CVE-2025-68352

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

spi: ch341: fix out-of-bounds memory access in ch341_transfer_one

Discovered by Atuin - Automated Vulnerability Discovery Engine.

The len variable is calculated as min(32, trans->len + 1), which includes the 1-byte command header.

When copying data from trans->tx_buf to ch341->tx_buf + 1, using len as the length is incorrect because:

1. It causes an out-of-bounds read from trans->tx_buf (which has size trans->len, i.e., len - 1 in this context).
2. It can cause an out-of-bounds write to ch341->tx_buf if len is CH341_PACKET_LENGTH (32). Writing 32 bytes to ch341->tx_buf + 1 overflows the buffer.

Fix this by copying len - 1 bytes.

Affected Software

References

• https://git.kernel.org/stable/c/545d1287e40a55242f6ab68bcc1ba3b74088b1bc
• https://git.kernel.org/stable/c/81841da1f30f66a850cc8796d99ba330aad9d696
• https://git.kernel.org/stable/c/cad6c0fd6f3c0e76a1f75df4bce3b08a13f08974
• https://git.kernel.org/stable/c/ea1e43966cd03098fcd5f0d72e6c2901d45fa08d