1From 003d34eebd223c16a3dbf6a970bb6e23cb7d1a24 Mon Sep 17 00:00:00 2001 2From: Simon Goldschmidt <goldsimon@gmx.de> 3Date: Fri, 27 Mar 2020 22:59:05 +0100 4Subject: [PATCH] tcp: fix sequence number comparison 5This fixes both undefined behavior (see bug #51447) as well as a possible bug 6where sequence numbers in 31 bit distance may come through. 7Conflict: NA 8Reference: https://git.savannah.gnu.org/cgit/lwip.git/commit/?id=003d34eebd223c16a3dbf6a970bb6e23cb7d1a24 9--- 10 src/include/lwip/priv/tcp_priv.h | 11 ++++------- 11 1 file changed, 4 insertions(+), 7 deletions(-) 12diff --git a/src/include/lwip/priv/tcp_priv.h b/src/include/lwip/priv/tcp_priv.h 13index 72f9126d..c84b5be8 100644 14--- a/src/include/lwip/priv/tcp_priv.h 15+++ b/src/include/lwip/priv/tcp_priv.h 16@@ -106,14 +106,11 @@ err_t tcp_process_refused_data(struct tcp_pcb *pcb); 17 #define tcp_output_nagle(tpcb) (tcp_do_output_nagle(tpcb) ? tcp_output(tpcb) : ERR_OK) 18 19 20-#define TCP_SEQ_LT(a,b) ((s32_t)((u32_t)(a) - (u32_t)(b)) < 0) 21-#define TCP_SEQ_LEQ(a,b) ((s32_t)((u32_t)(a) - (u32_t)(b)) <= 0) 22-#define TCP_SEQ_GT(a,b) ((s32_t)((u32_t)(a) - (u32_t)(b)) > 0) 23-#define TCP_SEQ_GEQ(a,b) ((s32_t)((u32_t)(a) - (u32_t)(b)) >= 0) 24+#define TCP_SEQ_LT(a,b) (((u32_t)((u32_t)(a) - (u32_t)(b)) & 0x80000000u) != 0) 25+#define TCP_SEQ_LEQ(a,b) (!(TCP_SEQ_LT(b,a))) 26+#define TCP_SEQ_GT(a,b) TCP_SEQ_LT(b,a) 27+#define TCP_SEQ_GEQ(a,b) TCP_SEQ_LEQ(b,a) 28 /* is b<=a<=c? */ 29-#if 0 /* see bug #10548 */ 30-#define TCP_SEQ_BETWEEN(a,b,c) ((c)-(b) >= (a)-(b)) 31-#endif 32 #define TCP_SEQ_BETWEEN(a,b,c) (TCP_SEQ_GEQ(a,b) && TCP_SEQ_LEQ(a,c)) 33 34 #ifndef TCP_TMR_INTERVAL 35-- 362.28.0.windows.1 37