ghsa-65ww-5pr7-752v
Vulnerability from github
In the Linux kernel, the following vulnerability has been resolved:
fs: writeback: fix use-after-free in __mark_inode_dirty()
An use-after-free issue occurred when __mark_inode_dirty() get the bdi_writeback that was in the progress of switching.
CPU: 1 PID: 562 Comm: systemd-random- Not tainted 6.6.56-gb4403bd46a8e #1 ...... pstate: 60400005 (nZCv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--) pc : __mark_inode_dirty+0x124/0x418 lr : __mark_inode_dirty+0x118/0x418 sp : ffffffc08c9dbbc0 ........ Call trace: __mark_inode_dirty+0x124/0x418 generic_update_time+0x4c/0x60 file_modified+0xcc/0xd0 ext4_buffered_write_iter+0x58/0x124 ext4_file_write_iter+0x54/0x704 vfs_write+0x1c0/0x308 ksys_write+0x74/0x10c __arm64_sys_write+0x1c/0x28 invoke_syscall+0x48/0x114 el0_svc_common.constprop.0+0xc0/0xe0 do_el0_svc+0x1c/0x28 el0_svc+0x40/0xe4 el0t_64_sync_handler+0x120/0x12c el0t_64_sync+0x194/0x198
Root cause is:
systemd-random-seed kworker
___mark_inode_dirty inode_switch_wbs_work_fn
spin_lock(&inode->i_lock); inode_attach_wb locked_inode_to_wb_and_lock_list get inode->i_wb spin_unlock(&inode->i_lock); spin_lock(&wb->list_lock) spin_lock(&inode->i_lock) inode_io_list_move_locked spin_unlock(&wb->list_lock) spin_unlock(&inode->i_lock) spin_lock(&old_wb->list_lock) inode_do_switch_wbs spin_lock(&inode->i_lock) inode->i_wb = new_wb spin_unlock(&inode->i_lock) spin_unlock(&old_wb->list_lock) wb_put_many(old_wb, nr_switched) cgwb_release old wb released wb_wakeup_delayed() accesses wb, then trigger the use-after-free issue
Fix this race condition by holding inode spinlock until wb_wakeup_delayed() finished.
{
"affected": [],
"aliases": [
"CVE-2025-39866"
],
"database_specific": {
"cwe_ids": [],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2025-09-19T16:15:45Z",
"severity": null
},
"details": "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(\u0026inode-\u003ei_lock);\n inode_attach_wb\n locked_inode_to_wb_and_lock_list\n get inode-\u003ei_wb\n spin_unlock(\u0026inode-\u003ei_lock);\n spin_lock(\u0026wb-\u003elist_lock)\n spin_lock(\u0026inode-\u003ei_lock)\n inode_io_list_move_locked\n spin_unlock(\u0026wb-\u003elist_lock)\n spin_unlock(\u0026inode-\u003ei_lock)\n spin_lock(\u0026old_wb-\u003elist_lock)\n inode_do_switch_wbs\n spin_lock(\u0026inode-\u003ei_lock)\n inode-\u003ei_wb = new_wb\n spin_unlock(\u0026inode-\u003ei_lock)\n spin_unlock(\u0026old_wb-\u003elist_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.",
"id": "GHSA-65ww-5pr7-752v",
"modified": "2025-09-22T21:30:18Z",
"published": "2025-09-22T21:30:18Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2025-39866"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/1edc2feb9c759a9883dfe81cb5ed231412d8b2e4"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/b187c976111960e6e54a6b1fff724f6e3d39406c"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/bf89b1f87c72df79cf76203f71fbf8349cd5c9de"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/c8c14adf80bd1a6e4a1d7ee9c2a816881c26d17a"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/d02d2c98d25793902f65803ab853b592c7a96b29"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/e63052921f1b25a836feb1500b841bff7a4a0456"
}
],
"schema_version": "1.4.0",
"severity": []
}
Sightings
| Author | Source | Type | Date |
|---|
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