CVE-2023-53524

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

wifi: iwlwifi: pcie: Fix integer overflow in iwl_write_to_user_buf

An integer overflow occurs in the iwl_write_to_user_buf() function, which is called by the iwl_dbgfs_monitor_data_read() function.

static bool iwl_write_to_user_buf(char __user *user_buf, ssize_t count, void *buf, ssize_t *size, ssize_t *bytes_copied) { int buf_size_left = count - *bytes_copied;

buf_size_left = buf_size_left - (buf_size_left % sizeof(u32));
if (*size > buf_size_left)
	*size = buf_size_left;

If the user passes a SIZE_MAX value to the ssize_t count parameter, the ssize_t count parameter is assigned to int buf_size_left. Then compare *size with buf_size_left . Here, buf_size_left is a negative number, so *size is assigned buf_size_left and goes into the third argument of the copy_to_user function, causing a heap overflow.

This is not a security vulnerability because iwl_dbgfs_monitor_data_read() is a debugfs operation with 0400 privileges.

Affected Software

References

• https://git.kernel.org/stable/c/059e426d666a41e26b184c177c1ca3ee2d6fa1b6
• https://git.kernel.org/stable/c/0ad8dd870aa187d0c21d032bb2c6433559075eec
• https://git.kernel.org/stable/c/58d1b717879bfeabe09b35e41ad667c79933eb2e
• https://git.kernel.org/stable/c/82f877ec9b041edc4c7c509c605cc3393d837bf0
• https://git.kernel.org/stable/c/de78456976026102babe66258c228691ca5677c0
• https://git.kernel.org/stable/c/eb1ef44efac797b384d361a76e33f77027c29a14