From 50bf398e1ceacb9a7f85bd3bdca065ebe5cb6159 Mon Sep 17 00:00:00 2001 From: Jakub Kicinski Date: Wed, 22 Jan 2025 14:45:03 -0800 Subject: net: netdevsim: try to close UDP port harness races syzbot discovered that we remove the debugfs files after we free the netdev. Try to clean up the relevant dir while the device is still around. Reported-by: syzbot+2e5de9e3ab986b71d2bf@syzkaller.appspotmail.com Fixes: 424be63ad831 ("netdevsim: add UDP tunnel port offload support") Reviewed-by: Michal Swiatkowski Link: https://patch.msgid.link/20250122224503.762705-1-kuba@kernel.org Signed-off-by: Jakub Kicinski --- drivers/net/netdevsim/netdevsim.h | 1 + drivers/net/netdevsim/udp_tunnels.c | 23 ++++++++++++++--------- 2 files changed, 15 insertions(+), 9 deletions(-) (limited to 'drivers/net/netdevsim') diff --git a/drivers/net/netdevsim/netdevsim.h b/drivers/net/netdevsim/netdevsim.h index dcf073bc4802..96d54c08043d 100644 --- a/drivers/net/netdevsim/netdevsim.h +++ b/drivers/net/netdevsim/netdevsim.h @@ -134,6 +134,7 @@ struct netdevsim { u32 sleep; u32 __ports[2][NSIM_UDP_TUNNEL_N_PORTS]; u32 (*ports)[NSIM_UDP_TUNNEL_N_PORTS]; + struct dentry *ddir; struct debugfs_u32_array dfs_ports[2]; } udp_ports; diff --git a/drivers/net/netdevsim/udp_tunnels.c b/drivers/net/netdevsim/udp_tunnels.c index 02dc3123eb6c..640b4983a9a0 100644 --- a/drivers/net/netdevsim/udp_tunnels.c +++ b/drivers/net/netdevsim/udp_tunnels.c @@ -112,9 +112,11 @@ nsim_udp_tunnels_info_reset_write(struct file *file, const char __user *data, struct net_device *dev = file->private_data; struct netdevsim *ns = netdev_priv(dev); - memset(ns->udp_ports.ports, 0, sizeof(ns->udp_ports.__ports)); rtnl_lock(); - udp_tunnel_nic_reset_ntf(dev); + if (dev->reg_state == NETREG_REGISTERED) { + memset(ns->udp_ports.ports, 0, sizeof(ns->udp_ports.__ports)); + udp_tunnel_nic_reset_ntf(dev); + } rtnl_unlock(); return count; @@ -144,23 +146,23 @@ int nsim_udp_tunnels_info_create(struct nsim_dev *nsim_dev, else ns->udp_ports.ports = nsim_dev->udp_ports.__ports; - debugfs_create_u32("udp_ports_inject_error", 0600, - ns->nsim_dev_port->ddir, + ns->udp_ports.ddir = debugfs_create_dir("udp_ports", + ns->nsim_dev_port->ddir); + + debugfs_create_u32("inject_error", 0600, ns->udp_ports.ddir, &ns->udp_ports.inject_error); ns->udp_ports.dfs_ports[0].array = ns->udp_ports.ports[0]; ns->udp_ports.dfs_ports[0].n_elements = NSIM_UDP_TUNNEL_N_PORTS; - debugfs_create_u32_array("udp_ports_table0", 0400, - ns->nsim_dev_port->ddir, + debugfs_create_u32_array("table0", 0400, ns->udp_ports.ddir, &ns->udp_ports.dfs_ports[0]); ns->udp_ports.dfs_ports[1].array = ns->udp_ports.ports[1]; ns->udp_ports.dfs_ports[1].n_elements = NSIM_UDP_TUNNEL_N_PORTS; - debugfs_create_u32_array("udp_ports_table1", 0400, - ns->nsim_dev_port->ddir, + debugfs_create_u32_array("table1", 0400, ns->udp_ports.ddir, &ns->udp_ports.dfs_ports[1]); - debugfs_create_file("udp_ports_reset", 0200, ns->nsim_dev_port->ddir, + debugfs_create_file("reset", 0200, ns->udp_ports.ddir, dev, &nsim_udp_tunnels_info_reset_fops); /* Note: it's not normal to allocate the info struct like this! @@ -196,6 +198,9 @@ int nsim_udp_tunnels_info_create(struct nsim_dev *nsim_dev, void nsim_udp_tunnels_info_destroy(struct net_device *dev) { + struct netdevsim *ns = netdev_priv(dev); + + debugfs_remove_recursive(ns->udp_ports.ddir); kfree(dev->udp_tunnel_nic_info); dev->udp_tunnel_nic_info = NULL; } -- cgit v1.2.3 From 6db9d3a536cd638e2ee17cf880e14026cec19d26 Mon Sep 17 00:00:00 2001 From: Jakub Kicinski Date: Thu, 23 Jan 2025 14:14:10 -0800 Subject: netdevsim: don't assume core pre-populates HDS params on GET Syzbot reports: BUG: KMSAN: uninit-value in nsim_get_ringparam+0xa8/0xe0 drivers/net/netdevsim/ethtool.c:77 nsim_get_ringparam+0xa8/0xe0 drivers/net/netdevsim/ethtool.c:77 ethtool_set_ringparam+0x268/0x570 net/ethtool/ioctl.c:2072 __dev_ethtool net/ethtool/ioctl.c:3209 [inline] dev_ethtool+0x126d/0x2a40 net/ethtool/ioctl.c:3398 dev_ioctl+0xb0e/0x1280 net/core/dev_ioctl.c:759 This is the SET path, where we call GET to either check user request against max values, or check if any of the settings will change. The logic in netdevsim is trying to report the default (ENABLED) if user has not requested any specific setting. The user setting is recorded in dev->cfg, don't depend on kernel_ringparam being pre-populated with it. Fixes: 928459bbda19 ("net: ethtool: populate the default HDS params in the core") Reported-by: Eric Dumazet Reported-by: syzbot+b3bcd80232d00091e061@syzkaller.appspotmail.com Tested-by: syzbot+b3bcd80232d00091e061@syzkaller.appspotmail.com Link: https://patch.msgid.link/20250123221410.1067678-1-kuba@kernel.org Signed-off-by: Jakub Kicinski --- drivers/net/netdevsim/ethtool.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'drivers/net/netdevsim') diff --git a/drivers/net/netdevsim/ethtool.c b/drivers/net/netdevsim/ethtool.c index 3b23f3d3ca2b..5c80fbee7913 100644 --- a/drivers/net/netdevsim/ethtool.c +++ b/drivers/net/netdevsim/ethtool.c @@ -74,7 +74,7 @@ static void nsim_get_ringparam(struct net_device *dev, memcpy(ring, &ns->ethtool.ring, sizeof(ns->ethtool.ring)); kernel_ring->hds_thresh_max = NSIM_HDS_THRESHOLD_MAX; - if (kernel_ring->tcp_data_split == ETHTOOL_TCP_DATA_SPLIT_UNKNOWN) + if (dev->cfg->hds_config == ETHTOOL_TCP_DATA_SPLIT_UNKNOWN) kernel_ring->tcp_data_split = ETHTOOL_TCP_DATA_SPLIT_ENABLED; } -- cgit v1.2.3