From 2fdd6bd293b9e7dda61220538b2759fbf06f5af0 Mon Sep 17 00:00:00 2001 From: Chuck Lever Date: Wed, 21 Oct 2020 12:39:06 -0400 Subject: [PATCH] NFSD: Update the NFSv2 SETATTR argument decoder to use struct xdr_stream Signed-off-by: Chuck Lever --- fs/nfsd/nfsxdr.c | 82 +++++++++++++++++++++++++++++++++++++++++++++++++++----- 1 file changed, 76 insertions(+), 6 deletions(-) diff --git a/fs/nfsd/nfsxdr.c b/fs/nfsd/nfsxdr.c index 3d0fe03..6c87ea8 100644 --- a/fs/nfsd/nfsxdr.c +++ b/fs/nfsd/nfsxdr.c @@ -173,6 +173,79 @@ decode_sattr(__be32 *p, struct iattr *iap, struct user_namespace *userns) return p; } +static bool +svcxdr_decode_sattr(struct svc_rqst *rqstp, struct xdr_stream *xdr, + struct iattr *iap) +{ + u32 tmp1, tmp2; + __be32 *p; + + p = xdr_inline_decode(xdr, XDR_UNIT * 8); + if (!p) + return false; + + iap->ia_valid = 0; + + /* + * Some Sun clients put 0xffff in the mode field when they + * mean 0xffffffff. + */ + tmp1 = be32_to_cpup(p++); + if (tmp1 != (u32)-1 && tmp1 != 0xffff) { + iap->ia_valid |= ATTR_MODE; + iap->ia_mode = tmp1; + } + + tmp1 = be32_to_cpup(p++); + if (tmp1 != (u32)-1) { + iap->ia_uid = make_kuid(nfsd_user_namespace(rqstp), tmp1); + if (uid_valid(iap->ia_uid)) + iap->ia_valid |= ATTR_UID; + } + + tmp1 = be32_to_cpup(p++); + if (tmp1 != (u32)-1) { + iap->ia_gid = make_kgid(nfsd_user_namespace(rqstp), tmp1); + if (gid_valid(iap->ia_gid)) + iap->ia_valid |= ATTR_GID; + } + + tmp1 = be32_to_cpup(p++); + if (tmp1 != (u32)-1) { + iap->ia_valid |= ATTR_SIZE; + iap->ia_size = tmp1; + } + + tmp1 = be32_to_cpup(p++); + tmp2 = be32_to_cpup(p++); + if (tmp1 != (u32)-1 && tmp2 != (u32)-1) { + iap->ia_valid |= ATTR_ATIME | ATTR_ATIME_SET; + iap->ia_atime.tv_sec = tmp1; + iap->ia_atime.tv_nsec = tmp2 * NSEC_PER_USEC; + } + + tmp1 = be32_to_cpup(p++); + tmp2 = be32_to_cpup(p++); + if (tmp1 != (u32)-1 && tmp2 != (u32)-1) { + iap->ia_valid |= ATTR_MTIME | ATTR_MTIME_SET; + iap->ia_mtime.tv_sec = tmp1; + iap->ia_mtime.tv_nsec = tmp2 * NSEC_PER_USEC; + /* + * Passing the invalid value useconds=1000000 for mtime + * is a Sun convention for "set both mtime and atime to + * current server time". It's needed to make permissions + * checks for the "touch" program across v2 mounts to + * Solaris and Irix boxes work correctly. See description of + * sattr in section 6.1 of "NFS Illustrated" by + * Brent Callaghan, Addison-Wesley, ISBN 0-201-32750-5 + */ + if (tmp2 == 1000000) + iap->ia_valid &= ~(ATTR_ATIME_SET|ATTR_MTIME_SET); + } + + return true; +} + static __be32 * encode_fattr(struct svc_rqst *rqstp, __be32 *p, struct svc_fh *fhp, struct kstat *stat) @@ -253,14 +326,11 @@ nfssvc_decode_fhandleargs(struct svc_rqst *rqstp, __be32 *p) int nfssvc_decode_sattrargs(struct svc_rqst *rqstp, __be32 *p) { + struct xdr_stream *xdr = &rqstp->rq_arg_stream; struct nfsd_sattrargs *args = rqstp->rq_argp; - p = decode_fh(p, &args->fh); - if (!p) - return 0; - p = decode_sattr(p, &args->attrs, nfsd_user_namespace(rqstp)); - - return xdr_argsize_check(rqstp, p); + return svcxdr_decode_fhandle(xdr, &args->fh) && + svcxdr_decode_sattr(rqstp, xdr, &args->attrs); } int -- 2.7.4