[PATCH 2/3 v3] kernel: Move groups_sort to the caller of set_groups.

From: Thiago Rafael Becker
Date: Tue Dec 05 2017 - 09:06:07 EST


The responsibility for calling groups_sort is now on the caller
of set_groups.

Signed-off-by: Thiago Rafael Becker <thiago.becker@xxxxxxxxx>
---
fs/nfsd/auth.c | 3 +++
kernel/groups.c | 1 +
kernel/uid16.c | 1 +
net/sunrpc/auth_gss/gss_rpc_xdr.c | 1 +
net/sunrpc/auth_gss/svcauth_gss.c | 1 +
net/sunrpc/svcauth_unix.c | 8 ++++++++
6 files changed, 15 insertions(+)

diff --git a/fs/nfsd/auth.c b/fs/nfsd/auth.c
index 697f8ae..7b5099b 100644
--- a/fs/nfsd/auth.c
+++ b/fs/nfsd/auth.c
@@ -60,6 +60,9 @@ int nfsd_setuser(struct svc_rqst *rqstp, struct svc_export *exp)
gi->gid[i] = exp->ex_anon_gid;
else
gi->gid[i] = rqgi->gid[i];
+
+ /* Should be race free as long as each thread allocates a new gi */
+ groups_sort(gi);
}
} else {
gi = get_group_info(rqgi);
diff --git a/kernel/groups.c b/kernel/groups.c
index 4c9c9ed..17073a9 100644
--- a/kernel/groups.c
+++ b/kernel/groups.c
@@ -208,6 +208,7 @@ SYSCALL_DEFINE2(setgroups, int, gidsetsize, gid_t __user *, grouplist)
return retval;
}

+ groups_sort(group_info);
retval = set_current_groups(group_info);
put_group_info(group_info);

diff --git a/kernel/uid16.c b/kernel/uid16.c
index ce74a49..ef1da2a 100644
--- a/kernel/uid16.c
+++ b/kernel/uid16.c
@@ -192,6 +192,7 @@ SYSCALL_DEFINE2(setgroups16, int, gidsetsize, old_gid_t __user *, grouplist)
return retval;
}

+ groups_sort(group_info);
retval = set_current_groups(group_info);
put_group_info(group_info);

diff --git a/net/sunrpc/auth_gss/gss_rpc_xdr.c b/net/sunrpc/auth_gss/gss_rpc_xdr.c
index c4778ca..444380f 100644
--- a/net/sunrpc/auth_gss/gss_rpc_xdr.c
+++ b/net/sunrpc/auth_gss/gss_rpc_xdr.c
@@ -231,6 +231,7 @@ static int gssx_dec_linux_creds(struct xdr_stream *xdr,
goto out_free_groups;
creds->cr_group_info->gid[i] = kgid;
}
+ groups_sort(creds->cr_group_info);

return 0;
out_free_groups:
diff --git a/net/sunrpc/auth_gss/svcauth_gss.c b/net/sunrpc/auth_gss/svcauth_gss.c
index 5dd4e6c..2653119 100644
--- a/net/sunrpc/auth_gss/svcauth_gss.c
+++ b/net/sunrpc/auth_gss/svcauth_gss.c
@@ -481,6 +481,7 @@ static int rsc_parse(struct cache_detail *cd,
goto out;
rsci.cred.cr_group_info->gid[i] = kgid;
}
+ groups_sort(rsci.cred.cr_group_info);

/* mech name */
len = qword_get(&mesg, buf, mlen);
diff --git a/net/sunrpc/svcauth_unix.c b/net/sunrpc/svcauth_unix.c
index 740b67d..99841e1 100644
--- a/net/sunrpc/svcauth_unix.c
+++ b/net/sunrpc/svcauth_unix.c
@@ -20,6 +20,7 @@


#include "netns.h"
+void groups_sort(struct group_info *group_info);

/*
* AUTHUNIX and AUTHNULL credentials are both handled here.
@@ -520,6 +521,12 @@ static int unix_gid_parse(struct cache_detail *cd,
ug.gi->gid[i] = kgid;
}

+ /* Sort the groups before inserting this entry
+ * into the cache to avoid future corrutpions
+ * by multiple simultaneous attempts to sort this
+ * entry.
+ */
+ groups_sort(ug.gi);
ugp = unix_gid_lookup(cd, uid);
if (ugp) {
struct cache_head *ch;
@@ -819,6 +826,7 @@ svcauth_unix_accept(struct svc_rqst *rqstp, __be32 *authp)
kgid_t kgid = make_kgid(&init_user_ns, svc_getnl(argv));
cred->cr_group_info->gid[i] = kgid;
}
+ groups_sort(cred->cr_group_info);
if (svc_getu32(argv) != htonl(RPC_AUTH_NULL) || svc_getu32(argv) != 0) {
*authp = rpc_autherr_badverf;
return SVC_DENIED;
--
2.9.5