Currently there are no strict checks while setting SO_TXTIME from userspace. With the recent development in skb->tstamp_type clockid with unsupported clocks results in warn_on_once, which causes unnecessary aborts in some systems which enables panic on warns. Add validation in setsockopt to support only CLOCK_REALTIME, CLOCK_MONOTONIC and CLOCK_TAI to be set from userspace. Link: https://lore.kernel.org/netdev/bc037db4-58bb-4861-ac31-a361a93841d3@xxxxxxxxx/ Link: https://lore.kernel.org/lkml/6bdba7b6-fd22-4ea5-a356-12268674def1@xxxxxxxxxxx/ Fixes: 1693c5db6ab8 ("net: Add additional bit to support clockid_t timestamp type") Reported-by: syzbot+d7b227731ec589e7f4f0@xxxxxxxxxxxxxxxxxxxxxxxxx Closes: https://syzkaller.appspot.com/bug?extid=d7b227731ec589e7f4f0 Reported-by: syzbot+30a35a2e9c5067cc43fa@xxxxxxxxxxxxxxxxxxxxxxxxx Closes: https://syzkaller.appspot.com/bug?extid=30a35a2e9c5067cc43fa Signed-off-by: Abhishek Chauhan <quic_abchauha@xxxxxxxxxxx> Acked-by: Martin KaFai Lau <martin.lau@xxxxxxxxxx> --- Changes since v1 - Moved from net to net-next since Fixes tag is available only on net-next as mentioned by Martin - Added direct link to design discussion as mentioned by Willem. - Parameter in the sockopt_validate_clockid is of type __kernel_clockid_t so changed it from int to __kernel_clockid_t as mentioned by Willem. - Added Acked-by tag. net/core/sock.c | 16 ++++++++++++++++ 1 file changed, 16 insertions(+) diff --git a/net/core/sock.c b/net/core/sock.c index 8629f9aecf91..d497285f283a 100644 --- a/net/core/sock.c +++ b/net/core/sock.c @@ -1083,6 +1083,17 @@ bool sockopt_capable(int cap) } EXPORT_SYMBOL(sockopt_capable); +static int sockopt_validate_clockid(__kernel_clockid_t value) +{ + switch (value) { + case CLOCK_REALTIME: + case CLOCK_MONOTONIC: + case CLOCK_TAI: + return 0; + } + return -EINVAL; +} + /* * This is meant for all protocols to use and covers goings on * at the socket level. Everything here is generic. @@ -1497,6 +1508,11 @@ int sk_setsockopt(struct sock *sk, int level, int optname, ret = -EPERM; break; } + + ret = sockopt_validate_clockid(sk_txtime.clockid); + if (ret) + break; + sock_valbool_flag(sk, SOCK_TXTIME, true); sk->sk_clockid = sk_txtime.clockid; sk->sk_txtime_deadline_mode = -- 2.25.1
