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

net: ipconfig: move ic_nameservers_fallback into #ifdef block

2023-05-22T10:17:55+00:00

The new variable is only used when IPCONFIG_BOOTP is defined and otherwise causes a warning: net/ipv4/ipconfig.c:177:12: error: 'ic_nameservers_fallback' defined but not used [-Werror=unused-variable] Move it next to the user. Fixes: 81ac2722fa19 ("net: ipconfig: Allow DNS to be overwritten by DHCPACK") Signed-off-by: Arnd Bergmann Reviewed-by: Simon Horman Signed-off-by: David S. Miller

net: ipconfig: Allow DNS to be overwritten by DHCPACK

2023-05-10T08:20:47+00:00

Some DHCP server implementations only send the important requested DHCP options in the final BOOTP reply (DHCPACK). One example is systemd-networkd. However, RFC2131, in section 4.3.1 states: > The server MUST return to the client: > [...] > o Parameters requested by the client, according to the following > rules: > > -- IF the server has been explicitly configured with a default > value for the parameter, the server MUST include that value > in an appropriate option in the 'option' field, ELSE I've reported the issue here: https://github.com/systemd/systemd/issues/27471 Linux PNP DHCP client implementation only takes into account the DNS servers received in the first BOOTP reply (DHCPOFFER). This usually isn't an issue as servers are required to put the same values in the DHCPOFFER and DHCPACK. However, RFC2131, in section 4.3.2 states: > Any configuration parameters in the DHCPACK message SHOULD NOT > conflict with those in the earlier DHCPOFFER message to which the > client is responding. The client SHOULD use the parameters in the > DHCPACK message for configuration. When making Linux PNP DHCP client (cmdline ip=dhcp) interact with systemd-networkd DHCP server, an interesting "protocol misunderstanding" happens: Because DNS servers were only specified in the DHCPACK and not in the DHCPOFFER, Linux will not catch the correct DNS servers: in the first BOOTP reply (DHCPOFFER), it sees that there is no DNS, and sets as fallback the IP of the DHCP server itself. When the second BOOTP reply comes (DHCPACK), it's already too late: the kernel will not overwrite the fallback setting it has set previously. This patch makes the kernel overwrite its DNS fallback by DNS servers specified in the DHCPACK if any. Signed-off-by: Martin Wetterwald Signed-off-by: David S. Miller

Merge tag 'driver-core-6.0-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core

2022-08-04T18:31:20+00:00

Pull driver core / kernfs updates from Greg KH: "Here is the set of driver core and kernfs changes for 6.0-rc1. The "biggest" thing in here is some scalability improvements for kernfs for large systems. Other than that, included in here are: - arch topology and cache info changes that have been reviewed and discussed a lot. - potential error path cleanup fixes - deferred driver probe cleanups - firmware loader cleanups and tweaks - documentation updates - other small things All of these have been in the linux-next tree for a while with no reported problems" * tag 'driver-core-6.0-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (63 commits) docs: embargoed-hardware-issues: fix invalid AMD contact email firmware_loader: Replace kmap() with kmap_local_page() sysfs docs: ABI: Fix typo in comment kobject: fix Kconfig.debug "its" grammar kernfs: Fix typo 'the the' in comment docs: driver-api: firmware: add driver firmware guidelines. (v3) arch_topology: Fix cache attributes detection in the CPU hotplug path ACPI: PPTT: Leave the table mapped for the runtime usage cacheinfo: Use atomic allocation for percpu cache attributes drivers/base: fix userspace break from using bin_attributes for cpumap and cpulist MAINTAINERS: Change mentions of mpm to olivia docs: ABI: sysfs-devices-soc: Update Lee Jones' email address docs: ABI: sysfs-class-pwm: Update Lee Jones' email address Documentation/process: Add embargoed HW contact for LLVM Revert "kernfs: Change kernfs_notify_list to llist." ACPI: Remove the unused find_acpi_cpu_cache_topology() arch_topology: Warn that topology for nested clusters is not supported arch_topology: Add support for parsing sockets in /cpu-map arch_topology: Set cluster identifier in each core/thread from /cpu-map arch_topology: Limit span of cpu_clustergroup_mask() ...

net: ipconfig: use strscpy to replace strlcpy

2022-07-04T09:28:00+00:00

The strlcpy should not be used because it doesn't limit the source length. Preferred is strscpy. Signed-off-by: XueBing Chen Signed-off-by: David S. Miller

net: ipconfig: Relax fw_devlink if we need to mount a network rootfs

2022-06-10T13:57:54+00:00

If there are network devices that could probe without some of their suppliers probing and those network devices are needed to mount a network rootfs, then fw_devlink=on might break that usecase by blocking the network devices from probing by the time IP auto config starts. So, if no network devices are available when IP auto config is enabled and we have a network rootfs, make sure fw_devlink doesn't block the probing of any device that has a driver and then retry finding a network device. Tested-by: Geert Uytterhoeven Signed-off-by: Saravana Kannan Link: https://lore.kernel.org/r/20220601070707.3946847-6-saravanak@google.com Signed-off-by: Greg Kroah-Hartman

net: ipconfig: Release the rtnl_lock while waiting for carrier

2021-10-28T13:36:41+00:00

While waiting for a carrier to come on one of the netdevices, some devices will require to take the rtnl lock at some point to fully initialize all parts of the link. That's the case for SFP, where the rtnl is taken when a module gets detected. This prevents mounting an NFS rootfs over an SFP link. This means that while ipconfig waits for carriers to be detected, no SFP modules can be detected in the meantime, it's only detected after ipconfig times out. This commit releases the rtnl_lock while waiting for the carrier to come up, and re-takes it to check the for the init device and carrier status. Signed-off-by: Maxime Chevallier Signed-off-by: David S. Miller

net: ipconfig: Don't override command-line hostnames or domains

2021-06-02T20:27:03+00:00

If the user specifies a hostname or domain name as part of the ip= command-line option, preserve it and don't overwrite it with one supplied by DHCP/BOOTP. For instance, ip=::::myhostname::dhcp will use "myhostname" rather than ignoring and overwriting it. Fix the comment on ic_bootp_string that suggests it only copies a string "if not already set"; it doesn't have any such logic. Signed-off-by: Josh Triplett Signed-off-by: David S. Miller

net: ipconfig: ic_dev can be NULL in ic_close_devs

2021-03-22T19:57:51+00:00

ic_close_dev contains a generalization of the logic to not close a network interface if it's the host port for a DSA switch. This logic is disguised behind an iteration through the lowers of ic_dev in ic_close_dev. When no interface for ipconfig can be found, ic_dev is NULL, and ic_close_dev: - dereferences a NULL pointer when assigning selected_dev - would attempt to search through the lower interfaces of a NULL net_device pointer So we should protect against that case. The "lower_dev" iterator variable was shortened to "lower" in order to keep the 80 character limit. Fixes: f68cbaed67cb ("net: ipconfig: avoid use-after-free in ic_close_devs") Fixes: 46acf7bdbc72 ("Revert "net: ipv4: handle DSA enabled master network devices"") Signed-off-by: Vladimir Oltean Tested-by: Heiko Thiery Signed-off-by: David S. Miller

net: ipconfig: avoid use-after-free in ic_close_devs

2021-02-11T22:31:39+00:00

Due to the fact that ic_dev->dev is kept open in ic_close_dev, I had thought that ic_dev will not be freed either. But that is not the case, but instead "everybody dies" when ipconfig cleans up, and just the net_device behind ic_dev->dev remains allocated but not ic_dev itself. This is a problem because in ic_close_devs, for every net device that we're about to close, we compare it against the list of lower interfaces of ic_dev, to figure out whether we should close it or not. But since ic_dev itself is subject to freeing, this means that at some point in the middle of the list of ipconfig interfaces, ic_dev will have been freed, and we would be still attempting to iterate through its list of lower interfaces while checking whether to bring down the remaining ipconfig interfaces. There are multiple ways to avoid the use-after-free: we could delay freeing ic_dev until the very end (outside the while loop). Or an even simpler one: we can observe that we don't need ic_dev when iterating through its lowers, only ic_dev->dev, structure which isn't ever freed. So, by keeping ic_dev->dev in a variable assigned prior to freeing ic_dev, we can avoid all use-after-free issues. Fixes: 46acf7bdbc72 ("Revert "net: ipv4: handle DSA enabled master network devices"") Reported-by: kernel test robot Signed-off-by: Vladimir Oltean Reviewed-by: Florian Fainelli Signed-off-by: David S. Miller

Revert "net: ipv4: handle DSA enabled master network devices"

2021-02-06T22:42:57+00:00

This reverts commit 728c02089a0e3eefb02e9927bfae50490f40e72e. Since 2015 DSA has gained more integration with the network stack, we can now have the same functionality without explicitly open-coding for it: - It now opens the DSA master netdevice automatically whenever a user netdevice is opened. - The master and switch interfaces are coupled in an upper/lower hierarchy using the netdev adjacency lists. In the nfsroot example below, the interface chosen by autoconfig was swp3, and every interface except that and the DSA master, eth1, was brought down afterwards: [ 8.714215] mscc_felix 0000:00:00.5 swp0 (uninitialized): PHY [0000:00:00.3:10] driver [Microsemi GE VSC8514 SyncE] (irq=POLL) [ 8.978041] mscc_felix 0000:00:00.5 swp1 (uninitialized): PHY [0000:00:00.3:11] driver [Microsemi GE VSC8514 SyncE] (irq=POLL) [ 9.246134] mscc_felix 0000:00:00.5 swp2 (uninitialized): PHY [0000:00:00.3:12] driver [Microsemi GE VSC8514 SyncE] (irq=POLL) [ 9.486203] mscc_felix 0000:00:00.5 swp3 (uninitialized): PHY [0000:00:00.3:13] driver [Microsemi GE VSC8514 SyncE] (irq=POLL) [ 9.512827] mscc_felix 0000:00:00.5: configuring for fixed/internal link mode [ 9.521047] mscc_felix 0000:00:00.5: Link is Up - 2.5Gbps/Full - flow control off [ 9.530382] device eth1 entered promiscuous mode [ 9.535452] DSA: tree 0 setup [ 9.539777] printk: console [netcon0] enabled [ 9.544504] netconsole: network logging started [ 9.555047] fsl_enetc 0000:00:00.2 eth1: configuring for fixed/internal link mode [ 9.562790] fsl_enetc 0000:00:00.2 eth1: Link is Up - 1Gbps/Full - flow control off [ 9.564661] 8021q: adding VLAN 0 to HW filter on device bond0 [ 9.637681] fsl_enetc 0000:00:00.0 eth0: PHY [0000:00:00.0:02] driver [Qualcomm Atheros AR8031/AR8033] (irq=POLL) [ 9.655679] fsl_enetc 0000:00:00.0 eth0: configuring for inband/sgmii link mode [ 9.666611] mscc_felix 0000:00:00.5 swp0: configuring for inband/qsgmii link mode [ 9.676216] 8021q: adding VLAN 0 to HW filter on device swp0 [ 9.682086] mscc_felix 0000:00:00.5 swp1: configuring for inband/qsgmii link mode [ 9.690700] 8021q: adding VLAN 0 to HW filter on device swp1 [ 9.696538] mscc_felix 0000:00:00.5 swp2: configuring for inband/qsgmii link mode [ 9.705131] 8021q: adding VLAN 0 to HW filter on device swp2 [ 9.710964] mscc_felix 0000:00:00.5 swp3: configuring for inband/qsgmii link mode [ 9.719548] 8021q: adding VLAN 0 to HW filter on device swp3 [ 9.747811] Sending DHCP requests .. [ 12.742899] mscc_felix 0000:00:00.5 swp1: Link is Up - 1Gbps/Full - flow control rx/tx [ 12.743828] mscc_felix 0000:00:00.5 swp0: Link is Up - 1Gbps/Full - flow control off [ 12.747062] IPv6: ADDRCONF(NETDEV_CHANGE): swp1: link becomes ready [ 12.755216] fsl_enetc 0000:00:00.0 eth0: Link is Up - 1Gbps/Full - flow control rx/tx [ 12.766603] IPv6: ADDRCONF(NETDEV_CHANGE): swp0: link becomes ready [ 12.783188] mscc_felix 0000:00:00.5 swp2: Link is Up - 1Gbps/Full - flow control rx/tx [ 12.785354] IPv6: ADDRCONF(NETDEV_CHANGE): eth0: link becomes ready [ 12.799535] IPv6: ADDRCONF(NETDEV_CHANGE): swp2: link becomes ready [ 13.803141] mscc_felix 0000:00:00.5 swp3: Link is Up - 1Gbps/Full - flow control rx/tx [ 13.811646] IPv6: ADDRCONF(NETDEV_CHANGE): swp3: link becomes ready [ 15.452018] ., OK [ 15.470336] IP-Config: Got DHCP answer from 10.0.0.1, my address is 10.0.0.39 [ 15.477887] IP-Config: Complete: [ 15.481330] device=swp3, hwaddr=00:04:9f:05:de:0a, ipaddr=10.0.0.39, mask=255.255.255.0, gw=10.0.0.1 [ 15.491846] host=10.0.0.39, domain=(none), nis-domain=(none) [ 15.498429] bootserver=10.0.0.1, rootserver=10.0.0.1, rootpath= [ 15.498481] nameserver0=8.8.8.8 [ 15.627542] fsl_enetc 0000:00:00.0 eth0: Link is Down [ 15.690903] mscc_felix 0000:00:00.5 swp0: Link is Down [ 15.745216] mscc_felix 0000:00:00.5 swp1: Link is Down [ 15.800498] mscc_felix 0000:00:00.5 swp2: Link is Down Signed-off-by: Vladimir Oltean Reviewed-by: Andrew Lunn Reviewed-by: Florian Fainelli Signed-off-by: Jakub Kicinski