| Message ID | 20200320234650.E3383E0FD3@unicorn.suse.cz |
|---|---|
| State | Accepted |
| Delegated to: | David Miller |
| Headers | show |
| Series | [net,v2] netlink: check for null extack in cookie helpers | expand |
From: Michal Kubecek <mkubecek@suse.cz> Date: Sat, 21 Mar 2020 00:46:50 +0100 (CET) > Unlike NL_SET_ERR_* macros, nl_set_extack_cookie_u64() and > nl_set_extack_cookie_u32() helpers do not check extack argument for null > and neither do their callers, as syzbot recently discovered for > ethnl_parse_header(). > > Instead of fixing the callers and leaving the trap in place, add check of > null extack to both helpers to make them consistent with NL_SET_ERR_* > macros. > > v2: drop incorrect second Fixes tag > > Fixes: 2363d73a2f3e ("ethtool: reject unrecognized request flags") > Reported-by: syzbot+258a9089477493cea67b@syzkaller.appspotmail.com > Signed-off-by: Michal Kubecek <mkubecek@suse.cz> Applied, thanks Michal.
diff --git a/include/linux/netlink.h b/include/linux/netlink.h index 4090524c3462..60739d0cbf93 100644 --- a/include/linux/netlink.h +++ b/include/linux/netlink.h @@ -115,6 +115,8 @@ static inline void nl_set_extack_cookie_u64(struct netlink_ext_ack *extack, { u64 __cookie = cookie; + if (!extack) + return; memcpy(extack->cookie, &__cookie, sizeof(__cookie)); extack->cookie_len = sizeof(__cookie); } @@ -124,6 +126,8 @@ static inline void nl_set_extack_cookie_u32(struct netlink_ext_ack *extack, { u32 __cookie = cookie; + if (!extack) + return; memcpy(extack->cookie, &__cookie, sizeof(__cookie)); extack->cookie_len = sizeof(__cookie); }
Unlike NL_SET_ERR_* macros, nl_set_extack_cookie_u64() and nl_set_extack_cookie_u32() helpers do not check extack argument for null and neither do their callers, as syzbot recently discovered for ethnl_parse_header(). Instead of fixing the callers and leaving the trap in place, add check of null extack to both helpers to make them consistent with NL_SET_ERR_* macros. v2: drop incorrect second Fixes tag Fixes: 2363d73a2f3e ("ethtool: reject unrecognized request flags") Reported-by: syzbot+258a9089477493cea67b@syzkaller.appspotmail.com Signed-off-by: Michal Kubecek <mkubecek@suse.cz> --- include/linux/netlink.h | 4 ++++ 1 file changed, 4 insertions(+)