Re: [PATCH] net: ethtool: fix unheld rtnl lock
From: Przemek Kitszel <przemyslaw.kitszel@intel.com>
Date: 2024-08-26 13:30:50
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linux-kernel-mentees, lkml
On 8/26/24 15:06, Diogo Jahchan Koike wrote:
ethnl_req_get_phydev should be called with rtnl lock held.
Next time please make use of more columns in commit message (75).
quoted hunk ↗ jump to hunk
Reported-by: syzbot+ec369e6d58e210135f71@syzkaller.appspotmail.com Closes: https://syzkaller.appspot.com/bug?extid=ec369e6d58e210135f71 Fixes: 31748765bed3 ("net: ethtool: pse-pd: Target the command to the requested PHY") Signed-off-by: Diogo Jahchan Koike <redacted> --- net/ethtool/pse-pd.c | 18 +++++++++++++----- 1 file changed, 13 insertions(+), 5 deletions(-)diff --git a/net/ethtool/pse-pd.c b/net/ethtool/pse-pd.c index 507cb21d6bf0..290edbfd47d2 100644 --- a/net/ethtool/pse-pd.c +++ b/net/ethtool/pse-pd.c@@ -226,17 +226,21 @@ ethnl_set_pse_validate(struct ethnl_req_info *req_info, struct genl_info *info) { struct nlattr **tb = info->attrs; struct phy_device *phydev; + int ret = 1; + rtnl_lock(); phydev = ethnl_req_get_phydev(req_info, tb[ETHTOOL_A_PSE_HEADER], info->extack);
Fix looks fine, thanks, I will however unlock just after ethnl_req_get_phydev() call. Then all ret code logic touches could be omitted.
quoted hunk ↗ jump to hunk
if (IS_ERR_OR_NULL(phydev)) { NL_SET_ERR_MSG(info->extack, "No PHY is attached"); - return -EOPNOTSUPP; + ret = -EOPNOTSUPP; + goto out; } if (!phydev->psec) { NL_SET_ERR_MSG(info->extack, "No PSE is attached"); - return -EOPNOTSUPP; + ret = -EOPNOTSUPP; + goto out; } if (tb[ETHTOOL_A_PODL_PSE_ADMIN_CONTROL] &&@@ -244,17 +248,21 @@ ethnl_set_pse_validate(struct ethnl_req_info *req_info, struct genl_info *info) NL_SET_ERR_MSG_ATTR(info->extack, tb[ETHTOOL_A_PODL_PSE_ADMIN_CONTROL], "setting PoDL PSE admin control not supported"); - return -EOPNOTSUPP; + ret = -EOPNOTSUPP; + goto out; } if (tb[ETHTOOL_A_C33_PSE_ADMIN_CONTROL] && !pse_has_c33(phydev->psec)) { NL_SET_ERR_MSG_ATTR(info->extack, tb[ETHTOOL_A_C33_PSE_ADMIN_CONTROL], "setting C33 PSE admin control not supported"); - return -EOPNOTSUPP; + ret = -EOPNOTSUPP; + goto out; } - return 1; +out: + rtnl_unlock(); + return ret; } static int