stable inclusion from stable-v6.6.95 commit 5060e1a5fef184bd11d298e3f0ee920d96a23236 category: bugfix bugzilla: https://gitee.com/src-openeuler/kernel/issues/ICK4NH CVE: CVE-2025-38231 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=... -------------------------------- commit b31da62889e6d610114d81dc7a6edbcaa503fcf8 upstream. In nfs4_state_start_net(), laundromat_work may access nfsd_ssc through nfs4_laundromat -> nfsd4_ssc_expire_umount. If nfsd_ssc isn't initialized, this can cause NULL pointer dereference. Normally the delayed start of laundromat_work allows sufficient time for nfsd_ssc initialization to complete. However, when the kernel waits too long for userspace responses (e.g. in nfs4_state_start_net -> nfsd4_end_grace -> nfsd4_record_grace_done -> nfsd4_cld_grace_done -> cld_pipe_upcall -> __cld_pipe_upcall -> wait_for_completion path), the delayed work may start before nfsd_ssc initialization finishes. Fix this by moving nfsd_ssc initialization before starting laundromat_work. Fixes: f4e44b393389 ("NFSD: delay unmount source's export after inter-server copy completed.") Cc: stable@vger.kernel.org Reviewed-by: Jeff Layton <jlayton@kernel.org> Signed-off-by: Li Lingfeng <lilingfeng3@huawei.com> Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Li Lingfeng <lilingfeng3@huawei.com> --- fs/nfsd/nfssvc.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/fs/nfsd/nfssvc.c b/fs/nfsd/nfssvc.c index 710a54c7dffc..623f522b1565 100644 --- a/fs/nfsd/nfssvc.c +++ b/fs/nfsd/nfssvc.c @@ -432,13 +432,13 @@ static int nfsd_startup_net(struct net *net, const struct cred *cred) if (ret) goto out_filecache; +#ifdef CONFIG_NFSD_V4_2_INTER_SSC + nfsd4_ssc_init_umount_work(nn); +#endif ret = nfs4_state_start_net(net); if (ret) goto out_reply_cache; -#ifdef CONFIG_NFSD_V4_2_INTER_SSC - nfsd4_ssc_init_umount_work(nn); -#endif nn->nfsd_net_up = true; return 0; -- 2.46.1