Bugzilla – Bug 1223800
VUL-0: CVE-2024-27005: kernel: interconnect: Don't access req_list while it's being manipulated
Last modified: 2024-05-06 07:42:01 UTC
In the Linux kernel, the following vulnerability has been resolved: interconnect: Don't access req_list while it's being manipulated The icc_lock mutex was split into separate icc_lock and icc_bw_lock mutexes in [1] to avoid lockdep splats. However, this didn't adequately protect access to icc_node::req_list. The icc_set_bw() function will eventually iterate over req_list while only holding icc_bw_lock, but req_list can be modified while only holding icc_lock. This causes races between icc_set_bw(), of_icc_get(), and icc_put(). Example A: CPU0 CPU1 ---- ---- icc_set_bw(path_a) mutex_lock(&icc_bw_lock); icc_put(path_b) mutex_lock(&icc_lock); aggregate_requests() hlist_for_each_entry(r, ... hlist_del(... <r = invalid pointer> Example B: CPU0 CPU1 ---- ---- icc_set_bw(path_a) mutex_lock(&icc_bw_lock); path_b = of_icc_get() of_icc_get_by_index() mutex_lock(&icc_lock); path_find() path_init() aggregate_requests() hlist_for_each_entry(r, ... hlist_add_head(... <r = invalid pointer> Fix this by ensuring icc_bw_lock is always held before manipulating icc_node::req_list. The additional places icc_bw_lock is held don't perform any memory allocations, so we should still be safe from the original lockdep splats that motivated the separate locks. [1] commit af42269c3523 ("interconnect: Fix locking for runpm vs reclaim") References: http://web.nvd.nist.gov/view/vuln/detail?vulnId=CVE-2024-27005 https://www.cve.org/CVERecord?id=CVE-2024-27005 https://git.kernel.org/stable/c/4c65507121ea8e0b47fae6d2049c8688390d46b6 https://git.kernel.org/stable/c/d0d04efa2e367921654b5106cc5c05e3757c2b42 https://git.kernel.org/stable/c/de1bf25b6d771abdb52d43546cf57ad775fb68a1 https://git.kernel.org/pub/scm/linux/security/vulns.git/plain/cve/published/2024/CVE-2024-27005.mbox https://bugzilla.redhat.com/show_bug.cgi?id=2278289 https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/4EZ6PJW7VOZ224TD7N4JZNU6KV32ZJ53/ https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/DAMSOZXJEPUOXW33WZYWCVAY7Z5S7OOY/ https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/GCBZZEC7L7KTWWAS2NLJK6SO3IZIL4WW/
All done, closing.