{"id":"DEBIAN-CVE-2025-40147","details":"In the Linux kernel, the following vulnerability has been resolved:  blk-throttle: fix access race during throttle policy activation  On repeated cold boots we occasionally hit a NULL pointer crash in blk_should_throtl() when throttling is consulted before the throttle policy is fully enabled for the queue. Checking only q-\u003etd != NULL is insufficient during early initialization, so blkg_to_pd() for the throttle policy can still return NULL and blkg_to_tg() becomes NULL, which later gets dereferenced.   Unable to handle kernel NULL pointer dereference  at virtual address 0000000000000156  ...  pc : submit_bio_noacct+0x14c/0x4c8  lr : submit_bio_noacct+0x48/0x4c8  sp : ffff800087f0b690  x29: ffff800087f0b690 x28: 0000000000005f90 x27: ffff00068af393c0  x26: 0000000000080000 x25: 000000000002fbc0 x24: ffff000684ddcc70  x23: 0000000000000000 x22: 0000000000000000 x21: 0000000000000000  x20: 0000000000080000 x19: ffff000684ddcd08 x18: ffffffffffffffff  x17: 0000000000000000 x16: ffff80008132a550 x15: 0000ffff98020fff  x14: 0000000000000000 x13: 1fffe000d11d7021 x12: ffff000688eb810c  x11: ffff00077ec4bb80 x10: ffff000688dcb720 x9 : ffff80008068ef60  x8 : 00000a6fb8a86e85 x7 : 000000000000111e x6 : 0000000000000002  x5 : 0000000000000246 x4 : 0000000000015cff x3 : 0000000000394500  x2 : ffff000682e35e40 x1 : 0000000000364940 x0 : 000000000000001a  Call trace:   submit_bio_noacct+0x14c/0x4c8   verity_map+0x178/0x2c8   __map_bio+0x228/0x250   dm_submit_bio+0x1c4/0x678   __submit_bio+0x170/0x230   submit_bio_noacct_nocheck+0x16c/0x388   submit_bio_noacct+0x16c/0x4c8   submit_bio+0xb4/0x210   f2fs_submit_read_bio+0x4c/0xf0   f2fs_mpage_readpages+0x3b0/0x5f0   f2fs_readahead+0x90/0xe8  Tighten blk_throtl_activated() to also require that the throttle policy bit is set on the queue:    return q-\u003etd != NULL &&          test_bit(blkcg_policy_throtl.plid, q-\u003eblkcg_pols);  This prevents blk_should_throtl() from accessing throttle group state until policy data has been attached to blkgs.","modified":"2026-08-27T22:48:56.659914052Z","published":"2025-11-12T11:15:44.600Z","upstream":["CVE-2025-40147"],"references":[{"type":"ADVISORY","url":"https://security-tracker.debian.org/tracker/CVE-2025-40147"}],"affected":[{"package":{"name":"linux","ecosystem":"Debian:13","purl":"pkg:deb/debian/linux?arch=source&distro=trixie"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"6.12.85-1"}]}],"versions":["6.12.38-1","6.12.41-1","6.12.43-1","6.12.43-1~bpo12+1","6.12.48-1","6.12.57-1","6.12.57-1~bpo12+1","6.12.63-1","6.12.63-1~bpo12+1","6.12.69-1","6.12.69-1~bpo12+1","6.12.73-1","6.12.73-1~bpo12+1","6.12.74-1","6.12.74-2","6.12.74-2~bpo12+1","6.12.85-1~bpo12+1"],"ecosystem_specific":{"urgency":"not yet assigned"},"database_specific":{"source":"https://storage.googleapis.com/osv-test-debian-osv/debian-cve-osv/DEBIAN-CVE-2025-40147.json"}},{"package":{"name":"linux","ecosystem":"Debian:14","purl":"pkg:deb/debian/linux?arch=source&distro=forky"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"6.17.6-1"}]}],"versions":["6.12.100-1","6.12.101-1","6.12.105-1","6.12.38-1","6.12.41-1","6.12.43-1","6.12.43-1~bpo12+1","6.12.48-1","6.12.57-1","6.12.57-1~bpo12+1","6.12.63-1","6.12.63-1~bpo12+1","6.12.69-1","6.12.69-1~bpo12+1","6.12.73-1","6.12.73-1~bpo12+1","6.12.74-1","6.12.74-2","6.12.74-2~bpo12+1","6.12.85-1","6.12.85-1~bpo12+1","6.12.86-1","6.12.86-1~bpo12+1","6.12.88-1","6.12.88-1~bpo12+1","6.12.90-1","6.12.90-1~bpo12+1","6.12.90-2","6.12.90-2~bpo12+1","6.12.94-1","6.12.94-1~bpo12+1","6.12.95-1","6.12.95-1~bpo12+1","6.12.96-1","6.13.10-1~exp1","6.13.11-1~exp1","6.13.2-1~exp1","6.13.3-1~exp1","6.13.4-1~exp1","6.13.5-1~exp1","6.13.6-1~exp1","6.13.7-1~exp1","6.13.8-1~exp1","6.13.9-1~exp1","6.13~rc6-1~exp1","6.13~rc7-1~exp1","6.14.3-1~exp1","6.14.5-1~exp1","6.14.6-1~exp1","6.15-1~exp1","6.15.1-1~exp1","6.15.2-1~exp1","6.15.3-1~exp1","6.15.4-1~exp1","6.15.5-1~exp1","6.15.6-1~exp1","6.15~rc7-1~exp1","6.16-1~exp1","6.16.1-1~exp1","6.16.10-1","6.16.11-1","6.16.12-1","6.16.12-1~bpo13+1","6.16.12-2","6.16.3-1","6.16.3-1~bpo13+1","6.16.5-1","6.16.6-1","6.16.7-1","6.16.8-1","6.16.9-1","6.16~rc7-1~exp1","6.17.2-1~exp1","6.17.5-1~exp1"],"ecosystem_specific":{"urgency":"not yet assigned"},"database_specific":{"source":"https://storage.googleapis.com/osv-test-debian-osv/debian-cve-osv/DEBIAN-CVE-2025-40147.json"}}],"schema_version":"1.9.0"}