openkylin
/
linux
mirror of https://gitee.com/openkylin/linux.git
9
0
Fork 0
Code Issues Projects Releases Wiki Activity

nfsd: Make creates return EEXIST instead of EACCES 

When doing a create (mkdir/mknod) on a name, it's worth
checking the name exists first before returning EACCES in case
the directory is not writeable by the user.
This makes return values on the client more consistent
regardless of whenever the entry there is cached in the local
cache or not.
Another positive side effect is certain programs only expect
EEXIST in that case even despite POSIX allowing any valid
error to be returned.

Signed-off-by: Oleg Drokin <green@linuxhacker.ru>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
This commit is contained in:
Oleg Drokin 2016-07-14 23:20:22 -04:00 committed by J. Bruce Fields
parent c7995f8a70
commit 7eed34f18d
2 changed files with 15 additions and 2 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

6
fs/nfsd/nfs4proc.c
View File

@ -605,8 +605,12 @@ nfsd4_create(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
fh_init(&resfh, NFS4_FHSIZE);
/*
* We just check that parent is accessible here, nfsd_* do their
* own access permission checks
*/
status = fh_verify(rqstp, &cstate->current_fh, S_IFDIR,
NFSD_MAY_CREATE);
NFSD_MAY_EXEC);
if (status)
return status;

11
fs/nfsd/vfs.c
View File

@ -1161,7 +1161,11 @@ nfsd_create(struct svc_rqst *rqstp, struct svc_fh *fhp,
if (isdotent(fname, flen))
goto out;
err = fh_verify(rqstp, fhp, S_IFDIR, NFSD_MAY_CREATE);
/*
* Even though it is a create, first let's see if we are even allowed
* to peek inside the parent
*/
err = fh_verify(rqstp, fhp, S_IFDIR, NFSD_MAY_EXEC);
if (err)
goto out;
@ -1211,6 +1215,11 @@ nfsd_create(struct svc_rqst *rqstp, struct svc_fh *fhp,
goto out;
}
/* Now let's see if we actually have permissions to create */
err = nfsd_permission(rqstp, fhp->fh_export, dentry, NFSD_MAY_CREATE);
if (err)
goto out;
if (!(iap->ia_valid & ATTR_MODE))
iap->ia_mode = 0;
iap->ia_mode = (iap->ia_mode & S_IALLUGO) | type;