{"id":"CVE-2025-39866","revision":"ae77d0ad2b454a45a93b6a27cfacf5fe","records":[{"revision":"ae77d0ad2b454a45a93b6a27cfacf5fe","observedAt":"2026-10-23T15:48:27.903+00:00","statement":{"source":"cve-program","id":"CVE-2025-39866","aliases":[],"title":"fs: writeback: fix use-after-free in __mark_inode_dirty()","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nfs: writeback: fix use-after-free in __mark_inode_dirty()\n\nAn use-after-free issue occurred when __mark_inode_dirty() get the\nbdi_writeback that was in the progress of switching.\n\nCPU: 1 PID: 562 Comm: systemd-random- Not tainted 6.6.56-gb4403bd46a8e #1\n......\npstate: 60400005 (nZCv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--)\npc : __mark_inode_dirty+0x124/0x418\nlr : __mark_inode_dirty+0x118/0x418\nsp : ffffffc08c9dbbc0\n........\nCall trace:\n __mark_inode_dirty+0x124/0x418\n generic_update_time+0x4c/0x60\n file_modified+0xcc/0xd0\n ext4_buffered_write_iter+0x58/0x124\n ext4_file_write_iter+0x54/0x704\n vfs_write+0x1c0/0x308\n ksys_write+0x74/0x10c\n __arm64_sys_write+0x1c/0x28\n invoke_syscall+0x48/0x114\n el0_svc_common.constprop.0+0xc0/0xe0\n do_el0_svc+0x1c/0x28\n el0_svc+0x40/0xe4\n el0t_64_sync_handler+0x120/0x12c\n el0t_64_sync+0x194/0x198\n\nRoot cause is:\n\nsystemd-random-seed                         kworker\n----------------------------------------------------------------------\n___mark_inode_dirty                     inode_switch_wbs_work_fn\n\n  spin_lock(&inode->i_lock);\n  inode_attach_wb\n  locked_inode_to_wb_and_lock_list\n     get inode->i_wb\n     spin_unlock(&inode->i_lock);\n     spin_lock(&wb->list_lock)\n  spin_lock(&inode->i_lock)\n  inode_io_list_move_locked\n  spin_unlock(&wb->list_lock)\n  spin_unlock(&inode->i_lock)\n                                    spin_lock(&old_wb->list_lock)\n                                      inode_do_switch_wbs\n                                        spin_lock(&inode->i_lock)\n                                        inode->i_wb = new_wb\n                                        spin_unlock(&inode->i_lock)\n                                    spin_unlock(&old_wb->list_lock)\n                                    wb_put_many(old_wb, nr_switched)\n                                      cgwb_release\n                                      old wb released\n  wb_wakeup_delayed() accesses wb,\n  then trigger the use-after-free\n  issue\n\nFix this race condition by holding inode spinlock until\nwb_wakeup_delayed() finished.","state":0,"publishedAt":"2025-09-19T15:26:35.725+00:00","modifiedAt":"2026-10-15T22:02:32.619+00:00","affected":[{"ecosystem":"Vendor product","name":"Linux","ranges":[],"versions":[],"rawVersionEvidence":"{\n                    \"product\": \"Linux\",\n                    \"vendor\": \"Linux\",\n                    \"defaultStatus\": \"unaffected\",\n                    \"repo\": \"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git\",\n                    \"programFiles\": [\n                        \"fs/fs-writeback.c\"\n                    ],\n                    \"versions\": [\n                        {\n                            \"version\": \"0747259d13febfcc838980a63c414c9b920cea6f\",\n                            \"lessThan\": \"e2a14bbae5d8bacaa301362744a110e2be40a3a3\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"0747259d13febfcc838980a63c414c9b920cea6f\",\n                            \"lessThan\": \"b187c976111960e6e54a6b1fff724f6e3d39406c\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"0747259d13febfcc838980a63c414c9b920cea6f\",\n                            \"lessThan\": \"1edc2feb9c759a9883dfe81cb5ed231412d8b2e4\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"0747259d13febfcc838980a63c414c9b920cea6f\",\n                            \"lessThan\": \"bf89b1f87c72df79cf76203f71fbf8349cd5c9de\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"0747259d13febfcc838980a63c414c9b920cea6f\",\n                            \"lessThan\": \"e63052921f1b25a836feb1500b841bff7a4a0456\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"0747259d13febfcc838980a63c414c9b920cea6f\",\n                            \"lessThan\": \"c8c14adf80bd1a6e4a1d7ee9c2a816881c26d17a\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"0747259d13febfcc838980a63c414c9b920cea6f\",\n                            \"lessThan\": \"d02d2c98d25793902f65803ab853b592c7a96b29\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        }\n                    ]\n                }"},{"ecosystem":"Vendor product","name":"Linux","ranges":[],"versions":[],"rawVersionEvidence":"{\n                    \"product\": \"Linux\",\n                    \"vendor\": \"Linux\",\n                    \"defaultStatus\": \"affected\",\n                    \"repo\": \"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git\",\n                    \"programFiles\": [\n                        \"fs/fs-writeback.c\"\n                    ],\n                    \"versions\": [\n                        {\n                            \"version\": \"4.2\",\n                            \"status\": \"affected\"\n                        },\n                        {\n                            \"version\": \"0\",\n                            \"lessThan\": \"4.2\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"5.10.247\",\n                            \"lessThanOrEqual\": \"5.10.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"5.15.192\",\n                            \"lessThanOrEqual\": \"5.15.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"6.1.151\",\n                            \"lessThanOrEqual\": \"6.1.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"6.6.105\",\n                            \"lessThanOrEqual\": \"6.6.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"6.12.46\",\n                            \"lessThanOrEqual\": \"6.12.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"6.16.6\",\n                            \"lessThanOrEqual\": \"6.16.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"6.17\",\n                            \"lessThanOrEqual\": \"*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"original_commit_for_fix\"\n                        }\n                    ]\n                }"}],"metrics":[{"system":"CVSS 3.1","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","score":7.8,"severity":"HIGH"}],"references":["https://git.kernel.org/stable/c/e2a14bbae5d8bacaa301362744a110e2be40a3a3","https://git.kernel.org/stable/c/b187c976111960e6e54a6b1fff724f6e3d39406c","https://git.kernel.org/stable/c/1edc2feb9c759a9883dfe81cb5ed231412d8b2e4","https://git.kernel.org/stable/c/bf89b1f87c72df79cf76203f71fbf8349cd5c9de","https://git.kernel.org/stable/c/e63052921f1b25a836feb1500b841bff7a4a0456","https://git.kernel.org/stable/c/c8c14adf80bd1a6e4a1d7ee9c2a816881c26d17a","https://git.kernel.org/stable/c/d02d2c98d25793902f65803ab853b592c7a96b29"],"sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2025-39866","license":"CVE Program Terms of Use","key":"cve-program:CVE-2025-39866","identifiers":["CVE-2025-39866"]},"retained":false,"historicalAffected":[]}],"coverage":[]}