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| author | Tilman Schmidt <tilman@imap.cc> | 2014-10-11 13:46:30 +0200 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2014-10-14 15:05:35 -0400 |
| commit | 86f8ef2c4802ac9dbe0c8c1c12670bd915a13013 (patch) | |
| tree | ea00760072953a797e6d42ef0ce252cd9556d937 /drivers/isdn | |
| parent | 340184b35ac8786bdb574d2c8ce8e4f1269ec4da (diff) | |
| download | linux-86f8ef2c4802ac9dbe0c8c1c12670bd915a13013.tar.gz linux-86f8ef2c4802ac9dbe0c8c1c12670bd915a13013.tar.bz2 linux-86f8ef2c4802ac9dbe0c8c1c12670bd915a13013.zip | |
isdn/gigaset: fix usb_gigaset write_cmd result race
In usb_gigaset function gigaset_write_cmd(), the length field of
the command buffer structure could be cleared by the transmit
tasklet before it was used for the function's return value.
Fix by copying to a local variable before scheduling the tasklet.
Signed-off-by: Tilman Schmidt <tilman@imap.cc>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'drivers/isdn')
| -rw-r--r-- | drivers/isdn/gigaset/usb-gigaset.c | 4 |
1 files changed, 3 insertions, 1 deletions
diff --git a/drivers/isdn/gigaset/usb-gigaset.c b/drivers/isdn/gigaset/usb-gigaset.c index 82e91ba1acd3..a8e652dac54d 100644 --- a/drivers/isdn/gigaset/usb-gigaset.c +++ b/drivers/isdn/gigaset/usb-gigaset.c @@ -497,6 +497,7 @@ static int send_cb(struct cardstate *cs, struct cmdbuf_t *cb) static int gigaset_write_cmd(struct cardstate *cs, struct cmdbuf_t *cb) { unsigned long flags; + int len; gigaset_dbg_buffer(cs->mstate != MS_LOCKED ? DEBUG_TRANSCMD : DEBUG_LOCKCMD, @@ -515,10 +516,11 @@ static int gigaset_write_cmd(struct cardstate *cs, struct cmdbuf_t *cb) spin_unlock_irqrestore(&cs->cmdlock, flags); spin_lock_irqsave(&cs->lock, flags); + len = cb->len; if (cs->connected) tasklet_schedule(&cs->write_tasklet); spin_unlock_irqrestore(&cs->lock, flags); - return cb->len; + return len; } static int gigaset_write_room(struct cardstate *cs) |