From: Lee Jones Date: Wed, 13 Aug 2014 11:23:10 +0000 (+0100) Subject: misc: st_core: Protect unsigned value against becoming negative X-Git-Tag: v3.18-rc1~40^2~77 X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=4001998a43f4791b6e6c06df563f5d5bb3fbe4fb;p=karo-tx-linux.git misc: st_core: Protect unsigned value against becoming negative Coverity reported: This less-than-zero comparison of an unsigned value is never true. In answer to that, we only ever decrement if protos_registered is positive. We can subsequently remove the paranoid checking during unregister. Cc: gregkh@linuxfoundation.org Signed-off-by: Lee Jones --- diff --git a/drivers/misc/ti-st/st_core.c b/drivers/misc/ti-st/st_core.c index 1972d57aadb3..54be83d3efdd 100644 --- a/drivers/misc/ti-st/st_core.c +++ b/drivers/misc/ti-st/st_core.c @@ -153,8 +153,9 @@ static void st_reg_complete(struct st_data_s *st_gdata, char err) (st_gdata->list[i]->priv_data, err); pr_info("protocol %d's cb sent %d\n", i, err); if (err) { /* cleanup registered protocol */ - st_gdata->protos_registered--; st_gdata->is_registered[i] = false; + if (st_gdata->protos_registered) + st_gdata->protos_registered--; } } } @@ -639,14 +640,12 @@ long st_unregister(struct st_proto_s *proto) return -EPROTONOSUPPORT; } - st_gdata->protos_registered--; + if (st_gdata->protos_registered) + st_gdata->protos_registered--; + remove_channel_from_table(st_gdata, proto); spin_unlock_irqrestore(&st_gdata->lock, flags); - /* paranoid check */ - if (st_gdata->protos_registered < ST_EMPTY) - st_gdata->protos_registered = ST_EMPTY; - if ((st_gdata->protos_registered == ST_EMPTY) && (!test_bit(ST_REG_PENDING, &st_gdata->st_state))) { pr_info(" all chnl_ids unregistered ");