Dear Barebox devlopers, I found several heap overflow vulnerabilities in Barebox. The Barebox implementation assumes that the network packet received is less than PKTSIZE, that is 1536 bytes. For example, the /net/net.c file ping_reply function assumes that the packet received is 1536 bytes and allocates a 1536 bytes buffer then copies the packet data into the buffer. However, in the driver layer, it lacks a proper check of the packet length. For example, in drivers/net/cs8900.c cs8900_probe function, it allocates a PKTSIZE buffer and assigns it to rx_buf. In cs8900_recv function, the length is read from the device register: len = readw(priv->regs + CS8900_RTDATA0); After that, the data is read from the register in a loop without a boundary check. The same vulnerability happens to the following drivers: drivers/net/ks8851_mll.c function ks8851_rx_frame, it only and the packet length with RXFHBCR_CNT_MASK (4095 bytes,) which is not consistent with the upper layer length check. drivers/net/liteeth.c function liteeth_eth_rx, It checks if the length is larger than 2048 which is inconsistent with the upper layer. drivers/net/smc911x.c function smc911x_eth_rx. The packet length is read from the register without checking. It would be good to add a proper and consistent boundary check for these drivers otherwise it will lead to potential heap overflow vulnerability. Best regards
