On Sat, Mar 28, 2015 at 11:46:35PM +0800, Kinglong Mee wrote: > There are four macro defines for max tag length, > in fs/nfs/nfs4xdr.c, > /* NFSv4 COMPOUND tags are only wanted for debugging purposes */ > #ifdef DEBUG > #define NFS4_MAXTAGLEN 20 > #else > #define NFS4_MAXTAGLEN 0 > #endif > > in fs/nfs/callback_xdr.c, > #define CB_OP_TAGLEN_MAXSZ (512) > > in fs/nfsd/xdr4.h, > #define NFSD4_MAX_TAGLEN 128 > > in fs/nfsd/xdr4cb.h, > #define NFS4_MAXTAGLEN 20 > > But, according to rfc3530 and rfc5661, all the length should be > limited by opaque limited. Neither server nor client really make any use of tags. The client at least is never going to send a tag. The server does echo back the tag the client received. The one arguable bug here is that the spec doesn't appear to forbid the server returning a non-zero-length tag when the client sent a zero-length tag. And I don't think the client would handle that? If so, that might be better handled as a spec bug: if the most popular client has never handled it then we know that no server's ever done it. And it'd be annoying server behavior anyway, so, if it's de-facto forbidden, great. In short, maybe best to just leave all this alone unless somebody's actually seen this cause real-world problems.... --b. > > The patch site defines a common macro named NFS4_MAXTAGLEN for > all of them, limited to opaque limited. > > Kinglong Mee (4): > nfs: define NFS4_MAXTAGLEN to OPAQUE limits > nfs: use NFS4_MAXTAGLEN for cb_taglen checking > nfsd: use NFS4_MAXTAGLEN for nfsd taglen checking > nfsd: use NFS4_MAXTAGLEN defined in include/linux/nfs4.h > > fs/nfs/callback_xdr.c | 5 ++--- > fs/nfs/nfs4xdr.c | 7 ------- > fs/nfsd/nfs4xdr.c | 2 +- > fs/nfsd/xdr4.h | 1 - > fs/nfsd/xdr4cb.h | 3 ++- > include/linux/nfs4.h | 1 + > 6 files changed, 6 insertions(+), 13 deletions(-) > > -- > 2.3.4 -- To unsubscribe from this list: send the line "unsubscribe linux-nfs" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
