Gitweb: http://git.kernel.org/linus/06f1631a1671bce2d59d58cb1debdf23e1803ebf
Commit: 06f1631a1671bce2d59d58cb1debdf23e1803ebf
Parent: 4a30debfb778240a4b1767d4b0c5a5b25ab97160
Author: Oleg Nesterov <oleg@redhat.com>
AuthorDate: Wed Sep 23 15:57:01 2009 -0700
Committer: Linus Torvalds <torvalds@linux-foundation.org>
CommitDate: Thu Sep 24 07:21:01 2009 -0700
signals: send_sigio: use do_send_sig_info() to avoid check_kill_permission()
group_send_sig_info()->check_kill_permission() assumes that current is the
sender and uses current_cred().
This is not true in send_sigio_to_task() case. From the security pov the
sender is not current, but the task which did fcntl(F_SETOWN), that is why
we have sigio_perm() which uses the right creds to check.
Fortunately, send_sigio() always sends either SEND_SIG_PRIV or
SI_FROMKERNEL() signal, so check_kill_permission() does nothing. But
still it would be tidier to avoid this bogus security check and save a
couple of cycles.
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: stephane eranian <eranian@googlemail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Roland McGrath <roland@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
---
fs/fcntl.c | 4 ++--
1 files changed, 2 insertions(+), 2 deletions(-)
diff --git a/fs/fcntl.c b/fs/fcntl.c
index ae41308..50a9889 100644
--- a/fs/fcntl.c
+++ b/fs/fcntl.c
@@ -461,11 +461,11 @@ static void send_sigio_to_task(struct task_struct *p,
else
si.si_band = band_table[reason - POLL_IN];
si.si_fd = fd;
- if (!group_send_sig_info(signum, &si, p))
+ if (!do_send_sig_info(signum, &si, p, true))
break;
/* fall-through: fall back on the old plain SIGIO signal */
case 0:
- group_send_sig_info(SIGIO, SEND_SIG_PRIV, p);
+ do_send_sig_info(SIGIO, SEND_SIG_PRIV, p, true);
}
}
--
To unsubscribe from this list: send the line "unsubscribe git-commits-head" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
