diff options
| author | J. Bruce Fields <bfields@redhat.com> | 2014-03-10 17:19:10 +0100 |
|---|---|---|
| committer | J. Bruce Fields <bfields@redhat.com> | 2014-05-30 23:31:55 +0200 |
| commit | 8c7424cff6bd33459945646cfcbf6dc6c899ab24 (patch) | |
| tree | b407f5e3603364585e1116cf9300b449a262a85b /fs/nfsd | |
| parent | nfsd4: convert 4.1 replay encoding (diff) | |
| download | linux-8c7424cff6bd33459945646cfcbf6dc6c899ab24.tar.xz linux-8c7424cff6bd33459945646cfcbf6dc6c899ab24.zip | |
nfsd4: don't try to encode conflicting owner if low on space
I ran into this corner case in testing: in theory clients can provide
state owners up to 1024 bytes long. In the sessions case there might be
a risk of this pushing us over the DRC slot size.
The conflicting owner isn't really that important, so let's humor a
client that provides a small maxresponsize_cached by allowing ourselves
to return without the conflicting owner instead of outright failing the
operation.
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Diffstat (limited to 'fs/nfsd')
| -rw-r--r-- | fs/nfsd/nfs4proc.c | 3 | ||||
| -rw-r--r-- | fs/nfsd/nfs4xdr.c | 16 |
2 files changed, 15 insertions, 4 deletions
diff --git a/fs/nfsd/nfs4proc.c b/fs/nfsd/nfs4proc.c index 5d8f9158701d..20aad5a3005f 100644 --- a/fs/nfsd/nfs4proc.c +++ b/fs/nfsd/nfs4proc.c @@ -1432,7 +1432,8 @@ out: #define op_encode_change_info_maxsz (5) #define nfs4_fattr_bitmap_maxsz (4) -#define op_encode_lockowner_maxsz (1 + XDR_QUADLEN(IDMAP_NAMESZ)) +/* We'll fall back on returning no lockowner if run out of space: */ +#define op_encode_lockowner_maxsz (0) #define op_encode_lock_denied_maxsz (8 + op_encode_lockowner_maxsz) #define nfs4_owner_maxsz (1 + XDR_QUADLEN(IDMAP_NAMESZ)) diff --git a/fs/nfsd/nfs4xdr.c b/fs/nfsd/nfs4xdr.c index a90a1e86614a..2f0ea20edb23 100644 --- a/fs/nfsd/nfs4xdr.c +++ b/fs/nfsd/nfs4xdr.c @@ -2878,9 +2878,20 @@ nfsd4_encode_lock_denied(struct xdr_stream *xdr, struct nfsd4_lock_denied *ld) struct xdr_netobj *conf = &ld->ld_owner; __be32 *p; +again: p = xdr_reserve_space(xdr, 32 + XDR_LEN(conf->len)); - if (!p) + if (!p) { + /* + * Don't fail to return the result just because we can't + * return the conflicting open: + */ + if (conf->len) { + conf->len = 0; + conf->data = NULL; + goto again; + } return nfserr_resource; + } WRITE64(ld->ld_start); WRITE64(ld->ld_length); WRITE32(ld->ld_type); @@ -2888,7 +2899,6 @@ nfsd4_encode_lock_denied(struct xdr_stream *xdr, struct nfsd4_lock_denied *ld) WRITEMEM(&ld->ld_clientid, 8); WRITE32(conf->len); WRITEMEM(conf->data, conf->len); - kfree(conf->data); } else { /* non - nfsv4 lock in conflict, no clientid nor owner */ WRITE64((u64)0); /* clientid */ WRITE32(0); /* length of owner name */ @@ -2905,7 +2915,7 @@ nfsd4_encode_lock(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_lo nfserr = nfsd4_encode_stateid(xdr, &lock->lk_resp_stateid); else if (nfserr == nfserr_denied) nfserr = nfsd4_encode_lock_denied(xdr, &lock->lk_denied); - + kfree(lock->lk_denied.ld_owner.data); return nfserr; } |