nfsd4: fix file leak on open_downgrade

Stateid's hold a read reference for a read open, a write reference for a
write open, and an additional one of each for each read+write open.  The
latter wasn't getting put on a downgrade, so something like:

	open RW
	open R
	downgrade to R

was resulting in a file leak.

Also fix an imbalance in an error path.

Regression from 7d94784293 "nfsd4: fix
downgrade/lock logic".

Cc: stable@kernel.org
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
This commit is contained in:
J. Bruce Fields 2011-06-29 08:23:50 -04:00
parent 499f3edc23
commit f197c27196

View File

@ -2336,15 +2336,6 @@ nfs4_share_conflict(struct svc_fh *current_fh, unsigned int deny_type)
return ret;
}
static inline void
nfs4_file_downgrade(struct nfs4_file *fp, unsigned int share_access)
{
if (share_access & NFS4_SHARE_ACCESS_WRITE)
nfs4_file_put_access(fp, O_WRONLY);
if (share_access & NFS4_SHARE_ACCESS_READ)
nfs4_file_put_access(fp, O_RDONLY);
}
static void nfsd_break_one_deleg(struct nfs4_delegation *dp)
{
/* We're assuming the state code never drops its reference
@ -2625,7 +2616,7 @@ nfs4_upgrade_open(struct svc_rqst *rqstp, struct nfs4_file *fp, struct svc_fh *c
status = nfsd4_truncate(rqstp, cur_fh, open);
if (status) {
if (new_access) {
int oflag = nfs4_access_to_omode(new_access);
int oflag = nfs4_access_to_omode(op_share_access);
nfs4_file_put_access(fp, oflag);
}
return status;
@ -3489,18 +3480,15 @@ nfsd4_open_confirm(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
return status;
}
/*
* unset all bits in union bitmap (bmap) that
* do not exist in share (from successful OPEN_DOWNGRADE)
*/
static void
reset_union_bmap_access(unsigned long access, unsigned long *bmap)
static inline void nfs4_file_downgrade(struct nfs4_stateid *stp, unsigned int to_access)
{
int i;
for (i = 1; i < 4; i++) {
if ((i & access) != i)
__clear_bit(i, bmap);
if (test_bit(i, &stp->st_access_bmap) && !(i & to_access)) {
nfs4_file_put_access(stp->st_file, i);
__clear_bit(i, &stp->st_access_bmap);
}
}
}
@ -3521,7 +3509,6 @@ nfsd4_open_downgrade(struct svc_rqst *rqstp,
{
__be32 status;
struct nfs4_stateid *stp;
unsigned int share_access;
dprintk("NFSD: nfsd4_open_downgrade on file %.*s\n",
(int)cstate->current_fh.fh_dentry->d_name.len,
@ -3550,10 +3537,8 @@ nfsd4_open_downgrade(struct svc_rqst *rqstp,
stp->st_deny_bmap, od->od_share_deny);
goto out;
}
set_access(&share_access, stp->st_access_bmap);
nfs4_file_downgrade(stp->st_file, share_access & ~od->od_share_access);
nfs4_file_downgrade(stp, od->od_share_access);
reset_union_bmap_access(od->od_share_access, &stp->st_access_bmap);
reset_union_bmap_deny(od->od_share_deny, &stp->st_deny_bmap);
update_stateid(&stp->st_stateid);