From 6f6cc3205c5f10129b8a10cdf8abf85d9db48a60 Mon Sep 17 00:00:00 2001 From: "J. Bruce Fields" Date: Fri, 13 Sep 2013 17:50:42 -0400 Subject: [PATCH] nfsd: -EINVAL on invalid anonuid/gid instead of silent failure If we're going to refuse to accept these it would be polite of us to at least say so.... This introduces a slight complication since we need to grandfather in exportfs's ill-advised use of -1 uid and gid on its test_export. If it turns out there are other users passing down -1 we may need to do something else. Best might be to drop the checks entirely, but I'm not sure if other parts of the kernel might assume that a task can't run as uid or gid -1. Cc: "Eric W. Biederman" Signed-off-by: J. Bruce Fields --- fs/nfsd/export.c | 9 +++++++++ 1 file changed, 9 insertions(+) diff --git a/fs/nfsd/export.c b/fs/nfsd/export.c index af51cf9bf2e3..8513c598fabf 100644 --- a/fs/nfsd/export.c +++ b/fs/nfsd/export.c @@ -579,6 +579,13 @@ static int svc_export_parse(struct cache_detail *cd, char *mesg, int mlen) exp.ex_uuid); if (err) goto out4; + /* + * No point caching this if it would immediately expire. + * Also, this protects exportfs's dummy export from the + * anon_uid/anon_gid checks: + */ + if (exp.h.expiry_time < seconds_since_boot()) + goto out4; /* * For some reason exportfs has been passing down an * invalid (-1) uid & gid on the "dummy" export which it @@ -586,10 +593,12 @@ static int svc_export_parse(struct cache_detail *cd, char *mesg, int mlen) * sees errors from check_export we therefore need to * delay these checks till after check_export: */ + err = -EINVAL; if (!uid_valid(exp.ex_anon_uid)) goto out4; if (!gid_valid(exp.ex_anon_gid)) goto out4; + err = 0; } expp = svc_export_lookup(&exp);