Sometimes a nullpointer dereferencing occurs because of using a wrong pointer arithmetic in udp_uncompression.
This patch changes "**(hc06_ptr + 3)" to the right one "*(*hc06_ptr + 3)". Dereferencing like "**(hc06_ptr + 3)" works in a random case only. Signed-off-by: Alexander Aring <alex.ar...@gmail.com> --- net/ieee802154/6lowpan_iphc.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/net/ieee802154/6lowpan_iphc.c b/net/ieee802154/6lowpan_iphc.c index 88e7da5..8bbe28e 100644 --- a/net/ieee802154/6lowpan_iphc.c +++ b/net/ieee802154/6lowpan_iphc.c @@ -548,7 +548,7 @@ static void compress_udp_header(u8 **hc06_ptr, struct sk_buff *skb) LOWPAN_NHC_UDP_4BIT_PORT)) { pr_debug("UDP header: both ports compression to 4 bits\n"); **hc06_ptr = LOWPAN_NHC_UDP_CS_P_11; - **(hc06_ptr + 1) = /* subtraction is faster */ + *(*hc06_ptr + 1) = /* subtraction is faster */ (u8)((uh->dest - LOWPAN_NHC_UDP_4BIT_PORT) + ((uh->source & LOWPAN_NHC_UDP_4BIT_PORT) << 4)); *hc06_ptr += 2; @@ -557,14 +557,14 @@ static void compress_udp_header(u8 **hc06_ptr, struct sk_buff *skb) pr_debug("UDP header: remove 8 bits of dest\n"); **hc06_ptr = LOWPAN_NHC_UDP_CS_P_01; memcpy(*hc06_ptr + 1, &uh->source, 2); - **(hc06_ptr + 3) = (u8)(uh->dest - LOWPAN_NHC_UDP_8BIT_PORT); + *(*hc06_ptr + 3) = (u8)(uh->dest - LOWPAN_NHC_UDP_8BIT_PORT); *hc06_ptr += 4; } else if ((uh->source & LOWPAN_NHC_UDP_8BIT_MASK) == LOWPAN_NHC_UDP_8BIT_PORT) { pr_debug("UDP header: remove 8 bits of source\n"); **hc06_ptr = LOWPAN_NHC_UDP_CS_P_10; memcpy(*hc06_ptr + 1, &uh->dest, 2); - **(hc06_ptr + 3) = (u8)(uh->source - LOWPAN_NHC_UDP_8BIT_PORT); + *(*hc06_ptr + 3) = (u8)(uh->source - LOWPAN_NHC_UDP_8BIT_PORT); *hc06_ptr += 4; } else { pr_debug("UDP header: can't compress\n"); -- 1.8.5.1 ------------------------------------------------------------------------------ Rapidly troubleshoot problems before they affect your business. Most IT organizations don't have a clear picture of how application performance affects their revenue. With AppDynamics, you get 100% visibility into your Java,.NET, & PHP application. Start your 15-day FREE TRIAL of AppDynamics Pro! http://pubads.g.doubleclick.net/gampad/clk?id=84349831&iu=/4140/ostg.clktrk _______________________________________________ Linux-zigbee-devel mailing list Linux-zigbee-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/linux-zigbee-devel