From 44ea8dfce021db1db6a31970b1f13a80366a1f21 Mon Sep 17 00:00:00 2001 From: Trond Myklebust Date: Thu, 2 Apr 2020 15:37:02 -0400 Subject: [PATCH] NFS/pnfs: Reference the layout cred in pnfs_prepare_layoutreturn() When we're sending a layoutreturn, ensure that we reference the layout cred atomically with the copy of the stateid. Signed-off-by: Trond Myklebust --- fs/nfs/nfs4proc.c | 1 + fs/nfs/pnfs.c | 52 +++++++++++++++++++++++++++++++++------------------- 2 files changed, 34 insertions(+), 19 deletions(-) diff --git a/fs/nfs/nfs4proc.c b/fs/nfs/nfs4proc.c index e4f8311..99e9f2e 100644 --- a/fs/nfs/nfs4proc.c +++ b/fs/nfs/nfs4proc.c @@ -9297,6 +9297,7 @@ static void nfs4_layoutreturn_release(void *calldata) lrp->ld_private.ops->free(&lrp->ld_private); pnfs_put_layout_hdr(lrp->args.layout); nfs_iput_and_deactive(lrp->inode); + put_cred(lrp->cred); kfree(calldata); dprintk("<-- %s\n", __func__); } diff --git a/fs/nfs/pnfs.c b/fs/nfs/pnfs.c index 84029c9b..f2dc35c 100644 --- a/fs/nfs/pnfs.c +++ b/fs/nfs/pnfs.c @@ -1144,6 +1144,7 @@ out_unlock: static bool pnfs_prepare_layoutreturn(struct pnfs_layout_hdr *lo, nfs4_stateid *stateid, + const struct cred **cred, enum pnfs_iomode *iomode) { /* Serialise LAYOUTGET/LAYOUTRETURN */ @@ -1154,18 +1155,17 @@ pnfs_prepare_layoutreturn(struct pnfs_layout_hdr *lo, set_bit(NFS_LAYOUT_RETURN, &lo->plh_flags); pnfs_get_layout_hdr(lo); if (test_bit(NFS_LAYOUT_RETURN_REQUESTED, &lo->plh_flags)) { - if (stateid != NULL) { - nfs4_stateid_copy(stateid, &lo->plh_stateid); - if (lo->plh_return_seq != 0) - stateid->seqid = cpu_to_be32(lo->plh_return_seq); - } + nfs4_stateid_copy(stateid, &lo->plh_stateid); + *cred = get_cred(lo->plh_lc_cred); + if (lo->plh_return_seq != 0) + stateid->seqid = cpu_to_be32(lo->plh_return_seq); if (iomode != NULL) *iomode = lo->plh_return_iomode; pnfs_clear_layoutreturn_info(lo); return true; } - if (stateid != NULL) - nfs4_stateid_copy(stateid, &lo->plh_stateid); + nfs4_stateid_copy(stateid, &lo->plh_stateid); + *cred = get_cred(lo->plh_lc_cred); if (iomode != NULL) *iomode = IOMODE_ANY; return true; @@ -1189,20 +1189,26 @@ pnfs_init_layoutreturn_args(struct nfs4_layoutreturn_args *args, } static int -pnfs_send_layoutreturn(struct pnfs_layout_hdr *lo, const nfs4_stateid *stateid, - enum pnfs_iomode iomode, bool sync) +pnfs_send_layoutreturn(struct pnfs_layout_hdr *lo, + const nfs4_stateid *stateid, + const struct cred **pcred, + enum pnfs_iomode iomode, + bool sync) { struct inode *ino = lo->plh_inode; struct pnfs_layoutdriver_type *ld = NFS_SERVER(ino)->pnfs_curr_ld; struct nfs4_layoutreturn *lrp; + const struct cred *cred = *pcred; int status = 0; + *pcred = NULL; lrp = kzalloc(sizeof(*lrp), GFP_NOFS); if (unlikely(lrp == NULL)) { status = -ENOMEM; spin_lock(&ino->i_lock); pnfs_clear_layoutreturn_waitbit(lo); spin_unlock(&ino->i_lock); + put_cred(cred); pnfs_put_layout_hdr(lo); goto out; } @@ -1210,7 +1216,7 @@ pnfs_send_layoutreturn(struct pnfs_layout_hdr *lo, const nfs4_stateid *stateid, pnfs_init_layoutreturn_args(&lrp->args, lo, stateid, iomode); lrp->args.ld_private = &lrp->ld_private; lrp->clp = NFS_SERVER(ino)->nfs_client; - lrp->cred = lo->plh_lc_cred; + lrp->cred = cred; if (ld->prepare_layoutreturn) ld->prepare_layoutreturn(&lrp->args); @@ -1255,15 +1261,16 @@ static void pnfs_layoutreturn_before_put_layout_hdr(struct pnfs_layout_hdr *lo) return; spin_lock(&inode->i_lock); if (pnfs_layout_need_return(lo)) { + const struct cred *cred; nfs4_stateid stateid; enum pnfs_iomode iomode; bool send; - send = pnfs_prepare_layoutreturn(lo, &stateid, &iomode); + send = pnfs_prepare_layoutreturn(lo, &stateid, &cred, &iomode); spin_unlock(&inode->i_lock); if (send) { /* Send an async layoutreturn so we dont deadlock */ - pnfs_send_layoutreturn(lo, &stateid, iomode, false); + pnfs_send_layoutreturn(lo, &stateid, &cred, iomode, false); } } else spin_unlock(&inode->i_lock); @@ -1283,6 +1290,7 @@ _pnfs_return_layout(struct inode *ino) struct pnfs_layout_hdr *lo = NULL; struct nfs_inode *nfsi = NFS_I(ino); LIST_HEAD(tmp_list); + const struct cred *cred; nfs4_stateid stateid; int status = 0; bool send, valid_layout; @@ -1327,10 +1335,10 @@ _pnfs_return_layout(struct inode *ino) goto out_put_layout_hdr; } - send = pnfs_prepare_layoutreturn(lo, &stateid, NULL); + send = pnfs_prepare_layoutreturn(lo, &stateid, &cred, NULL); spin_unlock(&ino->i_lock); if (send) - status = pnfs_send_layoutreturn(lo, &stateid, IOMODE_ANY, true); + status = pnfs_send_layoutreturn(lo, &stateid, &cred, IOMODE_ANY, true); out_put_layout_hdr: pnfs_free_lseg_list(&tmp_list); pnfs_put_layout_hdr(lo); @@ -1376,6 +1384,7 @@ bool pnfs_roc(struct inode *ino, struct nfs4_state *state; struct pnfs_layout_hdr *lo; struct pnfs_layout_segment *lseg, *next; + const struct cred *lc_cred; nfs4_stateid stateid; enum pnfs_iomode iomode = 0; bool layoutreturn = false, roc = false; @@ -1445,16 +1454,20 @@ retry: * 2. we don't send layoutreturn */ /* lo ref dropped in pnfs_roc_release() */ - layoutreturn = pnfs_prepare_layoutreturn(lo, &stateid, &iomode); + layoutreturn = pnfs_prepare_layoutreturn(lo, &stateid, &lc_cred, &iomode); /* If the creds don't match, we can't compound the layoutreturn */ - if (!layoutreturn || cred_fscmp(cred, lo->plh_lc_cred) != 0) + if (!layoutreturn) goto out_noroc; + if (cred_fscmp(cred, lc_cred) != 0) + goto out_noroc_put_cred; roc = layoutreturn; pnfs_init_layoutreturn_args(args, lo, &stateid, iomode); res->lrs_present = 0; layoutreturn = false; +out_noroc_put_cred: + put_cred(lc_cred); out_noroc: spin_unlock(&ino->i_lock); rcu_read_unlock(); @@ -1467,7 +1480,7 @@ out_noroc: return true; } if (layoutreturn) - pnfs_send_layoutreturn(lo, &stateid, iomode, true); + pnfs_send_layoutreturn(lo, &stateid, &lc_cred, iomode, true); pnfs_put_layout_hdr(lo); return false; } @@ -2464,13 +2477,14 @@ pnfs_mark_layout_for_return(struct inode *inode, * for how it works. */ if (pnfs_mark_matching_lsegs_return(lo, &lo->plh_return_segs, range, 0) != -EBUSY) { + const struct cred *cred; nfs4_stateid stateid; enum pnfs_iomode iomode; - return_now = pnfs_prepare_layoutreturn(lo, &stateid, &iomode); + return_now = pnfs_prepare_layoutreturn(lo, &stateid, &cred, &iomode); spin_unlock(&inode->i_lock); if (return_now) - pnfs_send_layoutreturn(lo, &stateid, iomode, false); + pnfs_send_layoutreturn(lo, &stateid, &cred, iomode, false); } else { spin_unlock(&inode->i_lock); nfs_commit_inode(inode, 0); -- 2.7.4