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author | Trond Myklebust <trond.myklebust@primarydata.com> | 2015-08-31 01:37:59 (GMT) |
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committer | Trond Myklebust <trond.myklebust@primarydata.com> | 2015-08-31 01:45:04 (GMT) |
commit | 4a1e2feb9d246775dee0f78ed5b18826bae2b1c5 (patch) | |
tree | cdba7acff417d6d01bc9830203b64304b5eebf24 /fs/nfs | |
parent | 90816d1ddacfb5a8b783f67e2c1a1bc77dc50ff4 (diff) | |
download | linux-4a1e2feb9d246775dee0f78ed5b18826bae2b1c5.tar.xz |
NFSv4.1: Fix a protocol issue with CLOSE stateids
According to RFC5661 Section 18.2.4, CLOSE is supposed to return
the zero stateid. This means that nfs_clear_open_stateid_locked()
cannot assume that the result stateid will always match the 'other'
field of the existing open stateid when trying to determine a race
with a parallel OPEN.
Instead, we look at the argument, and check for matches.
Cc: stable@vger.kernel.org # v4.0+
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Diffstat (limited to 'fs/nfs')
-rw-r--r-- | fs/nfs/nfs4proc.c | 15 |
1 files changed, 10 insertions, 5 deletions
diff --git a/fs/nfs/nfs4proc.c b/fs/nfs/nfs4proc.c index 2923abf..366b81c 100644 --- a/fs/nfs/nfs4proc.c +++ b/fs/nfs/nfs4proc.c @@ -1231,6 +1231,7 @@ static void nfs_resync_open_stateid_locked(struct nfs4_state *state) } static void nfs_clear_open_stateid_locked(struct nfs4_state *state, + nfs4_stateid *arg_stateid, nfs4_stateid *stateid, fmode_t fmode) { clear_bit(NFS_O_RDWR_STATE, &state->flags); @@ -1249,8 +1250,9 @@ static void nfs_clear_open_stateid_locked(struct nfs4_state *state, if (stateid == NULL) return; /* Handle races with OPEN */ - if (!nfs4_stateid_match_other(stateid, &state->open_stateid) || - !nfs4_stateid_is_newer(stateid, &state->open_stateid)) { + if (!nfs4_stateid_match_other(arg_stateid, &state->open_stateid) || + (nfs4_stateid_match_other(stateid, &state->open_stateid) && + !nfs4_stateid_is_newer(stateid, &state->open_stateid))) { nfs_resync_open_stateid_locked(state); return; } @@ -1259,10 +1261,12 @@ static void nfs_clear_open_stateid_locked(struct nfs4_state *state, nfs4_stateid_copy(&state->open_stateid, stateid); } -static void nfs_clear_open_stateid(struct nfs4_state *state, nfs4_stateid *stateid, fmode_t fmode) +static void nfs_clear_open_stateid(struct nfs4_state *state, + nfs4_stateid *arg_stateid, + nfs4_stateid *stateid, fmode_t fmode) { write_seqlock(&state->seqlock); - nfs_clear_open_stateid_locked(state, stateid, fmode); + nfs_clear_open_stateid_locked(state, arg_stateid, stateid, fmode); write_sequnlock(&state->seqlock); if (test_bit(NFS_STATE_RECLAIM_NOGRACE, &state->flags)) nfs4_schedule_state_manager(state->owner->so_server->nfs_client); @@ -2707,7 +2711,8 @@ static void nfs4_close_done(struct rpc_task *task, void *data) goto out_release; } } - nfs_clear_open_stateid(state, res_stateid, calldata->arg.fmode); + nfs_clear_open_stateid(state, &calldata->arg.stateid, + res_stateid, calldata->arg.fmode); out_release: nfs_release_seqid(calldata->arg.seqid); nfs_refresh_inode(calldata->inode, calldata->res.fattr); |