Summary

In the Linux kernel, the following vulnerability has been resolved: net: skbuff: preserve shared-frag marker during coalescing skb_try_coalesce() can attach paged frags from @from to @to. If @from has SKBFL_SHARED_FRAG set, the resulting @to skb can contain the same externally-owned or page-cache-backed frags, but the shared-frag marker is currently lost. That breaks the invariant relied on by later in-place writers. In particular, ESP input checks skb_has_shared_frag() before deciding whether an uncloned nonlinear skb can skip skb_cow_data(). If TCP receive coalescing has moved shared frags into an unmarked skb, ESP can see skb_has_shared_frag() as false and decrypt in place over page-cache backed frags. Propagate SKBFL_SHARED_FRAG when skb_try_coalesce() transfers paged frags. The tailroom copy path does not need the marker because it copies bytes into @to's linear data rather than transferring frag descriptors. 

Products Affected

• Brocade SANnav base OS (OVA versions)  before 3.0.0a and SANnav 3.0.0 through 3.0.1

Products Not Affected

• Brocade Fabric OS [VEX:Vulnerable_code_not_in_execute_path]
• Brocade SANnav Non-OVA standard deployment [VEX:Vulnerable_code_not_in_execute_path]
• Brocade ASCG [VEX:Vulnerable_code_not_in_execute_path]

Solution

• Security update provided in Brocade SANnav 3.0.0a OVA, OVA OS patches - 8.x (sannav_ova_8x_os_06_2026) and 9x (sannav_ova_9x_os_06_2026).

Revision History

Disclaimer

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