Bug 2492745 (CVE-2026-53235) - CVE-2026-53235 kernel: net: add pskb_may_pull() to skb_gro_receive_list()
Summary: CVE-2026-53235 kernel: net: add pskb_may_pull() to skb_gro_receive_list()
Keywords:
Status: NEW
Alias: CVE-2026-53235
Product: Security Response
Classification: Other
Component: vulnerability
Version: unspecified
Hardware: All
OS: Linux
medium
medium
Target Milestone: ---
Assignee: Product Security
QA Contact:
URL:
Whiteboard:
Depends On:
Blocks:
TreeView+ depends on / blocked
 
Reported: 2026-06-25 10:03 UTC by OSIDB Bzimport
Modified: 2026-09-08 07:19 UTC (History)
2 users (show)

Fixed In Version:
Clone Of:
Environment:
Last Closed:
Embargoed:


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System ID Private Priority Status Summary Last Updated
Red Hat Product Errata RHSA-2026:64775 0 None None None 2026-09-08 07:19:49 UTC

Description OSIDB Bzimport 2026-06-25 10:03:31 UTC
In the Linux kernel, the following vulnerability has been resolved:

net: add pskb_may_pull() to skb_gro_receive_list()

skb_gro_receive_list() calls skb_pull(skb, skb_gro_offset(skb)) without
first ensuring the data is in the linear area via pskb_may_pull(). When
the skb arrives via napi_gro_frags(), skb_headlen can be 0 (all data in
page fragments) while skb_gro_offset is non-zero (after IP+TCP header
parsing). The skb_pull() then decrements skb->len by skb_gro_offset
but skb->data_len stays unchanged, hitting BUG_ON(skb->len < skb->data_len)
in __skb_pull().

The UDP fraglist GRO path already contains this guard at
udp_offload.c:749. Adding it to skb_gro_receive_list() itself provides
centralized protection for all callers (TCP, UDP, and any future
protocols), and ensures the precondition of skb_pull() is satisfied
before it is called.

On pskb_may_pull() failure, set NAPI_GRO_CB(skb)->flush = 1 so the
skb is not held as a new GRO head and is instead delivered through the
normal receive path, matching the UDP handling.

Comment 4 errata-xmlrpc 2026-09-08 07:19:48 UTC
This issue has been addressed in the following products:

  Red Hat Enterprise Linux 10

Via RHSA-2026:64775 https://access.redhat.com/errata/RHSA-2026:64775


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