Bug 2360241 (CVE-2025-22025)

Summary: CVE-2025-22025 kernel: nfsd: put dl_stid if fail to queue dl_recall
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security DevOps Team <prodsec-dev>
Status: NEW --- QA Contact:
Severity: low Docs Contact:
Priority: low    
Version: unspecifiedCC: dfreiber, drow, jburrell, vkumar
Target Milestone: ---Keywords: Security
Target Release: ---   
Hardware: All   
OS: Linux   
Whiteboard:
Fixed In Version: Doc Type: ---
Doc Text:
Story Points: ---
Clone Of: Environment:
Last Closed: Type: ---
Regression: --- Mount Type: ---
Documentation: --- CRM:
Verified Versions: Category: ---
oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
Cloudforms Team: --- Target Upstream Version:
Embargoed:

Description OSIDB Bzimport 2025-04-16 15:04:17 UTC
In the Linux kernel, the following vulnerability has been resolved:

nfsd: put dl_stid if fail to queue dl_recall

Before calling nfsd4_run_cb to queue dl_recall to the callback_wq, we
increment the reference count of dl_stid.
We expect that after the corresponding work_struct is processed, the
reference count of dl_stid will be decremented through the callback
function nfsd4_cb_recall_release.
However, if the call to nfsd4_run_cb fails, the incremented reference
count of dl_stid will not be decremented correspondingly, leading to the
following nfs4_stid leak:
unreferenced object 0xffff88812067b578 (size 344):
  comm "nfsd", pid 2761, jiffies 4295044002 (age 5541.241s)
  hex dump (first 32 bytes):
    01 00 00 00 6b 6b 6b 6b b8 02 c0 e2 81 88 ff ff  ....kkkk........
    00 6b 6b 6b 6b 6b 6b 6b 00 00 00 00 ad 4e ad de  .kkkkkkk.....N..
  backtrace:
    kmem_cache_alloc+0x4b9/0x700
    nfsd4_process_open1+0x34/0x300
    nfsd4_open+0x2d1/0x9d0
    nfsd4_proc_compound+0x7a2/0xe30
    nfsd_dispatch+0x241/0x3e0
    svc_process_common+0x5d3/0xcc0
    svc_process+0x2a3/0x320
    nfsd+0x180/0x2e0
    kthread+0x199/0x1d0
    ret_from_fork+0x30/0x50
    ret_from_fork_asm+0x1b/0x30
unreferenced object 0xffff8881499f4d28 (size 368):
  comm "nfsd", pid 2761, jiffies 4295044005 (age 5541.239s)
  hex dump (first 32 bytes):
    01 00 00 00 00 00 00 00 30 4d 9f 49 81 88 ff ff  ........0M.I....
    30 4d 9f 49 81 88 ff ff 20 00 00 00 01 00 00 00  0M.I.... .......
  backtrace:
    kmem_cache_alloc+0x4b9/0x700
    nfs4_alloc_stid+0x29/0x210
    alloc_init_deleg+0x92/0x2e0
    nfs4_set_delegation+0x284/0xc00
    nfs4_open_delegation+0x216/0x3f0
    nfsd4_process_open2+0x2b3/0xee0
    nfsd4_open+0x770/0x9d0
    nfsd4_proc_compound+0x7a2/0xe30
    nfsd_dispatch+0x241/0x3e0
    svc_process_common+0x5d3/0xcc0
    svc_process+0x2a3/0x320
    nfsd+0x180/0x2e0
    kthread+0x199/0x1d0
    ret_from_fork+0x30/0x50
    ret_from_fork_asm+0x1b/0x30
Fix it by checking the result of nfsd4_run_cb and call nfs4_put_stid if
fail to queue dl_recall.

Comment 1 Avinash Hanwate 2025-04-17 11:16:47 UTC
Upstream advisory:
https://lore.kernel.org/linux-cve-announce/2025041654-CVE-2025-22025-41c4@gregkh/T