| Message ID | 1427122424-8078-2-git-send-email-jeff.layton@primarydata.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c index d2f2c37dc2db..cf29d1a698b3 100644 --- a/fs/nfsd/nfs4state.c +++ b/fs/nfsd/nfs4state.c @@ -3221,7 +3221,7 @@ alloc_init_open_stateowner(unsigned int strhashval, struct nfsd4_open *open, } else nfs4_free_openowner(&oo->oo_owner); spin_unlock(&clp->cl_lock); - return oo; + return ret; } static void init_open_stateid(struct nfs4_ol_stateid *stp, struct nfs4_file *fp, struct nfsd4_open *open) {
alloc_init_open_stateowner can return an already freed entry if there is a race to put openowners in the hashtable. In commit 7ffb588086e9, we changed it so that we allocate and initialize an openowner, and then check to see if a matching one got stuffed into the hashtable in the meantime. If it did, then we free the one we just allocated and take a reference on the one already there. There is a bug here though. The code will then return the pointer to the one that was allocated (and has now been freed). This wasn't evident before as this race almost never occurred. The Linux kernel client used to serialize requests for a single openowner. That has changed now with v4.0 kernels, and this race can now easily occur. Fixes: 7ffb588086e9 Cc: <stable@vger.kernel.org> # v3.17+ Cc: Trond Myklebust <trond.myklebust@primarydata.com> Reported-by: Christoph Hellwig <hch@infradead.org> Signed-off-by: Jeff Layton <jeff.layton@primarydata.com> --- fs/nfsd/nfs4state.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)