[PATCH] [v3] infiniband: i40iw, nes: don't use wall time for TCP sequence numbers
From: Arnd Bergmann <arnd@arndb.de>
Date: 2018-07-09 08:36:18
The nes infiniband driver uses current_kernel_time() to get a nanosecond
granunarity timestamp to initialize its tcp sequence counters. This is
one of only a few remaining users of that deprecated function, so we
should try to get rid of it.
Aside from using a deprecated API, there are several problems I see here:
- Using a CLOCK_REALTIME based time source makes it predictable in
case the time base is synchronized.
- Using a coarse timestamp means it only gets updated once per jiffie,
making it even more predictable in order to avoid having to access
the hardware clock source
- The upper 2 bits are always zero because the nanoseconds are at most
999999999.
For the Linux TCP implementation, we use secure_tcp_seq(), which appears
to be appropriate here as well, and solves all the above problems.
i40iw uses a variant of the same code, so I do that same thing there
for ipv4. Unlike nes, i40e also supports ipv6, which needs to call
secure_tcpv6_seq instead.
Acked-by: Shiraz Saleem <redacted>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
---
v2: use secure_tcpv6_seq for IPv6 support as suggested by Shiraz Saleem.
v3: add a soft IPv6 dependency to prevent a link error with CONFIG_IPV6=m,
this now forces i40iw to be a module as well, add an IS_ENABLED()
check to avoid calling it when IPV6 is completely disabled.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
---
drivers/infiniband/hw/i40iw/Kconfig | 1 +
drivers/infiniband/hw/i40iw/i40iw_cm.c | 26 +++++++++++++++++++++-----
drivers/infiniband/hw/nes/nes_cm.c | 8 +++++---
net/core/secure_seq.c | 1 +
4 files changed, 28 insertions(+), 8 deletions(-)
diff --git a/drivers/infiniband/hw/i40iw/Kconfig b/drivers/infiniband/hw/i40iw/Kconfig
index 2962979c06e9..d867ef1ac72a 100644
--- a/drivers/infiniband/hw/i40iw/Kconfig
+++ b/drivers/infiniband/hw/i40iw/Kconfig@@ -1,6 +1,7 @@ config INFINIBAND_I40IW tristate "Intel(R) Ethernet X722 iWARP Driver" depends on INET && I40E + depends on IPV6 || !IPV6 depends on PCI select GENERIC_ALLOCATOR ---help---
diff --git a/drivers/infiniband/hw/i40iw/i40iw_cm.c b/drivers/infiniband/hw/i40iw/i40iw_cm.c
index 7b2655128b9f..423818a7d333 100644
--- a/drivers/infiniband/hw/i40iw/i40iw_cm.c
+++ b/drivers/infiniband/hw/i40iw/i40iw_cm.c@@ -57,6 +57,7 @@ #include <net/addrconf.h> #include <net/ip6_route.h> #include <net/ip_fib.h> +#include <net/secure_seq.h> #include <net/tcp.h> #include <asm/checksum.h>
@@ -2164,7 +2165,6 @@ static struct i40iw_cm_node *i40iw_make_cm_node( struct i40iw_cm_listener *listener) { struct i40iw_cm_node *cm_node; - struct timespec ts; int oldarpindex; int arpindex; struct net_device *netdev = iwdev->netdev;
@@ -2214,10 +2214,26 @@ static struct i40iw_cm_node *i40iw_make_cm_node( cm_node->tcp_cntxt.rcv_wscale = I40IW_CM_DEFAULT_RCV_WND_SCALE; cm_node->tcp_cntxt.rcv_wnd = I40IW_CM_DEFAULT_RCV_WND_SCALED >> I40IW_CM_DEFAULT_RCV_WND_SCALE; - ts = current_kernel_time(); - cm_node->tcp_cntxt.loc_seq_num = ts.tv_nsec; - cm_node->tcp_cntxt.mss = (cm_node->ipv4) ? (iwdev->vsi.mtu - I40IW_MTU_TO_MSS_IPV4) : - (iwdev->vsi.mtu - I40IW_MTU_TO_MSS_IPV6); + if (cm_node->ipv4) { + cm_node->tcp_cntxt.loc_seq_num = secure_tcp_seq(htonl(cm_node->loc_addr[0]), + htonl(cm_node->rem_addr[0]), + htons(cm_node->loc_port), + htons(cm_node->rem_port)); + cm_node->tcp_cntxt.mss = iwdev->vsi.mtu - I40IW_MTU_TO_MSS_IPV4; + } else if (IS_ENABLED(CONFIG_IPV6)) { + __be32 loc[4] = { + htonl(cm_node->loc_addr[0]), htonl(cm_node->loc_addr[1]), + htonl(cm_node->loc_addr[2]), htonl(cm_node->loc_addr[3]) + }; + __be32 rem[4] = { + htonl(cm_node->rem_addr[0]), htonl(cm_node->rem_addr[1]), + htonl(cm_node->rem_addr[2]), htonl(cm_node->rem_addr[3]) + }; + cm_node->tcp_cntxt.loc_seq_num = secure_tcpv6_seq(loc, rem, + htons(cm_node->loc_port), + htons(cm_node->rem_port)); + cm_node->tcp_cntxt.mss = iwdev->vsi.mtu - I40IW_MTU_TO_MSS_IPV6; + } cm_node->iwdev = iwdev; cm_node->dev = &iwdev->sc_dev;
diff --git a/drivers/infiniband/hw/nes/nes_cm.c b/drivers/infiniband/hw/nes/nes_cm.c
index 6cdfbf8c5674..2b67ace5b614 100644
--- a/drivers/infiniband/hw/nes/nes_cm.c
+++ b/drivers/infiniband/hw/nes/nes_cm.c@@ -58,6 +58,7 @@ #include <net/neighbour.h> #include <net/route.h> #include <net/ip_fib.h> +#include <net/secure_seq.h> #include <net/tcp.h> #include <linux/fcntl.h>
@@ -1445,7 +1446,6 @@ static struct nes_cm_node *make_cm_node(struct nes_cm_core *cm_core, struct nes_cm_listener *listener) { struct nes_cm_node *cm_node; - struct timespec ts; int oldarpindex = 0; int arpindex = 0; struct nes_device *nesdev;
@@ -1496,8 +1496,10 @@ static struct nes_cm_node *make_cm_node(struct nes_cm_core *cm_core, cm_node->tcp_cntxt.rcv_wscale = NES_CM_DEFAULT_RCV_WND_SCALE; cm_node->tcp_cntxt.rcv_wnd = NES_CM_DEFAULT_RCV_WND_SCALED >> NES_CM_DEFAULT_RCV_WND_SCALE; - ts = current_kernel_time(); - cm_node->tcp_cntxt.loc_seq_num = htonl(ts.tv_nsec); + cm_node->tcp_cntxt.loc_seq_num = secure_tcp_seq(htonl(cm_node->loc_addr), + htonl(cm_node->rem_addr), + htons(cm_node->loc_port), + htons(cm_node->rem_port)); cm_node->tcp_cntxt.mss = nesvnic->max_frame_size - sizeof(struct iphdr) - sizeof(struct tcphdr) - ETH_HLEN - VLAN_HLEN; cm_node->tcp_cntxt.rcv_nxt = 0;
diff --git a/net/core/secure_seq.c b/net/core/secure_seq.c
index 7232274de334..af6ad467ed61 100644
--- a/net/core/secure_seq.c
+++ b/net/core/secure_seq.c@@ -140,6 +140,7 @@ u32 secure_tcp_seq(__be32 saddr, __be32 daddr, &net_secret); return seq_scale(hash); } +EXPORT_SYMBOL_GPL(secure_tcp_seq); u32 secure_ipv4_port_ephemeral(__be32 saddr, __be32 daddr, __be16 dport) {
--
2.9.0