CyberRota Analysis
AI-GeneratedThe vulnerability affects the Linux kernel's interconnect subsystem, specifically in the functions `icc_get()` and `of_icc_get_by_index()`, where improper error handling leads to a use-after-free condition due to dangling pointers in linked lists. This flaw can result in memory corruption, potentially allowing an attacker to exploit the system through subsequent calls to `icc_get()` or `icc_set_bw()`. Organizations using affected Linux kernel versions should prioritize patching this vulnerability to mitigate risks associated with memory corruption and potential system instability.
Original NVD Description
In the Linux kernel, the following vulnerability has been resolved: interconnect: Fix use after free in icc_get() and of_icc_get_by_index() In of_icc_get_by_index() and icc_get(), if the dynamic allocation for path->name fails via kasprintf(), the error handling path directly calls kfree(path) to free the path object and returns an error. However, prior to this point, path_find() calls path_init(), which already links the path's requests into the req_list of the respective interconnect nodes via hlist_add_head(). Directly invoking kfree(path) leaves dangling pointers in the hlist. A subsequent call to icc_get() or icc_set_bw() will traverse or modify these corrupted lists, triggering a slab use afterfree. KASAN report showing the vulnerability when reproducing via debugfs: BUG: KASAN: slab-use-after-free in path_find+0x6f8/0xcfc Write of size 8 at addr fff000000d43f748 by task sh/1 ... Call trace: kasan_report+0xac/0xfc path_find+0x6f8/0xcfc icc_get+0x148/0x380 icc_get_set+0xf8/0x2d0 ... Freed by task 1: kfree+0x1a0/0x4a4 icc_get+0x2cc/0x380 icc_get_set+0xf8/0x2d0 Fix this by replacing kfree(path) with the proper teardown function, icc_put(path), which safely removes the requests from the req_list using hlist_del() and drops the provider usage references before freeing the memory. Additionally, in icc_get(), ensure that the icc_lock mutex is released prior to calling icc_put(path) to avoid a deadlock, as icc_put() internally acquires the same lock.