diff options
| author | Dominik Brodowski <linux@dominikbrodowski.net> | 2010-08-03 09:33:45 +0200 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@suse.de> | 2010-08-13 13:30:39 -0700 |
| commit | 203824bea46cc2d9809833e77dd39780d5bcb20c (patch) | |
| tree | 1708d9e6896666186d029cc71bb2a5388b48e72a /drivers | |
| parent | 4fbb306c756c548a75d480141e327111e4d94d20 (diff) | |
pcmcia: avoid buffer overflow in pcmcia_setup_isa_irq
commit 127c03cdbad9bd5af5d7f33bd31a1015a90cb77f upstream.
NR_IRQS may be as low as 16, causing a (harmless?) buffer overflow in
pcmcia_setup_isa_irq():
static u8 pcmcia_used_irq[NR_IRQS];
...
if ((try < 32) && pcmcia_used_irq[irq])
continue;
This is read-only, so if this address would be non-zero, it would just
mean we would not attempt an IRQ >= NR_IRQS -- which would fail anyway!
And as request_irq() fails for an irq >= NR_IRQS, the setting code path:
pcmcia_used_irq[irq]++;
is never reached as well.
Reported-by: Christoph Fritz <chf.fritz@googlemail.com>
Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
Signed-off-by: Christoph Fritz <chf.fritz@googlemail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Diffstat (limited to 'drivers')
| -rw-r--r-- | drivers/pcmcia/pcmcia_resource.c | 5 |
1 files changed, 4 insertions, 1 deletions
diff --git a/drivers/pcmcia/pcmcia_resource.c b/drivers/pcmcia/pcmcia_resource.c index a4cd9adfcbc..015e27458d8 100644 --- a/drivers/pcmcia/pcmcia_resource.c +++ b/drivers/pcmcia/pcmcia_resource.c @@ -651,7 +651,7 @@ EXPORT_SYMBOL(__pcmcia_request_exclusive_irq); #ifdef CONFIG_PCMCIA_PROBE /* mask of IRQs already reserved by other cards, we should avoid using them */ -static u8 pcmcia_used_irq[NR_IRQS]; +static u8 pcmcia_used_irq[32]; static irqreturn_t test_action(int cpl, void *dev_id) { @@ -674,6 +674,9 @@ static int pcmcia_setup_isa_irq(struct pcmcia_device *p_dev, int type) for (try = 0; try < 64; try++) { irq = try % 32; + if (irq > NR_IRQS) + continue; + /* marked as available by driver, not blocked by userspace? */ if (!((mask >> irq) & 1)) continue; |