Hi, On Thu, May 23, 2024 at 06:51:01PM +0200, jianqiang wang wrote: > 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.
Thanks for noting this. I've just sent a series fixing the drivers you explicitly mentioned. Additionally I have checked a few other drivers and it seems at least the smc91111 driver has this issue as well. Are you aware of other drivers? Sascha -- Pengutronix e.K. | | Steuerwalder Str. 21 | http://www.pengutronix.de/ | 31137 Hildesheim, Germany | Phone: +49-5121-206917-0 | Amtsgericht Hildesheim, HRA 2686 | Fax: +49-5121-206917-5555 |
