[PATCH] autofs4: panic after mount fail
Resolve the panic on failed mount of an autofs filesystem originally
reported by Mao Bibo.
It addresses two issues that happen after the mount fail. The first a NULL
pointer reference to a field (pipe) in the autofs superblock info structure
and second the lack of super block cleanup by the autofs and autofs4
modules.
Signed-off-by: Ian Kent <raven@themaw.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff --git a/fs/autofs4/inode.c b/fs/autofs4/inode.c
index 51fd859..ce7c0f1 100644
--- a/fs/autofs4/inode.c
+++ b/fs/autofs4/inode.c
@@ -99,6 +99,9 @@
struct dentry *this_parent = sbi->sb->s_root;
struct list_head *next;
+ if (!sbi->sb->s_root)
+ return;
+
spin_lock(&dcache_lock);
repeat:
next = this_parent->d_subdirs.next;
@@ -146,6 +149,14 @@
{
struct autofs_sb_info *sbi = autofs4_sbi(sb);
+ /*
+ * In the event of a failure in get_sb_nodev the superblock
+ * info is not present so nothing else has been setup, so
+ * just exit when we are called from deactivate_super.
+ */
+ if (!sbi)
+ return;
+
sb->s_fs_info = NULL;
if ( !sbi->catatonic )
@@ -310,7 +321,8 @@
s->s_fs_info = sbi;
sbi->magic = AUTOFS_SBI_MAGIC;
sbi->pipefd = -1;
- sbi->catatonic = 0;
+ sbi->pipe = NULL;
+ sbi->catatonic = 1;
sbi->exp_timeout = 0;
sbi->oz_pgrp = process_group(current);
sbi->sb = s;
@@ -388,6 +400,7 @@
goto fail_fput;
sbi->pipe = pipe;
sbi->pipefd = pipefd;
+ sbi->catatonic = 0;
/*
* Success! Install the root dentry now to indicate completion.
@@ -412,6 +425,8 @@
kfree(ino);
fail_free:
kfree(sbi);
+ s->s_fs_info = NULL;
+ kill_anon_super(s);
fail_unlock:
return -EINVAL;
}