diff options
| author | Shaun Ruffell <sruffell@digium.com> | 2011-07-22 18:03:48 +0000 |
|---|---|---|
| committer | Shaun Ruffell <sruffell@digium.com> | 2011-07-22 18:03:48 +0000 |
| commit | de9374fcc9f27b42880bed0c3e257e255de04156 (patch) | |
| tree | 4e9e8a35f995cb7dd79ab25ebc53a490dd63ab04 | |
| parent | a93faaef686be31ac3906a8deae426b5ec927c28 (diff) | |
wcb4xxp: Prevent null pointer dereference on spanconfig
In the rare case where spanconfig is called while there is pending data
on the hdlc channel, the hdlc_getbuf interrupt could try to read from
the hdlc buffer before the channel was fully setup. This could
potentially result in a null pointer dereference. This condition has
existed since the creation of the wcb4xxp driver.
Signed-off-by: Russ Meyerriecks <rmeyerriecks@digium.com>
Signed-off-by: Shaun Ruffell <sruffell@digium.com>
Origin: http://svnview.digium.com/svn/dahdi?view=rev&rev=10079
git-svn-id: http://svn.asterisk.org/svn/dahdi/linux/branches/2.4@10080 a0bf4364-ded3-4de4-8d8a-66a801d63aff
| -rw-r--r-- | drivers/dahdi/wcb4xxp/base.c | 3 |
1 files changed, 3 insertions, 0 deletions
diff --git a/drivers/dahdi/wcb4xxp/base.c b/drivers/dahdi/wcb4xxp/base.c index 2a63f73..95d0060 100644 --- a/drivers/dahdi/wcb4xxp/base.c +++ b/drivers/dahdi/wcb4xxp/base.c @@ -2303,6 +2303,9 @@ static int b4xxp_chanconfig(struct dahdi_chan *chan, int sigtype) if (alreadyrunning && bspan->sigchan) { hdlc_stop(b4, fifo); + atomic_set(&bspan->hdlc_pending, 0); + bspan->sigactive = 0; + smp_mb(); bspan->sigchan = NULL; } |