SELinux: more GFP_NOFS fixups to prevent selinux from re-entering the fs code

More cases where SELinux must not re-enter the fs code. Called from the
d_instantiate security hook.

Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: James Morris <jmorris@namei.org>

3 files changed, 13 insertions, 9 deletions

diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c
index 820d07a60ab0..89bb6d36c0a7 100644
--- a/security/selinux/hooks.c
+++ b/security/selinux/hooks.c
@@ -1143,7 +1143,7 @@ static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dent
                 }
 
                 len = INITCONTEXTLEN;
-                context = kmalloc(len, GFP_KERNEL);
+                context = kmalloc(len, GFP_NOFS);
                 if (!context) {
                         rc = -ENOMEM;
                         dput(dentry);
@@ -1161,7 +1161,7 @@ static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dent
                         }
                         kfree(context);
                         len = rc;
-                        context = kmalloc(len, GFP_KERNEL);
+                        context = kmalloc(len, GFP_NOFS);
                         if (!context) {
                                 rc = -ENOMEM;
                                 dput(dentry);
@@ -1185,7 +1185,8 @@ static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dent
                         rc = 0;
                 } else {
                         rc = security_context_to_sid_default(context, rc, &sid,
-                                                             sbsec->def_sid);
+                                                             sbsec->def_sid,
+                                                             GFP_NOFS);
                         if (rc) {
                                 printk(KERN_WARNING "%s:  context_to_sid(%s) "
                                        "returned %d for dev=%s ino=%ld\n",
diff --git a/security/selinux/include/security.h b/security/selinux/include/security.h
index f7d2f03781f2..44e12ec88090 100644
--- a/security/selinux/include/security.h
+++ b/security/selinux/include/security.h
@@ -86,7 +86,8 @@ int security_sid_to_context(u32 sid, char **scontext,
 int security_context_to_sid(char *scontext, u32 scontext_len,
         u32 *out_sid);
 
-int security_context_to_sid_default(char *scontext, u32 scontext_len, u32 *out_sid, u32 def_sid);
+int security_context_to_sid_default(char *scontext, u32 scontext_len,
+                                    u32 *out_sid, u32 def_sid, gfp_t gfp_flags);
 
 int security_get_user_sids(u32 callsid, char *username,
                            u32 **sids, u32 *nel);
diff --git a/security/selinux/ss/services.c b/security/selinux/ss/services.c
index f37418601215..3f2bad28ee7b 100644
--- a/security/selinux/ss/services.c
+++ b/security/selinux/ss/services.c
@@ -680,7 +680,8 @@ out:
 
 }
 
-static int security_context_to_sid_core(char *scontext, u32 scontext_len, u32 *sid, u32 def_sid)
+static int security_context_to_sid_core(char *scontext, u32 scontext_len,
+                                        u32 *sid, u32 def_sid, gfp_t gfp_flags)
 {
         char *scontext2;
         struct context context;
@@ -709,7 +710,7 @@ static int security_context_to_sid_core(char *scontext, u32 scontext_len, u32 *s
            null suffix to the copy to avoid problems with the existing
            attr package, which doesn't view the null terminator as part
            of the attribute value. */
-        scontext2 = kmalloc(scontext_len+1,GFP_KERNEL);
+        scontext2 = kmalloc(scontext_len+1, gfp_flags);
         if (!scontext2) {
                 rc = -ENOMEM;
                 goto out;
@@ -809,7 +810,7 @@ out:
 int security_context_to_sid(char *scontext, u32 scontext_len, u32 *sid)
 {
         return security_context_to_sid_core(scontext, scontext_len,
-                                            sid, SECSID_NULL);
+                                            sid, SECSID_NULL, GFP_KERNEL);
 }
 
 /**
@@ -829,10 +830,11 @@ int security_context_to_sid(char *scontext, u32 scontext_len, u32 *sid)
  * Returns -%EINVAL if the context is invalid, -%ENOMEM if insufficient
  * memory is available, or 0 on success.
  */
-int security_context_to_sid_default(char *scontext, u32 scontext_len, u32 *sid, u32 def_sid)
+int security_context_to_sid_default(char *scontext, u32 scontext_len, u32 *sid,
+                                    u32 def_sid, gfp_t gfp_flags)
 {
         return security_context_to_sid_core(scontext, scontext_len,
-                                            sid, def_sid);
+                                            sid, def_sid, gfp_flags);
 }
 
 static int compute_sid_handle_invalid_context(