Overview
About vulnerability
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.
Details
- Affected product:
- AlmaLinux 9.2 ESU , CentOS 8.4 ELS , CentOS 8.5 ELS
- Affected packages:
- kernel @ 4.18.0 (+2 more)
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.