤ 6.0.*
  • unaffected 6.1 – ≤ *

References (8)

• https://git.kernel.org/stable/c/f3d2a3b7e290d0bdbddfcee5a6c3d922e2b7e02a (opens in a new tab)
• https://git.kernel.org/stable/c/84242f15f911f34aec9b22f99d1e9bff19723dbe (opens in a new tab)
• https://git.kernel.org/stable/c/2c485f4f2a64258acc5228e78ffb828c68d9e770 (opens in a new tab)
• https://git.kernel.org/stable/c/9661724f6206bd606ecf13acada676a9975d230b (opens in a new tab)
• https://git.kernel.org/stable/c/b1b4144508adfc585e43856b31baaf9008a3beb4 (opens in a new tab)
• https://git.kernel.org/stable/c/0d2649b288b7b9484e3d4380c0d6c4720a17e473 (opens in a new tab)
• https://git.kernel.org/stable/c/4891a50f5ed8bfcb8f2a4b816b0676f398687783 (opens in a new tab)
• https://git.kernel.org/stable/c/b383e8abed41cc6ff1a3b34de75df9397fa4878c (opens in a new tab)

Sources

The same CVE in the primary databases and aggregators, to check against.

• CVE.org record (opens in a new tab)
• CVE List JSON (GitHub) (opens in a new tab)
• NVD (opens in a new tab)
• FIRST EPSS (opens in a new tab)
• OSV.dev (opens in a new tab)
• GitHub Advisories (opens in a new tab)
• CIRCL Vulnerability-Lookup (opens in a new tab)

Badge for a README or a ticket

[![CVE-2022-50709](https://trackcve.app/badge/CVE-2022-50709.svg)](https://trackcve.app/cve/CVE-2022-50709)

Record last updated 11 May 2026, 19:23 UTC.