diff options
| author | Al Viro <viro@zeniv.linux.org.uk> | 2025-09-16 17:22:45 +0100 |
|---|---|---|
| committer | Anna Schumaker <anna.schumaker@oracle.com> | 2025-09-23 13:29:51 -0400 |
| commit | a890a2e339b929dbd843328f9a92a1625404fe63 (patch) | |
| tree | ba456d5250043c1abda3482b15da328788e396b9 | |
| parent | 902893e3907620153a17fb40834ab6fba9f83fab (diff) | |
nfs4_setup_readdir(): insufficient locking for ->d_parent->d_inode dereferencing
Theoretically it's an oopsable race, but I don't believe one can manage
to hit it on real hardware; might become doable on a KVM, but it still
won't be easy to attack.
Anyway, it's easy to deal with - since xdr_encode_hyper() is just a call of
put_unaligned_be64(), we can put that under ->d_lock and be done with that.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Anna Schumaker <anna.schumaker@oracle.com>
| -rw-r--r-- | fs/nfs/nfs4proc.c | 2 |
1 files changed, 2 insertions, 0 deletions
diff --git a/fs/nfs/nfs4proc.c b/fs/nfs/nfs4proc.c index a5085820ec0a..f58098417142 100644 --- a/fs/nfs/nfs4proc.c +++ b/fs/nfs/nfs4proc.c @@ -391,7 +391,9 @@ static void nfs4_setup_readdir(u64 cookie, __be32 *verifier, struct dentry *dent *p++ = htonl(attrs); /* bitmap */ *p++ = htonl(12); /* attribute buffer length */ *p++ = htonl(NF4DIR); + spin_lock(&dentry->d_lock); p = xdr_encode_hyper(p, NFS_FILEID(d_inode(dentry->d_parent))); + spin_unlock(&dentry->d_lock); readdir->pgbase = (char *)p - (char *)start; readdir->count -= readdir->pgbase; |