firestream: fix memory leaks

BugLink: https://bugs.launchpad.net/bugs/1864261
[ Upstream commit fa865ba183d61c1ec8cbcab8573159c3b72b89a4 ]

In fs_open(), 'vcc' is allocated through kmalloc() and assigned to
'atm_vcc->dev_data.' In the following execution, if an error occurs, e.g.,
there is no more free channel, an error code EBUSY or ENOMEM will be
returned. However, 'vcc' is not deallocated, leading to memory leaks. Note
that, in normal cases where fs_open() returns 0, 'vcc' will be deallocated
in fs_close(). But, if fs_open() fails, there is no guarantee that
fs_close() will be invoked.

To fix this issue, deallocate 'vcc' before the error code is returned.

Signed-off-by: Wenwen Wang <wenwen@cs.uga.edu>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Kamal Mostafa <kamal@canonical.com>
Signed-off-by: Khalid Elmously <khalid.elmously@canonical.com>

diff --git a/drivers/atm/firestream.c b/drivers/atm/firestream.c
index d97c05690faa99363ac709fb237335a0678af4c0..c38eb8333b010aac17f959ab5167967a1fe3d061 100644 (file)
--- a/drivers/atm/firestream.c
+++ b/drivers/atm/firestream.c
@@ -927,6 +927,7 @@ static int fs_open(struct atm_vcc *atm_vcc)
                        }
                        if (!to) {
                                printk ("No more free channels for FS50..\n");
+                               kfree(vcc);
                                return -EBUSY;
                        }
                        vcc->channo = dev->channo;
@@ -937,6 +938,7 @@ static int fs_open(struct atm_vcc *atm_vcc)
                        if (((DO_DIRECTION(rxtp) && dev->atm_vccs[vcc->channo])) ||
                            ( DO_DIRECTION(txtp) && test_bit (vcc->channo, dev->tx_inuse))) {
                                printk ("Channel is in use for FS155.\n");
+                               kfree(vcc);
                                return -EBUSY;
                        }
                }
@@ -950,6 +952,7 @@ static int fs_open(struct atm_vcc *atm_vcc)
                            tc, sizeof (struct fs_transmit_config));
                if (!tc) {
                        fs_dprintk (FS_DEBUG_OPEN, "fs: can't alloc transmit_config.\n");
+                       kfree(vcc);
                        return -ENOMEM;
                }