IB/hfi1: Fix for potential refcount leak in hfi1_open_file()

[ Upstream commit 2b1e7fe16124e86ee9242aeeee859c79a843e3a2 ]

The dd refcount is speculatively incremented prior to allocating
the fd memory with kzalloc(). If that kzalloc() failed the dd
refcount leaks.
Increment refcount on kzalloc success.

Fixes: e11ffbd57520 ("IB/hfi1: Do not free hfi1 cdev parent structure early")
Reviewed-by: Michael J Ruhl <michael.j.ruhl@intel.com>
Signed-off-by: Alex Estrin <alex.estrin@intel.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Alex Estrin 2018-02-01 10:43:58 -08:00 committed by Greg Kroah-Hartman
parent 5ceae7690f
commit 8f96d408a9

View File

@ -191,9 +191,6 @@ static int hfi1_file_open(struct inode *inode, struct file *fp)
if (!atomic_inc_not_zero(&dd->user_refcount))
return -ENXIO;
/* Just take a ref now. Not all opens result in a context assign */
kobject_get(&dd->kobj);
/* The real work is performed later in assign_ctxt() */
fd = kzalloc(sizeof(*fd), GFP_KERNEL);
@ -203,6 +200,7 @@ static int hfi1_file_open(struct inode *inode, struct file *fp)
fd->mm = current->mm;
mmgrab(fd->mm);
fd->dd = dd;
kobject_get(&fd->dd->kobj);
fp->private_data = fd;
} else {
fp->private_data = NULL;