After some finite number of tries, bitshift in the calculation of timetosend at
function irdma_cm_timer_tick() will lead to out-of-bounds shift, which in this
case is an undefined behaviour. For instance, if HZ is equal to 1024, the issue
occurs after 21 tries, which will take less than
IRDMA_MAX_TIMEOUT / HZ * 21 = 252 seconds.
Lower IRDMA_DEFAULT_RETRANS from 32 to 20 to prevent out-of-bounds shift for
any HZ value less than 2048.
Found by Linux Verification Center (linuxtesting.org) with SVACE.
Fixes: 8385a875c9ee ("RDMA/irdma: Increase iWARP CM default rexmit count")
Signed-off-by: Murad Masimov <m.masimov@maxima.ru>
---
drivers/infiniband/hw/irdma/cm.h | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/infiniband/hw/irdma/cm.h b/drivers/infiniband/hw/irdma/cm.h
index 48ee285cf745..dc4ee1b185eb 100644
--- a/drivers/infiniband/hw/irdma/cm.h
+++ b/drivers/infiniband/hw/irdma/cm.h
@@ -41,7 +41,7 @@
#define TCP_OPTIONS_PADDING 3
#define IRDMA_DEFAULT_RETRYS 64
-#define IRDMA_DEFAULT_RETRANS 32
+#define IRDMA_DEFAULT_RETRANS 20
#define IRDMA_DEFAULT_TTL 0x40
#define IRDMA_DEFAULT_RTT_VAR 6
#define IRDMA_DEFAULT_SS_THRESH 0x3fffffff
--
2.39.2