From e15465e1808542743627f13d1c0cbb7eacc82b83 Mon Sep 17 00:00:00 2001 From: Dan Carpenter Date: Tue, 16 Apr 2013 21:10:38 +0000 Subject: [PATCH] irda: small read past the end of array in debug code The "reason" can come from skb->data[] and it hasn't been capped so it can be from 0-255 instead of just 0-6. For example in irlmp_state_dtr() the code does: reason = skb->data[3]; ... irlmp_disconnect_indication(self, reason, skb); Also LMREASON has a couple other values which don't have entries in the irlmp_reasons[] array. And 0xff is a valid reason as well which means "unknown". So far as I can see we don't actually care about "reason" except for in the debug code. Signed-off-by: Dan Carpenter Signed-off-by: David S. Miller --- include/net/irda/irlmp.h | 3 ++- net/irda/iriap.c | 3 ++- net/irda/irlmp.c | 10 +++++++++- 3 files changed, 13 insertions(+), 3 deletions(-) diff --git a/include/net/irda/irlmp.h b/include/net/irda/irlmp.h index f74109144d3f..f132924cc9da 100644 --- a/include/net/irda/irlmp.h +++ b/include/net/irda/irlmp.h @@ -256,7 +256,8 @@ static inline __u32 irlmp_get_daddr(const struct lsap_cb *self) return (self && self->lap) ? self->lap->daddr : 0; } -extern const char *irlmp_reasons[]; +const char *irlmp_reason_str(LM_REASON reason); + extern int sysctl_discovery_timeout; extern int sysctl_discovery_slots; extern int sysctl_discovery; diff --git a/net/irda/iriap.c b/net/irda/iriap.c index 29340a9a6fb9..e1b37f5a2691 100644 --- a/net/irda/iriap.c +++ b/net/irda/iriap.c @@ -303,7 +303,8 @@ static void iriap_disconnect_indication(void *instance, void *sap, { struct iriap_cb *self; - IRDA_DEBUG(4, "%s(), reason=%s\n", __func__, irlmp_reasons[reason]); + IRDA_DEBUG(4, "%s(), reason=%s [%d]\n", __func__, + irlmp_reason_str(reason), reason); self = instance; diff --git a/net/irda/irlmp.c b/net/irda/irlmp.c index 6115a44c0a24..1064621da6f6 100644 --- a/net/irda/irlmp.c +++ b/net/irda/irlmp.c @@ -66,8 +66,15 @@ const char *irlmp_reasons[] = { "LM_LAP_RESET", "LM_INIT_DISCONNECT", "ERROR, NOT USED", + "UNKNOWN", }; +const char *irlmp_reason_str(LM_REASON reason) +{ + reason = min_t(size_t, reason, ARRAY_SIZE(irlmp_reasons) - 1); + return irlmp_reasons[reason]; +} + /* * Function irlmp_init (void) * @@ -747,7 +754,8 @@ void irlmp_disconnect_indication(struct lsap_cb *self, LM_REASON reason, { struct lsap_cb *lsap; - IRDA_DEBUG(1, "%s(), reason=%s\n", __func__, irlmp_reasons[reason]); + IRDA_DEBUG(1, "%s(), reason=%s [%d]\n", __func__, + irlmp_reason_str(reason), reason); IRDA_ASSERT(self != NULL, return;); IRDA_ASSERT(self->magic == LMP_LSAP_MAGIC, return;); -- GitLab