{"id":"DEBIAN-CVE-2025-21943","details":"In the Linux kernel, the following vulnerability has been resolved:  gpio: aggregator: protect driver attr handlers against module unload  Both new_device_store and delete_device_store touch module global resources (e.g. gpio_aggregator_lock). To prevent race conditions with module unload, a reference needs to be held.  Add try_module_get() in these handlers.  For new_device_store, this eliminates what appears to be the most dangerous scenario: if an id is allocated from gpio_aggregator_idr but platform_device_register has not yet been called or completed, a concurrent module unload could fail to unregister/delete the device, leaving behind a dangling platform device/GPIO forwarder. This can result in various issues. The following simple reproducer demonstrates these problems:    #!/bin/bash   while :; do     # note: whether 'gpiochip0 0' exists or not does not matter.     echo 'gpiochip0 0' \u003e /sys/bus/platform/drivers/gpio-aggregator/new_device   done &   while :; do     modprobe gpio-aggregator     modprobe -r gpio-aggregator   done &   wait    Starting with the following warning, several kinds of warnings will appear   and the system may become unstable:    ------------[ cut here ]------------   list_del corruption, ffff888103e2e980-\u003enext is LIST_POISON1 (dead000000000100)   WARNING: CPU: 1 PID: 1327 at lib/list_debug.c:56 __list_del_entry_valid_or_report+0xa3/0x120   [...]   RIP: 0010:__list_del_entry_valid_or_report+0xa3/0x120   [...]   Call Trace:    \u003cTASK\u003e    ? __list_del_entry_valid_or_report+0xa3/0x120    ? __warn.cold+0x93/0xf2    ? __list_del_entry_valid_or_report+0xa3/0x120    ? report_bug+0xe6/0x170    ? __irq_work_queue_local+0x39/0xe0    ? handle_bug+0x58/0x90    ? exc_invalid_op+0x13/0x60    ? asm_exc_invalid_op+0x16/0x20    ? __list_del_entry_valid_or_report+0xa3/0x120    gpiod_remove_lookup_table+0x22/0x60    new_device_store+0x315/0x350 [gpio_aggregator]    kernfs_fop_write_iter+0x137/0x1f0    vfs_write+0x262/0x430    ksys_write+0x60/0xd0    do_syscall_64+0x6c/0x180    entry_SYSCALL_64_after_hwframe+0x76/0x7e    [...]    \u003c/TASK\u003e   ---[ end trace 0000000000000000 ]---","modified":"2026-09-01T16:06:10.389348597Z","published":"2025-04-01T16:15:25.400Z","upstream":["CVE-2025-21943"],"references":[{"type":"ADVISORY","url":"https://security-tracker.debian.org/tracker/CVE-2025-21943"}],"affected":[{"package":{"name":"linux","ecosystem":"Debian:12","purl":"pkg:deb/debian/linux?arch=source&distro=bookworm"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"6.1.133-1"}]}],"versions":["6.1.106-1","6.1.106-2","6.1.106-3","6.1.112-1","6.1.115-1","6.1.119-1","6.1.123-1","6.1.124-1","6.1.128-1","6.1.129-1","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","6.1.99-1"],"ecosystem_specific":{"urgency":"not yet assigned"},"database_specific":{"source":"https://storage.googleapis.com/osv-test-debian-osv/debian-cve-osv/DEBIAN-CVE-2025-21943.json"}},{"package":{"name":"linux","ecosystem":"Debian:13","purl":"pkg:deb/debian/linux?arch=source&distro=trixie"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"6.12.19-1"}]}],"ecosystem_specific":{"urgency":"not yet assigned"},"database_specific":{"source":"https://storage.googleapis.com/osv-test-debian-osv/debian-cve-osv/DEBIAN-CVE-2025-21943.json"}},{"package":{"name":"linux","ecosystem":"Debian:14","purl":"pkg:deb/debian/linux?arch=source&distro=forky"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"6.12.19-1"}]}],"ecosystem_specific":{"urgency":"not yet assigned"},"database_specific":{"source":"https://storage.googleapis.com/osv-test-debian-osv/debian-cve-osv/DEBIAN-CVE-2025-21943.json"}}],"schema_version":"1.9.0","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H"}]}