On Mon, Mar 17, 2025 at 12:24:19PM +0200, Mark Bloch wrote: > From: Mark Zhang <markzhang@xxxxxxxxxx> > > 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: > <TASK> > ? __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 > </TASK> > irq event stamp: 0 > hardirqs last enabled at (0): [<0000000000000000>] 0x0 > hardirqs last disabled at (0): [<ffffffff813f9e58>] copy_process+0xd08/0x2830 > softirqs last enabled at (0): [<ffffffff813f9e58>] 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 <markzhang@xxxxxxxxxx> > Reviewed-by: Maher Sanalla <msanalla@xxxxxxxxxx> > Signed-off-by: Mark Bloch <mbloch@xxxxxxxxxx> > --- > net/core/rtnetlink.c | 4 +++- > 1 file changed, 3 insertions(+), 1 deletion(-) > > diff --git a/net/core/rtnetlink.c b/net/core/rtnetlink.c > index d1e559fce918..bfc590e933d9 100644 > --- a/net/core/rtnetlink.c > +++ b/net/core/rtnetlink.c > @@ -1150,7 +1150,9 @@ static inline int rtnl_vfinfo_size(const struct net_device *dev, > nla_total_size(sizeof(struct ifla_vf_rate)) + > nla_total_size(sizeof(struct ifla_vf_link_state)) + > nla_total_size(sizeof(struct ifla_vf_rss_query_en)) + > - nla_total_size(sizeof(struct ifla_vf_trust))); > + nla_total_size(sizeof(struct ifla_vf_trust)) + > + (dev->netdev_ops->ndo_get_vf_guid ? > + nla_total_size(sizeof(struct ifla_vf_guid)) * 2 : 0)); > if (~ext_filter_mask & RTEXT_FILTER_SKIP_STATS) { > size += num_vfs * > (nla_total_size(0) + /* nest IFLA_VF_STATS */ Perhaps I'm over thinking things here, perhaps the following is easier on the eyes? diff --git a/net/core/rtnetlink.c b/net/core/rtnetlink.c index d1e559fce918..60fac848e092 100644 --- a/net/core/rtnetlink.c +++ b/net/core/rtnetlink.c @@ -1151,6 +1151,9 @@ static inline int rtnl_vfinfo_size(const struct net_device *dev, nla_total_size(sizeof(struct ifla_vf_link_state)) + nla_total_size(sizeof(struct ifla_vf_rss_query_en)) + nla_total_size(sizeof(struct ifla_vf_trust))); + if (dev->netdev_ops->ndo_get_vf_guid) + size += num_vfs * 2 * + nla_total_size(sizeof(struct ifla_vf_guid)); if (~ext_filter_mask & RTEXT_FILTER_SKIP_STATS) { size += num_vfs * (nla_total_size(0) + /* nest IFLA_VF_STATS */ In either case, the fix looks good to me. Reviewed-by: Simon Horman <horms@xxxxxxxxxx>