{"id":"DEBIAN-CVE-2024-40910","details":"In the Linux kernel, the following vulnerability has been resolved:  ax25: Fix refcount imbalance on inbound connections  When releasing a socket in ax25_release(), we call netdev_put() to decrease the refcount on the associated ax.25 device. However, the execution path for accepting an incoming connection never calls netdev_hold(). This imbalance leads to refcount errors, and ultimately to kernel crashes.  A typical call trace for the above situation will start with one of the following errors:      refcount_t: decrement hit 0; leaking memory.     refcount_t: underflow; use-after-free.  And will then have a trace like:      Call Trace:     \u003cTASK\u003e     ? show_regs+0x64/0x70     ? __warn+0x83/0x120     ? refcount_warn_saturate+0xb2/0x100     ? report_bug+0x158/0x190     ? prb_read_valid+0x20/0x30     ? handle_bug+0x3e/0x70     ? exc_invalid_op+0x1c/0x70     ? asm_exc_invalid_op+0x1f/0x30     ? refcount_warn_saturate+0xb2/0x100     ? refcount_warn_saturate+0xb2/0x100     ax25_release+0x2ad/0x360     __sock_release+0x35/0xa0     sock_close+0x19/0x20     [...]  On reboot (or any attempt to remove the interface), the kernel gets stuck in an infinite loop:      unregister_netdevice: waiting for ax0 to become free. Usage count = 0  This patch corrects these issues by ensuring that we call netdev_hold() and ax25_dev_hold() for new connections in ax25_accept(). This makes the logic leading to ax25_accept() match the logic for ax25_bind(): in both cases we increment the refcount, which is ultimately decremented in ax25_release().","modified":"2026-09-15T09:02:57.178468025Z","published":"2024-07-12T13:15:14.213Z","upstream":["CVE-2024-40910"],"references":[{"type":"ADVISORY","url":"https://security-tracker.debian.org/tracker/CVE-2024-40910"}],"affected":[{"package":{"name":"linux","ecosystem":"Debian:12","purl":"pkg:deb/debian/linux?arch=source&distro=bookworm"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"6.1.99-1"}]}],"versions":["6.1.27-1","6.1.37-1","6.1.38-1","6.1.38-2","6.1.38-2~bpo11+1","6.1.38-3","6.1.38-4","6.1.38-4~bpo11+1","6.1.52-1","6.1.55-1","6.1.55-1~bpo11+1","6.1.64-1","6.1.66-1","6.1.67-1","6.1.69-1","6.1.69-1~bpo11+1","6.1.76-1","6.1.76-1~bpo11+1","6.1.82-1","6.1.85-1","6.1.90-1","6.1.90-1~bpo11+1","6.1.94-1","6.1.94-1~bpo11+1","6.1.98-1"],"ecosystem_specific":{"urgency":"not yet assigned"},"database_specific":{"source":"https://storage.googleapis.com/osv-test-debian-osv/debian-cve-osv/DEBIAN-CVE-2024-40910.json"}},{"package":{"name":"linux","ecosystem":"Debian:13","purl":"pkg:deb/debian/linux?arch=source&distro=trixie"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"6.9.7-1"}]}],"ecosystem_specific":{"urgency":"not yet assigned"},"database_specific":{"source":"https://storage.googleapis.com/osv-test-debian-osv/debian-cve-osv/DEBIAN-CVE-2024-40910.json"}},{"package":{"name":"linux","ecosystem":"Debian:14","purl":"pkg:deb/debian/linux?arch=source&distro=forky"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"6.9.7-1"}]}],"ecosystem_specific":{"urgency":"not yet assigned"},"database_specific":{"source":"https://storage.googleapis.com/osv-test-debian-osv/debian-cve-osv/DEBIAN-CVE-2024-40910.json"}}],"schema_version":"1.9.0","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H"}]}