The patch below does not apply to the 4.14-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <stable@xxxxxxxxxxxxxxx>. To reproduce the conflict and resubmit, you may use the following commands: git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-4.14.y git checkout FETCH_HEAD git cherry-pick -x 1aee9158bc978f91701c5992e395efbc6da2de3c # <resolve conflicts, build, test, etc.> git commit -s git send-email --to '<stable@xxxxxxxxxxxxxxx>' --in-reply-to '2023102703-naming-synthetic-7515@gregkh' --subject-prefix 'PATCH 4.14.y' HEAD^.. Possible dependencies: thanks, greg k-h ------------------ original commit in Linus's tree ------------------ >From 1aee9158bc978f91701c5992e395efbc6da2de3c Mon Sep 17 00:00:00 2001 From: Al Viro <viro@xxxxxxxxxxxxxxxxxx> Date: Sat, 14 Oct 2023 21:34:40 -0400 Subject: [PATCH] nfsd: lock_rename() needs both directories to live on the same fs ... checking that after lock_rename() is too late. Incidentally, NFSv2 had no nfserr_xdev... Fixes: aa387d6ce153 "nfsd: fix EXDEV checking in rename" Cc: stable@xxxxxxxxxxxxxxx # v3.9+ Reviewed-by: Jeff Layton <jlayton@xxxxxxxxxx> Acked-by: Chuck Lever <chuck.lever@xxxxxxxxxx> Tested-by: Jeff Layton <jlayton@xxxxxxxxxx> Signed-off-by: Al Viro <viro@xxxxxxxxxxxxxxxxxx> diff --git a/fs/nfsd/vfs.c b/fs/nfsd/vfs.c index 48260cf68fde..02f5fcaad03f 100644 --- a/fs/nfsd/vfs.c +++ b/fs/nfsd/vfs.c @@ -1788,6 +1788,12 @@ nfsd_rename(struct svc_rqst *rqstp, struct svc_fh *ffhp, char *fname, int flen, if (!flen || isdotent(fname, flen) || !tlen || isdotent(tname, tlen)) goto out; + err = (rqstp->rq_vers == 2) ? nfserr_acces : nfserr_xdev; + if (ffhp->fh_export->ex_path.mnt != tfhp->fh_export->ex_path.mnt) + goto out; + if (ffhp->fh_export->ex_path.dentry != tfhp->fh_export->ex_path.dentry) + goto out; + retry: host_err = fh_want_write(ffhp); if (host_err) { @@ -1823,12 +1829,6 @@ nfsd_rename(struct svc_rqst *rqstp, struct svc_fh *ffhp, char *fname, int flen, if (ndentry == trap) goto out_dput_new; - host_err = -EXDEV; - if (ffhp->fh_export->ex_path.mnt != tfhp->fh_export->ex_path.mnt) - goto out_dput_new; - if (ffhp->fh_export->ex_path.dentry != tfhp->fh_export->ex_path.dentry) - goto out_dput_new; - if ((ndentry->d_sb->s_export_op->flags & EXPORT_OP_CLOSE_BEFORE_UNLINK) && nfsd_has_cached_files(ndentry)) { close_cached = true;
