| From f2847aa712f0534fb0dd6b944bb3cf1097500f33 Mon Sep 17 00:00:00 2001 |
| From: Sasha Levin <sashal@kernel.org> |
| Date: Thu, 15 Dec 2022 20:41:22 -0800 |
| Subject: devlink: protect devlink dump by the instance lock |
| |
| From: Jakub Kicinski <kuba@kernel.org> |
| |
| [ Upstream commit 214964a13ab56a9757d146b79b468a7ca190fbfb ] |
| |
| Take the instance lock around devlink_nl_fill() when dumping, |
| doit takes it already. |
| |
| We are only dumping basic info so in the worst case we were risking |
| data races around the reload statistics. Until the big devlink mutex |
| was removed all relevant code was protected by it, so the missing |
| instance lock was not exposed. |
| |
| Fixes: d3efc2a6a6d8 ("net: devlink: remove devlink_mutex") |
| Reviewed-by: Jiri Pirko <jiri@nvidia.com> |
| Reviewed-by: Jacob Keller <jacob.e.keller@intel.com> |
| Link: https://lore.kernel.org/r/20221216044122.1863550-1-kuba@kernel.org |
| Signed-off-by: Jakub Kicinski <kuba@kernel.org> |
| Signed-off-by: Sasha Levin <sashal@kernel.org> |
| --- |
| net/core/devlink.c | 3 +++ |
| 1 file changed, 3 insertions(+) |
| |
| diff --git a/net/core/devlink.c b/net/core/devlink.c |
| index b3a869ccc8ed..5f894bd20c31 100644 |
| --- a/net/core/devlink.c |
| +++ b/net/core/devlink.c |
| @@ -1498,10 +1498,13 @@ static int devlink_nl_cmd_get_dumpit(struct sk_buff *msg, |
| continue; |
| } |
| |
| + devl_lock(devlink); |
| err = devlink_nl_fill(msg, devlink, DEVLINK_CMD_NEW, |
| NETLINK_CB(cb->skb).portid, |
| cb->nlh->nlmsg_seq, NLM_F_MULTI); |
| + devl_unlock(devlink); |
| devlink_put(devlink); |
| + |
| if (err) |
| goto out; |
| idx++; |
| -- |
| 2.35.1 |
| |
