diff options
| author | Ian Abbott <abbotti@mev.co.uk> | 2012-10-03 16:25:19 +0100 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2012-10-31 10:10:00 -0700 |
| commit | 3792dd12ee4419bc276cd321c8f74506a37aa93d (patch) | |
| tree | 3b405e0f6373afd92fc124c4365839a05c60d957 | |
| parent | 6f9445326d4a262a863cc634fd377c5ca562e17d (diff) | |
staging: comedi: amplc_pc263: fix possible NULL deref during detach
commit 1d1171ffda585c1cab7bd7cf4bd8f8fd5923fb4a upstream.
`pc263_detach()` is called by the comedi core to clean up if either
`pc263_attach()` or `pc263_attach_pci()` returns an error. It sets
`thisboard` to the return value of `comedi_board(dev)` and assumes it is
non-null. This is a valid assumption if `pc263_attach()` fails, but not
if `pc263_attach_pci()` fails, leading to a possible NULL pointer
dereference.
Check `thisboard` at the top of `pc263_detach()` and return early if it
is `NULL`. This is okay because no other resources need cleaning up in
this case.
Signed-off-by: Ian Abbott <abbotti@mev.co.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -rw-r--r-- | drivers/staging/comedi/drivers/amplc_pc263.c | 3 |
1 files changed, 3 insertions, 0 deletions
diff --git a/drivers/staging/comedi/drivers/amplc_pc263.c b/drivers/staging/comedi/drivers/amplc_pc263.c index 8191c4e28e0..8c0fbd1ceea 100644 --- a/drivers/staging/comedi/drivers/amplc_pc263.c +++ b/drivers/staging/comedi/drivers/amplc_pc263.c @@ -310,8 +310,11 @@ static int __devinit pc263_attach_pci(struct comedi_device *dev, static void pc263_detach(struct comedi_device *dev) { + const struct pc263_board *thisboard = comedi_board(dev); struct pci_dev *pcidev = comedi_to_pci_dev(dev); + if (!thisboard) + return; if (pcidev) { if (dev->iobase) comedi_pci_disable(pcidev); |