CVE-2026-43465

Description

In the Linux kernel, the following vulnerability has been resolved: net/mlx5e: RX, Fix XDP multi-buf frag counting for striding RQ XDP multi-buf programs can modify the layout of the XDP buffer when the program calls bpf_xdp_pull_data() or bpf_xdp_adjust_tail(). The referenced commit in the fixes tag corrected the assumption in the mlx5 driver that the XDP buffer layout doesn-t change during a program execution. However, this fix introduced another issue: the dropped fragments still need to be counted on the driver side to avoid page fragment reference counting issues. The issue was discovered by the drivers/net/xdp.py selftest, more specifically the test_xdp_native_tx_mb: - The mlx5 driver allocates a page_pool page and initializes it with a frag counter of 64 (pp_ref_count=64) and the internal frag counter to 0. - The test sends one packet with no payload. - On RX (mlx5e_skb_from_cqe_mpwrq_nonlinear()), mlx5 configures the XDP buffer with the packet data starting in the first fragmen...