UbiquitousOS
/
OpenCloudOS-Kernel
mirror of https://gitee.com/OpenCloudOS/OpenCloudOS-Kernel.git
11
0
Fork 0
Code Issues Projects Releases Wiki Activity

nfsd: notify_change needs elevated write count 

Looks like this bug has been here since these write counts were
introduced, not sure why it was just noticed now.

Thanks also to Jan Kara for pointing out the problem.

Cc: stable@vger.kernel.org
Reported-by: Matthew Rahtz <mrahtz@rapitasystems.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
This commit is contained in:
J. Bruce Fields 2014-02-24 14:59:47 -05:00
parent a11fcce154
commit 9f67f18993
1 changed files with 9 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

9
fs/nfsd/vfs.c
View File

@ -404,6 +404,7 @@ nfsd_setattr(struct svc_rqst *rqstp, struct svc_fh *fhp, struct iattr *iap,
umode_t ftype = 0; umode_t ftype = 0;
__be32 err; __be32 err;
int host_err; int host_err;
bool get_write_count;
int size_change = 0; int size_change = 0;
if (iap->ia_valid & (ATTR_ATIME | ATTR_MTIME | ATTR_SIZE)) if (iap->ia_valid & (ATTR_ATIME | ATTR_MTIME | ATTR_SIZE))
@ -411,10 +412,18 @@ nfsd_setattr(struct svc_rqst *rqstp, struct svc_fh *fhp, struct iattr *iap,
if (iap->ia_valid & ATTR_SIZE) if (iap->ia_valid & ATTR_SIZE)
ftype = S_IFREG; ftype = S_IFREG;
/* Callers that do fh_verify should do the fh_want_write: */
get_write_count = !fhp->fh_dentry;
/* Get inode */ /* Get inode */
err = fh_verify(rqstp, fhp, ftype, accmode); err = fh_verify(rqstp, fhp, ftype, accmode);
if (err) if (err)
goto out; goto out;
if (get_write_count) {
host_err = fh_want_write(fhp);
if (host_err)
return nfserrno(host_err);
}
dentry = fhp->fh_dentry; dentry = fhp->fh_dentry;
inode = dentry->d_inode; inode = dentry->d_inode;