NFS: Initialise verifiers for visible dentries in readdir and lookup

[ Upstream commit 9bd545539b233725a3416801f7c374bff0327d6e ]

Ensure that the verifiers are initialised before calling
d_splice_alias() in both nfs_prime_dcache() and nfs_lookup().

Reported-by: Michael Stoler <michael.stoler@vastdata.com>
Fixes: a1147b8281 ("NFS: Fix up directory verifier races")
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
This commit is contained in:
Trond Myklebust
2025-11-19 08:36:16 -05:00
committed by Greg Kroah-Hartman
parent 29e8d9b274
commit 991609c4a7

View File

@@ -785,16 +785,17 @@ again:
goto out;
}
nfs_set_verifier(dentry, dir_verifier);
inode = nfs_fhget(dentry->d_sb, entry->fh, entry->fattr);
alias = d_splice_alias(inode, dentry);
d_lookup_done(dentry);
if (alias) {
if (IS_ERR(alias))
goto out;
nfs_set_verifier(alias, dir_verifier);
dput(dentry);
dentry = alias;
}
nfs_set_verifier(dentry, dir_verifier);
trace_nfs_readdir_lookup(d_inode(parent), dentry, 0);
out:
dput(dentry);
@@ -2000,13 +2001,14 @@ struct dentry *nfs_lookup(struct inode *dir, struct dentry * dentry, unsigned in
nfs_lookup_advise_force_readdirplus(dir, flags);
no_entry:
nfs_set_verifier(dentry, dir_verifier);
res = d_splice_alias(inode, dentry);
if (res != NULL) {
if (IS_ERR(res))
goto out;
nfs_set_verifier(res, dir_verifier);
dentry = res;
}
nfs_set_verifier(dentry, dir_verifier);
out:
trace_nfs_lookup_exit(dir, dentry, flags, PTR_ERR_OR_ZERO(res));
nfs_free_fattr(fattr);