mirrors/linux-stable
1
0
Fork 0
mirror of https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git synced 2024-09-30 14:19:16 +00:00
Code Issues Releases Wiki Activity

NFSv4.1: Fix a race in set_pnfs_layoutdriver

Browse source 
The call to try_module_get() dereferences ld_type outside the
spin locks, which means that it may be pointing to garbage if
a module unload was in progress.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
This commit is contained in:
Trond Myklebust 2012-06-15 13:02:58 -04:00
parent 2a4c8994ee
commit 0a9c63fae7
1 changed files with 4 additions and 4 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

8
fs/nfs/pnfs.c
View file

@ -70,6 +70,10 @@ find_pnfs_driver(u32 id)
spin_lock(&pnfs_spinlock);
local = find_pnfs_driver_locked(id);
if (local != NULL && !try_module_get(local->owner)) {
dprintk("%s: Could not grab reference on module\n", __func__);
local = NULL;
}
spin_unlock(&pnfs_spinlock);
return local;
}
@ -118,10 +122,6 @@ set_pnfs_layoutdriver(struct nfs_server *server, const struct nfs_fh *mntfh,
goto out_no_driver;
}
}
if (!try_module_get(ld_type->owner)) {
dprintk("%s: Could not grab reference on module\n", __func__);
goto out_no_driver;
}
server->pnfs_curr_ld = ld_type;
if (ld_type->set_layoutdriver
&& ld_type->set_layoutdriver(server, mntfh)) {