CVE-2022-50131

In the Linux kernel, the following vulnerability has been resolved:

HID: mcp2221: prevent a buffer overflow in mcp_smbus_write()

Smatch Warning: drivers/hid/hid-mcp2221.c:388 mcp_smbus_write() error: __memcpy() &mcp->txbuf[5] too small (59 vs 255) drivers/hid/hid-mcp2221.c:388 mcp_smbus_write() error: __memcpy() buf too small (34 vs 255)

The len variable can take a value between 0-255 as it can come from data->block[0] and it is user data. So add an bound check to prevent a buffer overflow in memcpy().

Affected Software

References

• https://git.kernel.org/stable/c/3c0f8a59f2cc8841ee6653399a77f4f3e6e9a270
• https://git.kernel.org/stable/c/62ac2473553a00229e67bdf3cb023b62cf7f5a9a
• https://git.kernel.org/stable/c/6402116a7b5ec80fa40fd145a80c813019cd555f
• https://git.kernel.org/stable/c/66c8e816f2f2ca4a61b406503bd10bad1b35f72f
• https://git.kernel.org/stable/c/91443c669d280937968f0aa4edefa741cfe35314