From 35edfdc77f683c8fd27d7732af06cf6489af60a5 Mon Sep 17 00:00:00 2001 From: Josh Elsasser Date: Sat, 26 Jan 2019 14:38:33 -0800 Subject: net: set default network namespace in init_dummy_netdev() Assign a default net namespace to netdevs created by init_dummy_netdev(). Fixes a NULL pointer dereference caused by busy-polling a socket bound to an iwlwifi wireless device, which bumps the per-net BUSYPOLLRXPACKETS stat if napi_poll() received packets: BUG: unable to handle kernel NULL pointer dereference at 0000000000000190 IP: napi_busy_loop+0xd6/0x200 Call Trace: sock_poll+0x5e/0x80 do_sys_poll+0x324/0x5a0 SyS_poll+0x6c/0xf0 do_syscall_64+0x6b/0x1f0 entry_SYSCALL_64_after_hwframe+0x3d/0xa2 Fixes: 7db6b048da3b ("net: Commonize busy polling code to focus on napi_id instead of socket") Signed-off-by: Josh Elsasser Signed-off-by: David S. Miller --- net/core/dev.c | 3 +++ 1 file changed, 3 insertions(+) (limited to 'net/core/dev.c') diff --git a/net/core/dev.c b/net/core/dev.c index 82f20022259d..8e276e0192a1 100644 --- a/net/core/dev.c +++ b/net/core/dev.c @@ -8712,6 +8712,9 @@ int init_dummy_netdev(struct net_device *dev) set_bit(__LINK_STATE_PRESENT, &dev->state); set_bit(__LINK_STATE_START, &dev->state); + /* napi_busy_loop stats accounting wants this */ + dev_net_set(dev, &init_net); + /* Note : We dont allocate pcpu_refcnt for dummy devices, * because users of this 'device' dont need to change * its refcount. -- cgit v1.2.3 From 3b89ea9c5902acccdbbdec307c85edd1bf52515e Mon Sep 17 00:00:00 2001 From: Hauke Mehrtens Date: Fri, 15 Feb 2019 17:58:54 +0100 Subject: net: Fix for_each_netdev_feature on Big endian The features attribute is of type u64 and stored in the native endianes on the system. The for_each_set_bit() macro takes a pointer to a 32 bit array and goes over the bits in this area. On little Endian systems this also works with an u64 as the most significant bit is on the highest address, but on big endian the words are swapped. When we expect bit 15 here we get bit 47 (15 + 32). This patch converts it more or less to its own for_each_set_bit() implementation which works on 64 bit integers directly. This is then completely in host endianness and should work like expected. Fixes: fd867d51f ("net/core: generic support for disabling netdev features down stack") Signed-off-by: Hauke Mehrtens Signed-off-by: David S. Miller --- include/linux/netdev_features.h | 23 +++++++++++++++++++++-- net/core/dev.c | 4 ++-- 2 files changed, 23 insertions(+), 4 deletions(-) (limited to 'net/core/dev.c') diff --git a/include/linux/netdev_features.h b/include/linux/netdev_features.h index 2b2a6dce1630..fce28562bed2 100644 --- a/include/linux/netdev_features.h +++ b/include/linux/netdev_features.h @@ -11,6 +11,7 @@ #define _LINUX_NETDEV_FEATURES_H #include +#include typedef u64 netdev_features_t; @@ -154,8 +155,26 @@ enum { #define NETIF_F_HW_TLS_TX __NETIF_F(HW_TLS_TX) #define NETIF_F_HW_TLS_RX __NETIF_F(HW_TLS_RX) -#define for_each_netdev_feature(mask_addr, bit) \ - for_each_set_bit(bit, (unsigned long *)mask_addr, NETDEV_FEATURE_COUNT) +/* Finds the next feature with the highest number of the range of start till 0. + */ +static inline int find_next_netdev_feature(u64 feature, unsigned long start) +{ + /* like BITMAP_LAST_WORD_MASK() for u64 + * this sets the most significant 64 - start to 0. + */ + feature &= ~0ULL >> (-start & ((sizeof(feature) * 8) - 1)); + + return fls64(feature) - 1; +} + +/* This goes for the MSB to the LSB through the set feature bits, + * mask_addr should be a u64 and bit an int + */ +#define for_each_netdev_feature(mask_addr, bit) \ + for ((bit) = find_next_netdev_feature((mask_addr), \ + NETDEV_FEATURE_COUNT); \ + (bit) >= 0; \ + (bit) = find_next_netdev_feature((mask_addr), (bit) - 1)) /* Features valid for ethtool to change */ /* = all defined minus driver/device-class-related */ diff --git a/net/core/dev.c b/net/core/dev.c index 8e276e0192a1..5d03889502eb 100644 --- a/net/core/dev.c +++ b/net/core/dev.c @@ -8152,7 +8152,7 @@ static netdev_features_t netdev_sync_upper_features(struct net_device *lower, netdev_features_t feature; int feature_bit; - for_each_netdev_feature(&upper_disables, feature_bit) { + for_each_netdev_feature(upper_disables, feature_bit) { feature = __NETIF_F_BIT(feature_bit); if (!(upper->wanted_features & feature) && (features & feature)) { @@ -8172,7 +8172,7 @@ static void netdev_sync_lower_features(struct net_device *upper, netdev_features_t feature; int feature_bit; - for_each_netdev_feature(&upper_disables, feature_bit) { + for_each_netdev_feature(upper_disables, feature_bit) { feature = __NETIF_F_BIT(feature_bit); if (!(features & feature) && (lower->features & feature)) { netdev_dbg(upper, "Disabling feature %pNF on lower dev %s.\n", -- cgit v1.2.3