From 979b581e4c69257acab1af415ddad6b2d78a2fa5 Mon Sep 17 00:00:00 2001 From: Eric Dumazet Date: Wed, 21 Aug 2024 17:53:39 +0000 Subject: pktgen: use cpus_read_lock() in pg_net_init() I have seen the WARN_ON(smp_processor_id() != cpu) firing in pktgen_thread_worker() during tests. We must use cpus_read_lock()/cpus_read_unlock() around the for_each_online_cpu(cpu) loop. While we are at it use WARN_ON_ONCE() to avoid a possible syslog flood. Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: Eric Dumazet Link: https://patch.msgid.link/20240821175339.1191779-1-edumazet@google.com Signed-off-by: Jakub Kicinski --- net/core/pktgen.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) (limited to 'net/core') diff --git a/net/core/pktgen.c b/net/core/pktgen.c index ea55a758a475..197a50ef8e2e 100644 --- a/net/core/pktgen.c +++ b/net/core/pktgen.c @@ -3654,7 +3654,7 @@ static int pktgen_thread_worker(void *arg) struct pktgen_dev *pkt_dev = NULL; int cpu = t->cpu; - WARN_ON(smp_processor_id() != cpu); + WARN_ON_ONCE(smp_processor_id() != cpu); init_waitqueue_head(&t->queue); complete(&t->start_done); @@ -3989,6 +3989,7 @@ static int __net_init pg_net_init(struct net *net) goto remove; } + cpus_read_lock(); for_each_online_cpu(cpu) { int err; @@ -3997,6 +3998,7 @@ static int __net_init pg_net_init(struct net *net) pr_warn("Cannot create thread for cpu %d (%d)\n", cpu, err); } + cpus_read_unlock(); if (list_empty(&pn->pktgen_threads)) { pr_err("Initialization failed for all threads\n"); -- cgit v1.2.3-58-ga151 From a699781c79ecf6cfe67fb00a0331b4088c7c8466 Mon Sep 17 00:00:00 2001 From: Jamie Bainbridge Date: Fri, 23 Aug 2024 16:26:58 +1000 Subject: ethtool: check device is present when getting link settings A sysfs reader can race with a device reset or removal, attempting to read device state when the device is not actually present. eg: [exception RIP: qed_get_current_link+17] #8 [ffffb9e4f2907c48] qede_get_link_ksettings at ffffffffc07a994a [qede] #9 [ffffb9e4f2907cd8] __rh_call_get_link_ksettings at ffffffff992b01a3 #10 [ffffb9e4f2907d38] __ethtool_get_link_ksettings at ffffffff992b04e4 #11 [ffffb9e4f2907d90] duplex_show at ffffffff99260300 #12 [ffffb9e4f2907e38] dev_attr_show at ffffffff9905a01c #13 [ffffb9e4f2907e50] sysfs_kf_seq_show at ffffffff98e0145b #14 [ffffb9e4f2907e68] seq_read at ffffffff98d902e3 #15 [ffffb9e4f2907ec8] vfs_read at ffffffff98d657d1 #16 [ffffb9e4f2907f00] ksys_read at ffffffff98d65c3f #17 [ffffb9e4f2907f38] do_syscall_64 at ffffffff98a052fb crash> struct net_device.state ffff9a9d21336000 state = 5, state 5 is __LINK_STATE_START (0b1) and __LINK_STATE_NOCARRIER (0b100). The device is not present, note lack of __LINK_STATE_PRESENT (0b10). This is the same sort of panic as observed in commit 4224cfd7fb65 ("net-sysfs: add check for netdevice being present to speed_show"). There are many other callers of __ethtool_get_link_ksettings() which don't have a device presence check. Move this check into ethtool to protect all callers. Fixes: d519e17e2d01 ("net: export device speed and duplex via sysfs") Fixes: 4224cfd7fb65 ("net-sysfs: add check for netdevice being present to speed_show") Signed-off-by: Jamie Bainbridge Link: https://patch.msgid.link/8bae218864beaa44ed01628140475b9bf641c5b0.1724393671.git.jamie.bainbridge@gmail.com Signed-off-by: Jakub Kicinski --- net/core/net-sysfs.c | 2 +- net/ethtool/ioctl.c | 3 +++ 2 files changed, 4 insertions(+), 1 deletion(-) (limited to 'net/core') diff --git a/net/core/net-sysfs.c b/net/core/net-sysfs.c index 0e2084ce7b75..444f23e74f8e 100644 --- a/net/core/net-sysfs.c +++ b/net/core/net-sysfs.c @@ -235,7 +235,7 @@ static ssize_t speed_show(struct device *dev, if (!rtnl_trylock()) return restart_syscall(); - if (netif_running(netdev) && netif_device_present(netdev)) { + if (netif_running(netdev)) { struct ethtool_link_ksettings cmd; if (!__ethtool_get_link_ksettings(netdev, &cmd)) diff --git a/net/ethtool/ioctl.c b/net/ethtool/ioctl.c index e18823bf2330..ae041f51cd2d 100644 --- a/net/ethtool/ioctl.c +++ b/net/ethtool/ioctl.c @@ -442,6 +442,9 @@ int __ethtool_get_link_ksettings(struct net_device *dev, if (!dev->ethtool_ops->get_link_ksettings) return -EOPNOTSUPP; + if (!netif_device_present(dev)) + return -ENODEV; + memset(link_ksettings, 0, sizeof(*link_ksettings)); return dev->ethtool_ops->get_link_ksettings(dev, link_ksettings); } -- cgit v1.2.3-58-ga151