nfsd: don't fail unchecked creates of non-special files
authorJ. Bruce Fields <bfields@redhat.com>
Mon, 9 Apr 2012 22:06:49 +0000 (18:06 -0400)
committerJ. Bruce Fields <bfields@redhat.com>
Wed, 11 Apr 2012 21:49:52 +0000 (17:49 -0400)
commit9dc4e6c4d1182d34604ea40fef641775f5b15456
tree22b055349ea646026a97ea0b0cc7da32c18f26dd
parent0034102808e0dbbf3a2394b82b1bb40b5778de9e
nfsd: don't fail unchecked creates of non-special files

Allow a v3 unchecked open of a non-regular file succeed as if it were a
lookup; typically a client in such a case will want to fall back on a
local open, so succeeding and giving it the filehandle is more useful
than failing with nfserr_exist, which makes it appear that nothing at
all exists by that name.

Similarly for v4, on an open-create, return the same errors we would on
an attempt to open a non-regular file, instead of returning
nfserr_exist.

This fixes a problem found doing a v4 open of a symlink with
O_RDONLY|O_CREAT, which resulted in the current client returning EEXIST.

Thanks also to Trond for analysis.

Cc: stable@kernel.org
Reported-by: Orion Poplawski <orion@cora.nwra.com>
Tested-by: Orion Poplawski <orion@cora.nwra.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
fs/nfsd/nfs4proc.c
fs/nfsd/vfs.c