nfsd4: check for uninitialized slot
This fixes an oops when a buggy client tries to use an initial seqid of
0 on a new slot, which we may misinterpret as a replay.
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c
index e0e706f..2387791 100644
--- a/fs/nfsd/nfs4state.c
+++ b/fs/nfsd/nfs4state.c
@@ -1347,6 +1347,7 @@
slot->sl_opcnt = resp->opcnt;
slot->sl_status = resp->cstate.status;
+ slot->sl_flags |= NFSD4_SLOT_INITIALIZED;
if (nfsd4_not_cached(resp)) {
slot->sl_datalen = 0;
return;
@@ -1916,6 +1917,9 @@
status = check_slot_seqid(seq->seqid, slot->sl_seqid,
slot->sl_flags & NFSD4_SLOT_INUSE);
if (status == nfserr_replay_cache) {
+ status = nfserr_seq_misordered;
+ if (!(slot->sl_flags & NFSD4_SLOT_INITIALIZED))
+ goto out;
cstate->slot = slot;
cstate->session = session;
/* Return the cached reply status and set cstate->status
@@ -1932,9 +1936,11 @@
/* Success! bump slot seqid */
slot->sl_seqid = seq->seqid;
- slot->sl_flags = NFSD4_SLOT_INUSE;
+ slot->sl_flags |= NFSD4_SLOT_INUSE;
if (seq->cachethis)
slot->sl_flags |= NFSD4_SLOT_CACHETHIS;
+ else
+ slot->sl_flags &= ~NFSD4_SLOT_CACHETHIS;
cstate->slot = slot;
cstate->session = session;
diff --git a/fs/nfsd/state.h b/fs/nfsd/state.h
index 122217f..d8f52a0 100644
--- a/fs/nfsd/state.h
+++ b/fs/nfsd/state.h
@@ -134,6 +134,7 @@
u16 sl_opcnt;
#define NFSD4_SLOT_INUSE (1 << 0)
#define NFSD4_SLOT_CACHETHIS (1 << 1)
+#define NFSD4_SLOT_INITIALIZED (1 << 2)
u8 sl_flags;
char sl_data[];
};