CVE-2023-53529

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

wifi: rtw88: Fix memory leak in rtw88_usb

Kmemleak shows the following leak arising from routine in the usb probe routine:

unreferenced object 0xffff895cb29bba00 (size 512): comm "(udev-worker)", pid 534, jiffies 4294903932 (age 102751.088s) hex dump (first 32 bytes): 77 30 30 30 00 00 00 00 02 2f 2d 2b 30 00 00 00 w000...../-+0... 02 00 2a 28 00 00 00 00 ff 55 ff ff ff 00 00 00 ..*(.....U...... backtrace: [<ffffffff9265fa36>] kmalloc_trace+0x26/0x90 [<ffffffffc17eec41>] rtw_usb_probe+0x2f1/0x680 [rtw_usb] [<ffffffffc03e19fd>] usb_probe_interface+0xdd/0x2e0 [usbcore] [<ffffffff92b4f2fe>] really_probe+0x18e/0x3d0 [<ffffffff92b4f5b8>] __driver_probe_device+0x78/0x160 [<ffffffff92b4f6bf>] driver_probe_device+0x1f/0x90 [<ffffffff92b4f8df>] __driver_attach+0xbf/0x1b0 [<ffffffff92b4d350>] bus_for_each_dev+0x70/0xc0 [<ffffffff92b4e51e>] bus_add_driver+0x10e/0x210 [<ffffffff92b50935>] driver_register+0x55/0xf0 [<ffffffffc03e0708>] usb_register_driver+0x88/0x140 [usbcore] [<ffffffff92401153>] do_one_initcall+0x43/0x210 [<ffffffff9254f42a>] do_init_module+0x4a/0x200 [<ffffffff92551d1c>] __do_sys_finit_module+0xac/0x120 [<ffffffff92ee6626>] do_syscall_64+0x56/0x80 [<ffffffff9300006a>] entry_SYSCALL_64_after_hwframe+0x46/0xb0

The leak was verified to be real by unloading the driver, which resulted in a dangling pointer to the allocation.

The allocated memory is freed in rtw_usb_intf_deinit().

The patch fixes a memory leak in the rtw88_usb driver by freeing rtwusb->usb_data in rtw_usb_intf_deinit(). Previously, allocations made during probe were not released on interface teardown, leading to leaked kernel memory reported by kmemleak. Impact is limited to availability (resource consumption) with no confidentiality or integrity effect. An attacker could only accumulate small leaks via repeated device (un)plug or privileged driver rebind cycles.

The CVSS score(s) listed for this vulnerability do not reflect the associated product's status, and are included for informational purposes to better understand the severity of this vulnerability.