[PATCH 002 of 5] knfsd: nfsd4: fix open permission checking

From: NeilBrown
Date: Mon Oct 16 2006 - 19:31:49 EST



From: "J. Bruce Fields" <bfields@xxxxxxxxxxxx>
We weren't actually checking for SHARE_ACCESS_WRITE, with the result that
the owner could open a non-writeable file for write!

Continue to allow DENY_WRITE only with write access.

Thanks to Jim Rees for reporting the bug.

Signed-off-by: J. Bruce Fields <bfields@xxxxxxxxxxxxxx>
Signed-off-by: Neil Brown <neilb@xxxxxxx>

### Diffstat output
./fs/nfsd/nfs4proc.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)

diff .prev/fs/nfsd/nfs4proc.c ./fs/nfsd/nfs4proc.c
--- .prev/fs/nfsd/nfs4proc.c 2006-10-17 09:02:26.000000000 +1000
+++ ./fs/nfsd/nfs4proc.c 2006-10-17 09:04:13.000000000 +1000
@@ -78,8 +78,10 @@ do_open_permission(struct svc_rqst *rqst

if (open->op_share_access & NFS4_SHARE_ACCESS_READ)
accmode |= MAY_READ;
- if (open->op_share_deny & NFS4_SHARE_ACCESS_WRITE)
+ if (open->op_share_access & NFS4_SHARE_ACCESS_WRITE)
accmode |= (MAY_WRITE | MAY_TRUNC);
+ if (open->op_share_deny & NFS4_SHARE_DENY_WRITE)
+ accmode |= MAY_WRITE;

status = fh_verify(rqstp, current_fh, S_IFREG, accmode);

-
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