12:54 p.m.
Change the security_inode_getsecctx() interface to fill
a lsmcontext structure instead of data and length pointers.
This provides the information about which LSM created the
context so that security_release_secctx() can use the
correct hook.
Acked-by: Stephen Smalley <stephen.smalley.work(a)gmail.com>
Acked-by: Paul Moore <paul(a)paul-moore.com>
Acked-by: Chuck Lever <chuck.lever(a)oracle.com>
Reviewed-by: Kees Cook <keescook(a)chromium.org>
Reviewed-by: John Johansen <john.johansen(a)canonical.com>
Signed-off-by: Casey Schaufler <casey(a)schaufler-ca.com>
Cc: linux-nfs(a)vger.kernel.org
---
fs/nfsd/nfs4xdr.c | 23 +++++++++--------------
include/linux/security.h | 5 +++--
security/security.c | 13 +++++++++++--
3 files changed, 23 insertions(+), 18 deletions(-)
diff --git a/fs/nfsd/nfs4xdr.c b/fs/nfsd/nfs4xdr.c
index 089ec4b61ef1..fc7ba114c298 100644
--- a/fs/nfsd/nfs4xdr.c
+++ b/fs/nfsd/nfs4xdr.c
@@ -2727,11 +2727,11 @@ nfsd4_encode_layout_types(struct xdr_stream *xdr, u32
layout_types)
#ifdef CONFIG_NFSD_V4_SECURITY_LABEL
static inline __be32
nfsd4_encode_security_label(struct xdr_stream *xdr, struct svc_rqst *rqstp,
- void *context, int len)
+ struct lsmcontext *context)
{
__be32 *p;
- p = xdr_reserve_space(xdr, len + 4 + 4 + 4);
+ p = xdr_reserve_space(xdr, context->len + 4 + 4 + 4);
if (!p)
return nfserr_resource;
@@ -2741,13 +2741,13 @@ nfsd4_encode_security_label(struct xdr_stream *xdr, struct
svc_rqst *rqstp,
*/
*p++ = cpu_to_be32(0); /* lfs */
*p++ = cpu_to_be32(0); /* pi */
- p = xdr_encode_opaque(p, context, len);
+ p = xdr_encode_opaque(p, context->context, context->len);
return 0;
}
#else
static inline __be32
nfsd4_encode_security_label(struct xdr_stream *xdr, struct svc_rqst *rqstp,
- void *context, int len)
+ struct lsmcontext *context)
{ return 0; }
#endif
@@ -2844,9 +2844,7 @@ nfsd4_encode_fattr(struct xdr_stream *xdr, struct svc_fh *fhp,
int err;
struct nfs4_acl *acl = NULL;
#ifdef CONFIG_NFSD_V4_SECURITY_LABEL
- struct lsmcontext scaff; /* scaffolding */
- void *context = NULL;
- int contextlen;
+ struct lsmcontext context = { };
#endif
bool contextsupport = false;
struct nfsd4_compoundres *resp = rqstp->rq_resp;
@@ -2904,7 +2902,7 @@ nfsd4_encode_fattr(struct xdr_stream *xdr, struct svc_fh *fhp,
bmval0 & FATTR4_WORD0_SUPPORTED_ATTRS) {
if (exp->ex_flags & NFSEXP_SECURITY_LABEL)
err = security_inode_getsecctx(d_inode(dentry),
- &context, &contextlen);
+ &context);
else
err = -EOPNOTSUPP;
contextsupport = (err == 0);
@@ -3324,8 +3322,7 @@ nfsd4_encode_fattr(struct xdr_stream *xdr, struct svc_fh *fhp,
#ifdef CONFIG_NFSD_V4_SECURITY_LABEL
if (bmval2 & FATTR4_WORD2_SECURITY_LABEL) {
- status = nfsd4_encode_security_label(xdr, rqstp, context,
- contextlen);
+ status = nfsd4_encode_security_label(xdr, rqstp, &context);
if (status)
goto out;
}
@@ -3346,10 +3343,8 @@ nfsd4_encode_fattr(struct xdr_stream *xdr, struct svc_fh *fhp,
out:
#ifdef CONFIG_NFSD_V4_SECURITY_LABEL
- if (context) {
- lsmcontext_init(&scaff, context, contextlen, 0); /*scaffolding*/
- security_release_secctx(&scaff);
- }
+ if (context.context)
+ security_release_secctx(&context);
#endif /* CONFIG_NFSD_V4_SECURITY_LABEL */
kfree(acl);
if (tempfh) {
diff --git a/include/linux/security.h b/include/linux/security.h
index eed281367895..e5fd1711bf8b 100644
--- a/include/linux/security.h
+++ b/include/linux/security.h
@@ -586,7 +586,7 @@ void security_release_secctx(struct lsmcontext *cp);
void security_inode_invalidate_secctx(struct inode *inode);
int security_inode_notifysecctx(struct inode *inode, void *ctx, u32 ctxlen);
int security_inode_setsecctx(struct dentry *dentry, void *ctx, u32 ctxlen);
-int security_inode_getsecctx(struct inode *inode, void **ctx, u32 *ctxlen);
+int security_inode_getsecctx(struct inode *inode, struct lsmcontext *cp);
int security_locked_down(enum lockdown_reason what);
#else /* CONFIG_SECURITY */
@@ -1462,7 +1462,8 @@ static inline int security_inode_setsecctx(struct dentry *dentry,
void *ctx, u32
{
return -EOPNOTSUPP;
}
-static inline int security_inode_getsecctx(struct inode *inode, void **ctx, u32 *ctxlen)
+static inline int security_inode_getsecctx(struct inode *inode,
+ struct lsmcontext *cp)
{
return -EOPNOTSUPP;
}
diff --git a/security/security.c b/security/security.c
index f8d306b0dfb8..a61477c6b0f6 100644
--- a/security/security.c
+++ b/security/security.c
@@ -2398,9 +2398,18 @@ int security_inode_setsecctx(struct dentry *dentry, void *ctx, u32
ctxlen)
}
EXPORT_SYMBOL(security_inode_setsecctx);
-int security_inode_getsecctx(struct inode *inode, void **ctx, u32 *ctxlen)
+int security_inode_getsecctx(struct inode *inode, struct lsmcontext *cp)
{
- return call_int_hook(inode_getsecctx, -EOPNOTSUPP, inode, ctx, ctxlen);
+ struct security_hook_list *hp;
+
+ memset(cp, 0, sizeof(*cp));
+
+ hlist_for_each_entry(hp, &security_hook_heads.inode_getsecctx, list) {
+ cp->slot = hp->lsmid->slot;
+ return hp->hook.inode_getsecctx(inode, (void **)&cp->context,
+ &cp->len);
+ }
+ return -EOPNOTSUPP;
}
EXPORT_SYMBOL(security_inode_getsecctx);
--
2.31.1