kernel/linux.git/net/ipv4/devinet.c, branch v6.6.131

ipv4: Fix NULL vs error pointer check in inet_blackhole_dev_init()

2025-09-09T16:56:24+00:00

[ Upstream commit a51160f8da850a65afbf165f5bbac7ffb388bf74 ] The inetdev_init() function never returns NULL. Check for error pointers instead. Fixes: 22600596b675 ("ipv4: give an IPv4 dev to blackhole_netdev") Signed-off-by: Dan Carpenter Reviewed-by: Simon Horman Reviewed-by: Eric Dumazet Link: https://patch.msgid.link/aLaQWL9NguWmeM1i@stanley.mountain Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin

ipv4: use RCU protection in inet_select_addr()

2025-02-21T12:57:20+00:00

[ Upstream commit 719817cd293e4fa389e1f69c396f3f816ed5aa41 ] inet_select_addr() must use RCU protection to make sure the net structure it reads does not disappear. Fixes: c4544c724322 ("[NETNS]: Process inet_select_addr inside a namespace.") Signed-off-by: Eric Dumazet Link: https://patch.msgid.link/20250205155120.1676781-7-edumazet@google.com Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin

ipv4: give an IPv4 dev to blackhole_netdev

2024-11-01T00:58:20+00:00

[ Upstream commit 22600596b6756b166fd052d5facb66287e6f0bad ] After commit 8d7017fd621d ("blackhole_netdev: use blackhole_netdev to invalidate dst entries"), blackhole_netdev was introduced to invalidate dst cache entries on the TX path whenever the cache times out or is flushed. When two UDP sockets (sk1 and sk2) send messages to the same destination simultaneously, they are using the same dst cache. If the dst cache is invalidated on one path (sk2) while the other (sk1) is still transmitting, sk1 may try to use the invalid dst entry. CPU1 CPU2 udp_sendmsg(sk1) udp_sendmsg(sk2) udp_send_skb() ip_output() <--- dst timeout or flushed dst_dev_put() ip_finish_output2() ip_neigh_for_gw() This results in a scenario where ip_neigh_for_gw() returns -EINVAL because blackhole_dev lacks an in_dev, which is needed to initialize the neigh in arp_constructor(). This error is then propagated back to userspace, breaking the UDP application. The patch fixes this issue by assigning an in_dev to blackhole_dev for IPv4, similar to what was done for IPv6 in commit e5f80fcf869a ("ipv6: give an IPv6 dev to blackhole_netdev"). This ensures that even when the dst entry is invalidated with blackhole_dev, it will not fail to create the neigh entry. As devinet_init() is called ealier than blackhole_netdev_init() in system booting, it can not assign the in_dev to blackhole_dev in devinet_init(). As Paolo suggested, add a separate late_initcall() in devinet.c to ensure inet_blackhole_dev_init() is called after blackhole_netdev_init(). Fixes: 8d7017fd621d ("blackhole_netdev: use blackhole_netdev to invalidate dst entries") Signed-off-by: Xin Long Reviewed-by: Eric Dumazet Link: https://patch.msgid.link/3000792d45ca44e16c785ebe2b092e610e5b3df1.1728499633.git.lucien.xin@gmail.com Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin

ipv4: Check !in_dev earlier for ioctl(SIOCSIFADDR).

2024-10-10T09:57:26+00:00

[ Upstream commit e3af3d3c5b26c33a7950e34e137584f6056c4319 ] dev->ip_ptr could be NULL if we set an invalid MTU. Even then, if we issue ioctl(SIOCSIFADDR) for a new IPv4 address, devinet_ioctl() allocates struct in_ifaddr and fails later in inet_set_ifa() because in_dev is NULL. Let's move the check earlier. Signed-off-by: Kuniyuki Iwashima Link: https://patch.msgid.link/20240809235406.50187-2-kuniyu@amazon.com Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin

ipv4: properly combine dev_base_seq and ipv4.dev_addr_genid

2024-03-01T12:35:07+00:00

[ Upstream commit 081a0e3b0d4c061419d3f4679dec9f68725b17e4 ] net->dev_base_seq and ipv4.dev_addr_genid are monotonically increasing. If we XOR their values, we could miss to detect if both values were changed with the same amount. Fixes: 0465277f6b3f ("ipv4: provide addr and netconf dump consistency info") Signed-off-by: Eric Dumazet Cc: Nicolas Dichtel Acked-by: Nicolas Dichtel Signed-off-by: David S. Miller Signed-off-by: Sasha Levin

net: ipv4: fix one memleak in __inet_del_ifa()

2023-09-08T07:02:17+00:00

I got the below warning when do fuzzing test: unregister_netdevice: waiting for bond0 to become free. Usage count = 2 It can be repoduced via: ip link add bond0 type bond sysctl -w net.ipv4.conf.bond0.promote_secondaries=1 ip addr add 4.117.174.103/0 scope 0x40 dev bond0 ip addr add 192.168.100.111/255.255.255.254 scope 0 dev bond0 ip addr add 0.0.0.4/0 scope 0x40 secondary dev bond0 ip addr del 4.117.174.103/0 scope 0x40 dev bond0 ip link delete bond0 type bond In this reproduction test case, an incorrect 'last_prim' is found in __inet_del_ifa(), as a result, the secondary address(0.0.0.4/0 scope 0x40) is lost. The memory of the secondary address is leaked and the reference of in_device and net_device is leaked. Fix this problem: Look for 'last_prim' starting at location of the deleted IP and inserting the promoted IP into the location of 'last_prim'. Fixes: 0ff60a45678e ("[IPV4]: Fix secondary IP addresses after promotion") Signed-off-by: Liu Jian Signed-off-by: Julian Anastasov Signed-off-by: David S. Miller

Merge tag 'sysctl-6.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/mcgrof/linux

2023-08-30T00:39:15+00:00

Pull sysctl updates from Luis Chamberlain: "Long ago we set out to remove the kitchen sink on kernel/sysctl.c arrays and placings sysctls to their own sybsystem or file to help avoid merge conflicts. Matthew Wilcox pointed out though that if we're going to do that we might as well also *save* space while at it and try to remove the extra last sysctl entry added at the end of each array, a sentintel, instead of bloating the kernel by adding a new sentinel with each array moved. Doing that was not so trivial, and has required slowing down the moves of kernel/sysctl.c arrays and measuring the impact on size by each new move. The complex part of the effort to help reduce the size of each sysctl is being done by the patient work of el señor Don Joel Granados. A lot of this is truly painful code refactoring and testing and then trying to measure the savings of each move and removing the sentinels. Although Joel already has code which does most of this work, experience with sysctl moves in the past shows is we need to be careful due to the slew of odd build failures that are possible due to the amount of random Kconfig options sysctls use. To that end Joel's work is split by first addressing the major housekeeping needed to remove the sentinels, which is part of this merge request. The rest of the work to actually remove the sentinels will be done later in future kernel releases. The preliminary math is showing this will all help reduce the overall build time size of the kernel and run time memory consumed by the kernel by about ~64 bytes per array where we are able to remove each sentinel in the future. That also means there is no more bloating the kernel with the extra ~64 bytes per array moved as no new sentinels are created" * tag 'sysctl-6.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/mcgrof/linux: sysctl: Use ctl_table_size as stopping criteria for list macro sysctl: SIZE_MAX->ARRAY_SIZE in register_net_sysctl vrf: Update to register_net_sysctl_sz networking: Update to register_net_sysctl_sz netfilter: Update to register_net_sysctl_sz ax.25: Update to register_net_sysctl_sz sysctl: Add size to register_net_sysctl function sysctl: Add size arg to __register_sysctl_init sysctl: Add size to register_sysctl sysctl: Add a size arg to __register_sysctl_table sysctl: Add size argument to init_header sysctl: Add ctl_table_size to ctl_table_header sysctl: Use ctl_table_header in list_for_each_table_entry sysctl: Prefer ctl_table_header in proc_sysctl

IPv4: add extack info for IPv4 address add/delete

2023-08-21T06:35:59+00:00

Add extack info for IPv4 address add/delete, which would be useful for users to understand the problem without having to read kernel code. No extack message for the ifa_local checking in __inet_insert_ifa() as it has been checked in find_matching_ifa(). Suggested-by: Ido Schimmel Signed-off-by: Hangbin Liu Reviewed-by: David Ahern Reviewed-by: Ido Schimmel Signed-off-by: David S. Miller

networking: Update to register_net_sysctl_sz

2023-08-15T22:26:18+00:00

Move from register_net_sysctl to register_net_sysctl_sz for all the networking related files. Do this while making sure to mirror the NULL assignments with a table_size of zero for the unprivileged users. We need to move to the new function in preparation for when we change SIZE_MAX to ARRAY_SIZE() in the register_net_sysctl macro. Failing to do so would erroneously allow ARRAY_SIZE() to be called on a pointer. We hold off the SIZE_MAX to ARRAY_SIZE change until we have migrated all the relevant net sysctl registering functions to register_net_sysctl_sz in subsequent commits. An additional size function was added to the following files in order to calculate the size of an array that is defined in another file: include/net/ipv6.h net/ipv6/icmp.c net/ipv6/route.c net/ipv6/sysctl_net_ipv6.c Signed-off-by: Joel Granados Signed-off-by: Luis Chamberlain

net: ipv4: Allow changing IPv4 address protocol

2023-03-23T08:32:52+00:00

When IP address protocol field was added in commit 47f0bd503210 ("net: Add new protocol attribute to IP addresses"), the semantics included the ability to change the protocol for IPv6 addresses, but not for IPv4 addresses. It seems this was not deliberate, but rather by accident. A userspace that wants to change the protocol of an address might drop and recreate the address, but that disrupts routing and is just impractical. So in this patch, when an IPv4 address is replaced (through RTM_NEWADDR request with NLM_F_REPLACE flag), update the proto at the address to the one given in the request, or zero if none is given. This matches the behavior of IPv6. Previously, any new value given was simply ignored. Signed-off-by: Petr Machata Reviewed-by: Ido Schimmel Reviewed-by: David Ahern Signed-off-by: David S. Miller