Executive brief
A memory leak vulnerability exists in the Altera Ethernet driver within the Linux kernel. When the system encounters a specific hardware communication error (DMA mapping failure), it fails to release allocated memory. Over time, this can lead to a depletion of system resources, potentially causing the device to slow down or crash, impacting operational availability.
Technical details
A memory leak (CWE-401) exists in the Altera Triple-Speed Ethernet (TSE) driver (drivers/net/ethernet/altera/altera_tse_main.c) within the Linux kernel. The vulnerability is located in the tse_start_xmit() function, where a failure in dma_map_single() results in the function returning NETDEV_TX_OK without freeing the associated socket buffer (skb). Because the networking stack is notified that the packet was successfully consumed, the memory is never reclaimed. An attacker with local access could potentially trigger this condition to exhaust system memory, leading to a denial-of-service. Patches have been released across multiple stable kernel branches to include the missing dev_kfree_skb_any() call.
Affected products
- Linux Linux Kernel versions before 6.9.1
- Siemens SIMATIC S7-1500 CPU 1518-4 PN/DP MFP V3.1.5, V3.1.6
Timeline
- 2026-04-01: disclosed: Initial patch submitted by David Carlier
- 2026-04-24: advisory: NVD publication date
References
- https://git.kernel.org/stable/c/2eb9d67704ca8f1101f7435b85f113ede471f9f2
- https://git.kernel.org/stable/c/3aca300e88afe56afb000cdc4c65383014fb17f9
- https://git.kernel.org/stable/c/60f462cd2716d86bd2174f9d5e035c9278f30480
- https://git.kernel.org/stable/c/6dede3967619b5944003227a5d09fdc21ed57d10
- https://git.kernel.org/stable/c/9f3ec44aeb58501d11834048d5d0dbaeacb6d4e7
- https://git.kernel.org/stable/c/ae2cd46f57f422b51aedd406ff5d75cbff401d5d
- https://git.kernel.org/stable/c/cb1d318702fdf643061350d164250198df4116f2