Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs

Pull vfs changes from Al Viro.
 "A lot of misc stuff.  The obvious groups:
   * Miklos' atomic_open series; kills the damn abuse of
     ->d_revalidate() by NFS, which was the major stumbling block for
     all work in that area.
   * ripping security_file_mmap() and dealing with deadlocks in the
     area; sanitizing the neighborhood of vm_mmap()/vm_munmap() in
     general.
   * ->encode_fh() switched to saner API; insane fake dentry in
     mm/cleancache.c gone.
   * assorted annotations in fs (endianness, __user)
   * parts of Artem's ->s_dirty work (jff2 and reiserfs parts)
   * ->update_time() work from Josef.
   * other bits and pieces all over the place.

  Normally it would've been in two or three pull requests, but
  signal.git stuff had eaten a lot of time during this cycle ;-/"

Fix up trivial conflicts in Documentation/filesystems/vfs.txt (the
'truncate_range' inode method was removed by the VM changes, the VFS
update adds an 'update_time()' method), and in fs/btrfs/ulist.[ch] (due
to sparse fix added twice, with other changes nearby).

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (95 commits)
  nfs: don't open in ->d_revalidate
  vfs: retry last component if opening stale dentry
  vfs: nameidata_to_filp(): don't throw away file on error
  vfs: nameidata_to_filp(): inline __dentry_open()
  vfs: do_dentry_open(): don't put filp
  vfs: split __dentry_open()
  vfs: do_last() common post lookup
  vfs: do_last(): add audit_inode before open
  vfs: do_last(): only return EISDIR for O_CREAT
  vfs: do_last(): check LOOKUP_DIRECTORY
  vfs: do_last(): make ENOENT exit RCU safe
  vfs: make follow_link check RCU safe
  vfs: do_last(): use inode variable
  vfs: do_last(): inline walk_component()
  vfs: do_last(): make exit RCU safe
  vfs: split do_lookup()
  Btrfs: move over to use ->update_time
  fs: introduce inode operation ->update_time
  reiserfs: get rid of resierfs_sync_super
  reiserfs: mark the superblock as dirty a bit later
  ...

1 files changed, 46 insertions, 5 deletions

diff --git a/security/security.c b/security/security.c
index 5497a57fba01..3efc9b12aef4 100644
--- a/security/security.c
+++ b/security/security.c
@@ -20,6 +20,9 @@
 #include <linux/ima.h>
 #include <linux/evm.h>
 #include <linux/fsnotify.h>
+#include <linux/mman.h>
+#include <linux/mount.h>
+#include <linux/personality.h>
 #include <net/flow.h>
 
 #define MAX_LSM_EVM_XATTR       2
@@ -657,18 +660,56 @@ int security_file_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
         return security_ops->file_ioctl(file, cmd, arg);
 }
 
-int security_file_mmap(struct file *file, unsigned long reqprot,
-                        unsigned long prot, unsigned long flags,
-                        unsigned long addr, unsigned long addr_only)
+static inline unsigned long mmap_prot(struct file *file, unsigned long prot)
 {
-        int ret;
+        /*
+         * Does we have PROT_READ and does the application expect
+         * it to imply PROT_EXEC?  If not, nothing to talk about...
+         */
+        if ((prot & (PROT_READ | PROT_EXEC)) != PROT_READ)
+                return prot;
+        if (!(current->personality & READ_IMPLIES_EXEC))
+                return prot;
+        /*
+         * if that's an anonymous mapping, let it.
+         */
+        if (!file)
+                return prot | PROT_EXEC;
+        /*
+         * ditto if it's not on noexec mount, except that on !MMU we need
+         * BDI_CAP_EXEC_MMAP (== VM_MAYEXEC) in this case
+         */
+        if (!(file->f_path.mnt->mnt_flags & MNT_NOEXEC)) {
+#ifndef CONFIG_MMU
+                unsigned long caps = 0;
+                struct address_space *mapping = file->f_mapping;
+                if (mapping && mapping->backing_dev_info)
+                        caps = mapping->backing_dev_info->capabilities;
+                if (!(caps & BDI_CAP_EXEC_MAP))
+                        return prot;
+#endif
+                return prot | PROT_EXEC;
+        }
+        /* anything on noexec mount won't get PROT_EXEC */
+        return prot;
+}
 
-        ret = security_ops->file_mmap(file, reqprot, prot, flags, addr, addr_only);
+int security_mmap_file(struct file *file, unsigned long prot,
+                        unsigned long flags)
+{
+        int ret;
+        ret = security_ops->mmap_file(file, prot,
+                                        mmap_prot(file, prot), flags);
         if (ret)
                 return ret;
         return ima_file_mmap(file, prot);
 }
 
+int security_mmap_addr(unsigned long addr)
+{
+        return security_ops->mmap_addr(addr);
+}
+
 int security_file_mprotect(struct vm_area_struct *vma, unsigned long reqprot,
                             unsigned long prot)
 {