2014-12-15 11:33:22

by Alan

[permalink] [raw]
Subject: [PATCH] doubletalk: probe failure causes OOPS

The code bothers to probe for the device, but on failing to find it proceeds
to try and release a NULL resource, thereby ruining it's prior good
behaviour

Resolves-Bug: https://bugzilla.kernel.org/show_bug.cgi?id=88581
Signed-off-by: Alan Cox <[email protected]>
---
drivers/staging/speakup/speakup_dtlk.c | 7 ++++---
1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/drivers/staging/speakup/speakup_dtlk.c b/drivers/staging/speakup/speakup_dtlk.c
index d7d5152..ffd85e1 100644
--- a/drivers/staging/speakup/speakup_dtlk.c
+++ b/drivers/staging/speakup/speakup_dtlk.c
@@ -325,7 +325,7 @@ static struct synth_settings *synth_interrogate(struct spk_synth *synth)

static int synth_probe(struct spk_synth *synth)
{
- unsigned int port_val = 0;
+ unsigned int port_val = 0;
int i = 0;
struct synth_settings *sp;

@@ -361,7 +361,8 @@ static int synth_probe(struct spk_synth *synth)
port_val &= 0xfbff;
if (port_val != 0x107f) {
pr_info("DoubleTalk PC: not found\n");
- synth_release_region(synth_lpc, SYNTH_IO_EXTENT);
+ if (synth_lpc)
+ synth_release_region(synth_lpc, SYNTH_IO_EXTENT);
return -ENODEV;
}
while (inw_p(synth_lpc) != 0x147f)
@@ -369,7 +370,7 @@ static int synth_probe(struct spk_synth *synth)
sp = synth_interrogate(synth);
pr_info("%s: %03x-%03x, ROM ver %s, s/n %u, driver: %s\n",
synth->long_name, synth_lpc, synth_lpc+SYNTH_IO_EXTENT - 1,
- sp->rom_version, sp->serial_number, synth->version);
+ sp->rom_version, sp->serial_number, synth->version);
synth->alive = 1;
return 0;
}