diff options
author | Alexander Mikhalitsyn <aleksandr.mikhalitsyn@canonical.com> | 2023-03-13 14:32:11 +0300 |
---|---|---|
committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2023-05-11 17:03:18 +0300 |
commit | af5265c64d8a5376a29cb2cda08ec47a77676365 (patch) | |
tree | 9ee896b016fff914794e8477ed61f7267a48f187 /include | |
parent | 1f1fba8b3a75ca528ecad31692433ffdec577a26 (diff) | |
download | linux-af5265c64d8a5376a29cb2cda08ec47a77676365.tar.xz |
scm: fix MSG_CTRUNC setting condition for SO_PASSSEC
[ Upstream commit a02d83f9947d8f71904eda4de046630c3eb6802c ]
Currently, kernel would set MSG_CTRUNC flag if msg_control buffer
wasn't provided and SO_PASSCRED was set or if there was pending SCM_RIGHTS.
For some reason we have no corresponding check for SO_PASSSEC.
In the recvmsg(2) doc we have:
MSG_CTRUNC
indicates that some control data was discarded due to lack
of space in the buffer for ancillary data.
So, we need to set MSG_CTRUNC flag for all types of SCM.
This change can break applications those don't check MSG_CTRUNC flag.
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Eric Dumazet <edumazet@google.com>
Cc: Jakub Kicinski <kuba@kernel.org>
Cc: Paolo Abeni <pabeni@redhat.com>
Cc: Leon Romanovsky <leon@kernel.org>
Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Signed-off-by: Alexander Mikhalitsyn <aleksandr.mikhalitsyn@canonical.com>
v2:
- commit message was rewritten according to Eric's suggestion
Acked-by: Paul Moore <paul@paul-moore.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Diffstat (limited to 'include')
-rw-r--r-- | include/net/scm.h | 13 |
1 files changed, 12 insertions, 1 deletions
diff --git a/include/net/scm.h b/include/net/scm.h index 1ce365f4c256..585adc1346bd 100644 --- a/include/net/scm.h +++ b/include/net/scm.h @@ -105,16 +105,27 @@ static inline void scm_passec(struct socket *sock, struct msghdr *msg, struct sc } } } + +static inline bool scm_has_secdata(struct socket *sock) +{ + return test_bit(SOCK_PASSSEC, &sock->flags); +} #else static inline void scm_passec(struct socket *sock, struct msghdr *msg, struct scm_cookie *scm) { } + +static inline bool scm_has_secdata(struct socket *sock) +{ + return false; +} #endif /* CONFIG_SECURITY_NETWORK */ static __inline__ void scm_recv(struct socket *sock, struct msghdr *msg, struct scm_cookie *scm, int flags) { if (!msg->msg_control) { - if (test_bit(SOCK_PASSCRED, &sock->flags) || scm->fp) + if (test_bit(SOCK_PASSCRED, &sock->flags) || scm->fp || + scm_has_secdata(sock)) msg->msg_flags |= MSG_CTRUNC; scm_destroy(scm); return; |