-stable review patch. If anyone has any objections, please let us know.
---------------------
From: Casey Schaufler <[email protected]>
upstream commit: e97dcb0eadbb821eccd549d4987b653cf61e2374
The d_instantiate hook for Smack can hang on the root inode of a
filesystem if the file system code has not really done all the set-up.
Fuse is known to encounter this problem.
This change detects an attempt to instantiate a root inode and addresses
it early in the processing, before any attempt is made to do something
that might hang.
Signed-off-by: Casey Schaufler <[email protected]>
Tested-by: Luiz Fernando N. Capitulino <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>
Signed-off-by: Chris Wright <[email protected]>
---
security/smack/smack_lsm.c | 12 ++++++++++++
1 file changed, 12 insertions(+)
--- a/security/smack/smack_lsm.c
+++ b/security/smack/smack_lsm.c
@@ -1865,6 +1865,18 @@ static void smack_d_instantiate(struct d
final = sbsp->smk_default;
/*
+ * If this is the root inode the superblock
+ * may be in the process of initialization.
+ * If that is the case use the root value out
+ * of the superblock.
+ */
+ if (opt_dentry->d_parent == opt_dentry) {
+ isp->smk_inode = sbsp->smk_root;
+ isp->smk_flags |= SMK_INODE_INSTANT;
+ goto unlockandout;
+ }
+
+ /*
* This is pretty hackish.
* Casey says that we shouldn't have to do
* file system specific code, but it does help
--