[PATCH] 9p: Fix possible regressions when ->get_sb fails.

From: Abhishek Kulkarni
Date: Tue Jul 21 2009 - 02:05:36 EST


->get_sb can fail causing some badness. this patch fixes
* clear sb->fs_s_info in kill_sb.
* deactivate_locked_super() calls kill_sb (v9fs_kill_super) which closes the
destroys the client, clunks all its fids and closes the v9fs session.
Attempting to do it twice will cause an oops.

Signed-off-by: Abhishek Kulkarni <adkulkar@xxxxxxxxxxxx>
---
:100644 100644 b5295fd... 2f8a3f2... M fs/9p/vfs_super.c
fs/9p/vfs_super.c | 11 +++++++----
1 files changed, 7 insertions(+), 4 deletions(-)

diff --git a/fs/9p/vfs_super.c b/fs/9p/vfs_super.c
index b5295fd..2f8a3f2 100644
--- a/fs/9p/vfs_super.c
+++ b/fs/9p/vfs_super.c
@@ -118,7 +118,6 @@ static int v9fs_get_sb(struct file_system_type *fs_type, int flags,

P9_DPRINTK(P9_DEBUG_VFS, " \n");

- st = NULL;
v9ses = kzalloc(sizeof(struct v9fs_session_info), GFP_KERNEL);
if (!v9ses)
return -ENOMEM;
@@ -168,10 +167,8 @@ P9_DPRINTK(P9_DEBUG_VFS, " simple set mount, return 0\n");
simple_set_mnt(mnt, sb);
return 0;

-release_sb:
- deactivate_locked_super(sb);
-
free_stat:
+ p9stat_free(st);
kfree(st);

clunk_fid:
@@ -180,7 +177,12 @@ clunk_fid:
close_session:
v9fs_session_close(v9ses);
kfree(v9ses);
+ return retval;

+release_sb:
+ p9stat_free(st);
+ kfree(st);
+ deactivate_locked_super(sb);
return retval;
}

@@ -202,6 +204,7 @@ static void v9fs_kill_super(struct super_block *s)

v9fs_session_close(v9ses);
kfree(v9ses);
+ s->s_fs_info = NULL;
P9_DPRINTK(P9_DEBUG_VFS, "exiting kill_super\n");
}

--
1.6.0.4

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