kernel/linux.git/net/core/rtnetlink.c, branch v5.10.257

rtnetlink: count IFLA_INFO_SLAVE_KIND in if_nlmsg_size

2026-04-18T08:31:04+00:00

[ Upstream commit ee00a12593ffb69db4dd1a1c00ecb0253376874a ] rtnl_link_get_slave_info_data_size counts IFLA_INFO_SLAVE_DATA, but rtnl_link_slave_info_fill adds both IFLA_INFO_SLAVE_DATA and IFLA_INFO_SLAVE_KIND. Fixes: ba7d49b1f0f8 ("rtnetlink: provide api for getting and setting slave info") Reviewed-by: Jiri Pirko Signed-off-by: Sabrina Dubroca Link: https://patch.msgid.link/049843b532e23cde7ddba263c0bbe35ba6f0d26d.1773919462.git.sd@queasysnail.net Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin

net: rtnetlink: fix module reference count leak issue in rtnetlink_rcv_msg

2025-10-29T13:01:25+00:00

commit 5b22f62724a0a09e00d301abf5b57b0c12be8a16 upstream. When bulk delete command is received in the rtnetlink_rcv_msg function, if bulk delete is not supported, module_put is not called to release the reference counting. As a result, module reference count is leaked. Fixes: a6cec0bcd342 ("net: rtnetlink: add bulk delete support flag") Signed-off-by: Zhengchao Shao Acked-by: Nikolay Aleksandrov Link: https://lore.kernel.org/r/20220815024629.240367-1-shaozhengchao@huawei.com Signed-off-by: Jakub Kicinski Signed-off-by: Greg Kroah-Hartman

rtnetlink: Allow deleting FDB entries in user namespace

2025-10-29T13:01:21+00:00

[ Upstream commit bf29555f5bdc017bac22ca66fcb6c9f46ec8788f ] Creating FDB entries is possible from a non-initial user namespace when having CAP_NET_ADMIN, yet, when deleting FDB entries, processes receive an EPERM because the capability is always checked against the initial user namespace. This restricts the FDB management from unprivileged containers. Drop the netlink_capable check in rtnl_fdb_del as it was originally dropped in c5c351088ae7 and reintroduced in 1690be63a27b without intention. This patch was tested using a container on GyroidOS, where it was possible to delete FDB entries from an unprivileged user namespace and private network namespace. Fixes: 1690be63a27b ("bridge: Add vlan support to static neighbors") Reviewed-by: Michael Weiß Tested-by: Harshal Gohel Signed-off-by: Johannes Wiesböck Reviewed-by: Ido Schimmel Reviewed-by: Nikolay Aleksandrov Link: https://patch.msgid.link/20251015201548.319871-1-johannes.wiesboeck@aisec.fraunhofer.de Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin

net: rtnetlink: add NLM_F_BULK support to rtnl_fdb_del

2025-10-29T13:01:21+00:00

[ Upstream commit 9e83425993f38bb89e0ea07849ba0039a748e85b ] When NLM_F_BULK is specified in a fdb del message we need to handle it differently. First since this is a new call we can strictly validate the passed attributes, at first only ifindex and vlan are allowed as these will be the initially supported filter attributes, any other attribute is rejected. The mac address is no longer mandatory, but we use it to error out in older kernels because it cannot be specified with bulk request (the attribute is not allowed) and then we have to dispatch the call to ndo_fdb_del_bulk if the device supports it. The del bulk callback can do further validation of the attributes if necessary. Signed-off-by: Nikolay Aleksandrov Signed-off-by: David S. Miller Stable-dep-of: bf29555f5bdc ("rtnetlink: Allow deleting FDB entries in user namespace") Signed-off-by: Sasha Levin

net: rtnetlink: add bulk delete support flag

2025-10-29T13:01:21+00:00

[ Upstream commit a6cec0bcd34264be8887791594be793b3f12719f ] Add a new rtnl flag (RTNL_FLAG_BULK_DEL_SUPPORTED) which is used to verify that the delete operation allows bulk object deletion. Also emit a warning if anyone tries to set it for non-delete kind. Suggested-by: David Ahern Signed-off-by: Nikolay Aleksandrov Signed-off-by: David S. Miller Stable-dep-of: bf29555f5bdc ("rtnetlink: Allow deleting FDB entries in user namespace") Signed-off-by: Sasha Levin

net: rtnetlink: add helper to extract msg type's kind

2025-10-29T13:01:21+00:00

[ Upstream commit 2e9ea3e30f696fd438319c07836422bb0bbb4608 ] Add a helper which extracts the msg type's kind using the kind mask (0x3). Signed-off-by: Nikolay Aleksandrov Signed-off-by: David S. Miller Stable-dep-of: bf29555f5bdc ("rtnetlink: Allow deleting FDB entries in user namespace") Signed-off-by: Sasha Levin

net: rtnetlink: add msg kind names

2025-10-29T13:01:21+00:00

[ Upstream commit 12dc5c2cb7b269c5a1c6d02844f40bfce942a7a6 ] Add rtnl kind names instead of using raw values. We'll need to check for DEL kind later to validate bulk flag support. Signed-off-by: Nikolay Aleksandrov Signed-off-by: David S. Miller Stable-dep-of: bf29555f5bdc ("rtnetlink: Allow deleting FDB entries in user namespace") Signed-off-by: Sasha Levin

rtnetlink: Allocate vfinfo size for VF GUIDs when supported

2025-04-10T12:30:59+00:00

[ Upstream commit 23f00807619d15063d676218f36c5dfeda1eb420 ] Commit 30aad41721e0 ("net/core: Add support for getting VF GUIDs") added support for getting VF port and node GUIDs in netlink ifinfo messages, but their size was not taken into consideration in the function that allocates the netlink message, causing the following warning when a netlink message is filled with many VF port and node GUIDs: # echo 64 > /sys/bus/pci/devices/0000\:08\:00.0/sriov_numvfs # ip link show dev ib0 RTNETLINK answers: Message too long Cannot send link get request: Message too long Kernel warning: ------------[ cut here ]------------ WARNING: CPU: 2 PID: 1930 at net/core/rtnetlink.c:4151 rtnl_getlink+0x586/0x5a0 Modules linked in: xt_conntrack xt_MASQUERADE nfnetlink xt_addrtype iptable_nat nf_nat br_netfilter overlay mlx5_ib macsec mlx5_core tls rpcrdma rdma_ucm ib_uverbs ib_iser libiscsi scsi_transport_iscsi ib_umad rdma_cm iw_cm ib_ipoib fuse ib_cm ib_core CPU: 2 UID: 0 PID: 1930 Comm: ip Not tainted 6.14.0-rc2+ #1 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.13.0-0-gf21b5a4aeb02-prebuilt.qemu.org 04/01/2014 RIP: 0010:rtnl_getlink+0x586/0x5a0 Code: cb 82 e8 3d af 0a 00 4d 85 ff 0f 84 08 ff ff ff 4c 89 ff 41 be ea ff ff ff e8 66 63 5b ff 49 c7 07 80 4f cb 82 e9 36 fc ff ff <0f> 0b e9 16 fe ff ff e8 de a0 56 00 66 66 2e 0f 1f 84 00 00 00 00 RSP: 0018:ffff888113557348 EFLAGS: 00010246 RAX: 00000000ffffffa6 RBX: ffff88817e87aa34 RCX: dffffc0000000000 RDX: 0000000000000003 RSI: 0000000000000000 RDI: ffff88817e87afb8 RBP: 0000000000000009 R08: ffffffff821f44aa R09: 0000000000000000 R10: ffff8881260f79a8 R11: ffff88817e87af00 R12: ffff88817e87aa00 R13: ffffffff8563d300 R14: 00000000ffffffa6 R15: 00000000ffffffff FS: 00007f63a5dbf280(0000) GS:ffff88881ee00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f63a5ba4493 CR3: 00000001700fe002 CR4: 0000000000772eb0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 PKRU: 55555554 Call Trace: ? __warn+0xa5/0x230 ? rtnl_getlink+0x586/0x5a0 ? report_bug+0x22d/0x240 ? handle_bug+0x53/0xa0 ? exc_invalid_op+0x14/0x50 ? asm_exc_invalid_op+0x16/0x20 ? skb_trim+0x6a/0x80 ? rtnl_getlink+0x586/0x5a0 ? __pfx_rtnl_getlink+0x10/0x10 ? rtnetlink_rcv_msg+0x1e5/0x860 ? __pfx___mutex_lock+0x10/0x10 ? rcu_is_watching+0x34/0x60 ? __pfx_lock_acquire+0x10/0x10 ? stack_trace_save+0x90/0xd0 ? filter_irq_stacks+0x1d/0x70 ? kasan_save_stack+0x30/0x40 ? kasan_save_stack+0x20/0x40 ? kasan_save_track+0x10/0x30 rtnetlink_rcv_msg+0x21c/0x860 ? entry_SYSCALL_64_after_hwframe+0x76/0x7e ? __pfx_rtnetlink_rcv_msg+0x10/0x10 ? arch_stack_walk+0x9e/0xf0 ? rcu_is_watching+0x34/0x60 ? lock_acquire+0xd5/0x410 ? rcu_is_watching+0x34/0x60 netlink_rcv_skb+0xe0/0x210 ? __pfx_rtnetlink_rcv_msg+0x10/0x10 ? __pfx_netlink_rcv_skb+0x10/0x10 ? rcu_is_watching+0x34/0x60 ? __pfx___netlink_lookup+0x10/0x10 ? lock_release+0x62/0x200 ? netlink_deliver_tap+0xfd/0x290 ? rcu_is_watching+0x34/0x60 ? lock_release+0x62/0x200 ? netlink_deliver_tap+0x95/0x290 netlink_unicast+0x31f/0x480 ? __pfx_netlink_unicast+0x10/0x10 ? rcu_is_watching+0x34/0x60 ? lock_acquire+0xd5/0x410 netlink_sendmsg+0x369/0x660 ? lock_release+0x62/0x200 ? __pfx_netlink_sendmsg+0x10/0x10 ? import_ubuf+0xb9/0xf0 ? __import_iovec+0x254/0x2b0 ? lock_release+0x62/0x200 ? __pfx_netlink_sendmsg+0x10/0x10 ____sys_sendmsg+0x559/0x5a0 ? __pfx_____sys_sendmsg+0x10/0x10 ? __pfx_copy_msghdr_from_user+0x10/0x10 ? rcu_is_watching+0x34/0x60 ? do_read_fault+0x213/0x4a0 ? rcu_is_watching+0x34/0x60 ___sys_sendmsg+0xe4/0x150 ? __pfx____sys_sendmsg+0x10/0x10 ? do_fault+0x2cc/0x6f0 ? handle_pte_fault+0x2e3/0x3d0 ? __pfx_handle_pte_fault+0x10/0x10 ? preempt_count_sub+0x14/0xc0 ? __down_read_trylock+0x150/0x270 ? __handle_mm_fault+0x404/0x8e0 ? __pfx___handle_mm_fault+0x10/0x10 ? lock_release+0x62/0x200 ? __rcu_read_unlock+0x65/0x90 ? rcu_is_watching+0x34/0x60 __sys_sendmsg+0xd5/0x150 ? __pfx___sys_sendmsg+0x10/0x10 ? __up_read+0x192/0x480 ? lock_release+0x62/0x200 ? __rcu_read_unlock+0x65/0x90 ? rcu_is_watching+0x34/0x60 do_syscall_64+0x6d/0x140 entry_SYSCALL_64_after_hwframe+0x76/0x7e RIP: 0033:0x7f63a5b13367 Code: 0e 00 f7 d8 64 89 02 48 c7 c0 ff ff ff ff eb b9 0f 1f 00 f3 0f 1e fa 64 8b 04 25 18 00 00 00 85 c0 75 10 b8 2e 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 51 c3 48 83 ec 28 89 54 24 1c 48 89 74 24 10 RSP: 002b:00007fff8c726bc8 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 0000000067b687c2 RCX: 00007f63a5b13367 RDX: 0000000000000000 RSI: 00007fff8c726c30 RDI: 0000000000000004 RBP: 00007fff8c726cb8 R08: 0000000000000000 R09: 0000000000000034 R10: 00007fff8c726c7c R11: 0000000000000246 R12: 0000000000000001 R13: 0000000000000000 R14: 00007fff8c726cd0 R15: 00007fff8c726cd0 irq event stamp: 0 hardirqs last enabled at (0): [<0000000000000000>] 0x0 hardirqs last disabled at (0): [] copy_process+0xd08/0x2830 softirqs last enabled at (0): [] copy_process+0xd08/0x2830 softirqs last disabled at (0): [<0000000000000000>] 0x0 ---[ end trace 0000000000000000 ]--- Thus, when calculating ifinfo message size, take VF GUIDs sizes into account when supported. Fixes: 30aad41721e0 ("net/core: Add support for getting VF GUIDs") Signed-off-by: Mark Zhang Reviewed-by: Maher Sanalla Signed-off-by: Mark Bloch Reviewed-by: Sabrina Dubroca Link: https://patch.msgid.link/20250325090226.749730-1-mbloch@nvidia.com Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin

rtnetlink: Correct nested IFLA_VF_VLAN_LIST attribute validation

2024-05-17T09:48:07+00:00

[ Upstream commit 1aec77b2bb2ed1db0f5efc61c4c1ca3813307489 ] Each attribute inside a nested IFLA_VF_VLAN_LIST is assumed to be a struct ifla_vf_vlan_info so the size of such attribute needs to be at least of sizeof(struct ifla_vf_vlan_info) which is 14 bytes. The current size validation in do_setvfinfo is against NLA_HDRLEN (4 bytes) which is less than sizeof(struct ifla_vf_vlan_info) so this validation is not enough and a too small attribute might be cast to a struct ifla_vf_vlan_info, this might result in an out of bands read access when accessing the saved (casted) entry in ivvl. Fixes: 79aab093a0b5 ("net: Update API for VF vlan protocol 802.1ad support") Signed-off-by: Roded Zats Reviewed-by: Donald Hunter Link: https://lore.kernel.org/r/20240502155751.75705-1-rzats@paloaltonetworks.com Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin

rtnetlink: fix error logic of IFLA_BRIDGE_FLAGS writing back

2024-03-06T14:37:49+00:00

[ Upstream commit 743ad091fb46e622f1b690385bb15e3cd3daf874 ] In the commit d73ef2d69c0d ("rtnetlink: let rtnl_bridge_setlink checks IFLA_BRIDGE_MODE length"), an adjustment was made to the old loop logic in the function `rtnl_bridge_setlink` to enable the loop to also check the length of the IFLA_BRIDGE_MODE attribute. However, this adjustment removed the `break` statement and led to an error logic of the flags writing back at the end of this function. if (have_flags) memcpy(nla_data(attr), &flags, sizeof(flags)); // attr should point to IFLA_BRIDGE_FLAGS NLA !!! Before the mentioned commit, the `attr` is granted to be IFLA_BRIDGE_FLAGS. However, this is not necessarily true fow now as the updated loop will let the attr point to the last NLA, even an invalid NLA which could cause overflow writes. This patch introduces a new variable `br_flag` to save the NLA pointer that points to IFLA_BRIDGE_FLAGS and uses it to resolve the mentioned error logic. Fixes: d73ef2d69c0d ("rtnetlink: let rtnl_bridge_setlink checks IFLA_BRIDGE_MODE length") Signed-off-by: Lin Ma Acked-by: Nikolay Aleksandrov Link: https://lore.kernel.org/r/20240227121128.608110-1-linma@zju.edu.cn Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin