diff options
| author | Johannes Berg <johannes.berg@intel.com> | 2023-12-06 17:21:23 +0100 |
|---|---|---|
| committer | Jakub Kicinski <kuba@kernel.org> | 2023-12-08 16:10:17 -0800 |
| commit | bf17b36ccdd5b7b9dd482d7753bcb9aff2d21d39 (patch) | |
| tree | fad92655d8cc8204cd157a74d71bb68bcca71b5a /net/core/net-sysfs.c | |
| parent | 172db56d90d29e47e7d0d64885d5dbd92c87ec42 (diff) | |
net: sysfs: fix locking in carrier read
My previous patch added a call to linkwatch_sync_dev(),
but that of course needs to be called under RTNL, which
I missed earlier, but now saw RCU warnings from.
Fix that by acquiring the RTNL in a similar fashion to
how other files do it here.
Fixes: facd15dfd691 ("net: core: synchronize link-watch when carrier is queried")
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Link: https://lore.kernel.org/r/20231206172122.859df6ba937f.I9c80608bcfbab171943ff4942b52dbd5e97fe06e@changeid
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Diffstat (limited to 'net/core/net-sysfs.c')
| -rw-r--r-- | net/core/net-sysfs.c | 9 |
1 files changed, 7 insertions, 2 deletions
diff --git a/net/core/net-sysfs.c b/net/core/net-sysfs.c index d9b33e923b18..a09d507c5b03 100644 --- a/net/core/net-sysfs.c +++ b/net/core/net-sysfs.c @@ -193,6 +193,10 @@ static ssize_t carrier_show(struct device *dev, struct device_attribute *attr, char *buf) { struct net_device *netdev = to_net_dev(dev); + int ret = -EINVAL; + + if (!rtnl_trylock()) + return restart_syscall(); if (netif_running(netdev)) { /* Synchronize carrier state with link watch, @@ -200,10 +204,11 @@ static ssize_t carrier_show(struct device *dev, */ linkwatch_sync_dev(netdev); - return sysfs_emit(buf, fmt_dec, !!netif_carrier_ok(netdev)); + ret = sysfs_emit(buf, fmt_dec, !!netif_carrier_ok(netdev)); } + rtnl_unlock(); - return -EINVAL; + return ret; } static DEVICE_ATTR_RW(carrier); |