Bug 2460697 (CVE-2026-31501)

Summary: CVE-2026-31501 kernel: net: ti: icssg-prueth: fix use-after-free of CPPI descriptor in RX path
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security <prodsec-ir-bot>
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OS: Linux   
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A flaw was found in the Linux kernel's `net: ti: icssg-prueth` driver. This use-after-free vulnerability occurs in the receive (RX) path, where a data structure (CPPI descriptor) is released from memory before all necessary operations on its contents are complete. A remote attacker could exploit this by sending specially crafted network packets, potentially leading to memory corruption and system instability or denial of service.
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Description OSIDB Bzimport 2026-04-22 15:06:04 UTC 
In the Linux kernel, the following vulnerability has been resolved:

net: ti: icssg-prueth: fix use-after-free of CPPI descriptor in RX path

cppi5_hdesc_get_psdata() returns a pointer into the CPPI descriptor.
In both emac_rx_packet() and emac_rx_packet_zc(), the descriptor is
freed via k3_cppi_desc_pool_free() before the psdata pointer is used
by emac_rx_timestamp(), which dereferences psdata[0] and psdata[1].
This constitutes a use-after-free on every received packet that goes
through the timestamp path.

Defer the descriptor free until after all accesses through the psdata
pointer are complete. For emac_rx_packet(), move the free into the
requeue label so both early-exit and success paths free the descriptor
after all accesses are done. For emac_rx_packet_zc(), move the free to
the end of the loop body after emac_dispatch_skb_zc() (which calls
emac_rx_timestamp()) has returned.
Comment 1 Keith Grant 2026-04-22 19:26:14 UTC 
Upstream advisory:
https://lore.kernel.org/linux-cve-announce/2026042205-CVE-2026-31501-113b@gregkh/T