{"id":"CVE-2025-39736","summary":"mm/kmemleak: avoid deadlock by moving pr_warn() outside kmemleak_lock","details":"In the Linux kernel, the following vulnerability has been resolved:\n\nmm/kmemleak: avoid deadlock by moving pr_warn() outside kmemleak_lock\n\nWhen netpoll is enabled, calling pr_warn_once() while holding\nkmemleak_lock in mem_pool_alloc() can cause a deadlock due to lock\ninversion with the netconsole subsystem.  This occurs because\npr_warn_once() may trigger netpoll, which eventually leads to\n__alloc_skb() and back into kmemleak code, attempting to reacquire\nkmemleak_lock.\n\nThis is the path for the deadlock.\n\nmem_pool_alloc()\n  -\u003e raw_spin_lock_irqsave(&kmemleak_lock, flags);\n      -\u003e pr_warn_once()\n          -\u003e netconsole subsystem\n\t     -\u003e netpoll\n\t         -\u003e __alloc_skb\n\t\t   -\u003e __create_object\n\t\t     -\u003e raw_spin_lock_irqsave(&kmemleak_lock, flags);\n\nFix this by setting a flag and issuing the pr_warn_once() after\nkmemleak_lock is released.","modified":"2026-04-02T12:48:07.852161Z","published":"2025-09-11T16:52:11.772Z","database_specific":{"osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2025/39xxx/CVE-2025-39736.json","cna_assigner":"Linux"},"references":[{"type":"WEB","url":"https://git.kernel.org/stable/c/08f70be5e406ce47c822f2dd11c1170ca259605b"},{"type":"WEB","url":"https://git.kernel.org/stable/c/1da95d3d4b7b1d380ebd87b71a61e7e6aed3265d"},{"type":"WEB","url":"https://git.kernel.org/stable/c/47b0f6d8f0d2be4d311a49e13d2fd5f152f492b2"},{"type":"WEB","url":"https://git.kernel.org/stable/c/4b0151e1d468eb2667c37b7af99b3c075072d334"},{"type":"WEB","url":"https://git.kernel.org/stable/c/62879faa8efe8d8a9c7bf7606ee9c068012d7dac"},{"type":"WEB","url":"https://git.kernel.org/stable/c/a0854de00ce2ee27edf39037e7836ad580eb3350"},{"type":"WEB","url":"https://git.kernel.org/stable/c/a181b228b37a6a5625dad2bb4265bb7abb673e9f"},{"type":"WEB","url":"https://git.kernel.org/stable/c/c7b6ea0ede687e7460e593c5ea478f50aa41682a"},{"type":"WEB","url":"https://git.kernel.org/stable/c/f249d32bb54876b4b6c3ae071af8ddca77af390b"},{"type":"WEB","url":"https://lists.debian.org/debian-lts-announce/2025/10/msg00007.html"},{"type":"WEB","url":"https://lists.debian.org/debian-lts-announce/2025/10/msg00008.html"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2025/39xxx/CVE-2025-39736.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2025-39736"},{"type":"PACKAGE","url":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","events":[{"introduced":"c5665868183fec689dbab9fb8505188b2c4f0757"},{"fixed":"c7b6ea0ede687e7460e593c5ea478f50aa41682a"},{"fixed":"4b0151e1d468eb2667c37b7af99b3c075072d334"},{"fixed":"f249d32bb54876b4b6c3ae071af8ddca77af390b"},{"fixed":"62879faa8efe8d8a9c7bf7606ee9c068012d7dac"},{"fixed":"1da95d3d4b7b1d380ebd87b71a61e7e6aed3265d"},{"fixed":"a0854de00ce2ee27edf39037e7836ad580eb3350"},{"fixed":"08f70be5e406ce47c822f2dd11c1170ca259605b"},{"fixed":"a181b228b37a6a5625dad2bb4265bb7abb673e9f"},{"fixed":"47b0f6d8f0d2be4d311a49e13d2fd5f152f492b2"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2025-39736.json"}}],"schema_version":"1.7.5"}