diff options
| author | Hannes Frederic Sowa <hannes@stressinduktion.org> | 2016-02-03 02:11:03 +0100 |
|---|---|---|
| committer | Sasha Levin <sasha.levin@oracle.com> | 2016-03-04 10:25:48 -0500 |
| commit | 797c009c98dbb21127a2549d1106ed19d18661cf (patch) | |
| tree | 3b3b0e2bd49506b51d5580c106cc68a1ff7c93af /include | |
| parent | 6c92a8f0502d3e9a9036473408f7f67b58f22ea9 (diff) | |
unix: correctly track in-flight fds in sending process user_struct
[ Upstream commit 415e3d3e90ce9e18727e8843ae343eda5a58fad6 ]
The commit referenced in the Fixes tag incorrectly accounted the number
of in-flight fds over a unix domain socket to the original opener
of the file-descriptor. This allows another process to arbitrary
deplete the original file-openers resource limit for the maximum of
open files. Instead the sending processes and its struct cred should
be credited.
To do so, we add a reference counted struct user_struct pointer to the
scm_fp_list and use it to account for the number of inflight unix fds.
Fixes: 712f4aad406bb1 ("unix: properly account for FDs passed over unix sockets")
Reported-by: David Herrmann <dh.herrmann@gmail.com>
Cc: David Herrmann <dh.herrmann@gmail.com>
Cc: Willy Tarreau <w@1wt.eu>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
Diffstat (limited to 'include')
| -rw-r--r-- | include/net/af_unix.h | 4 | ||||
| -rw-r--r-- | include/net/scm.h | 1 |
2 files changed, 3 insertions, 2 deletions
diff --git a/include/net/af_unix.h b/include/net/af_unix.h index e830c3dff61a..7bb69c9c3c43 100644 --- a/include/net/af_unix.h +++ b/include/net/af_unix.h @@ -6,8 +6,8 @@ #include <linux/mutex.h> #include <net/sock.h> -void unix_inflight(struct file *fp); -void unix_notinflight(struct file *fp); +void unix_inflight(struct user_struct *user, struct file *fp); +void unix_notinflight(struct user_struct *user, struct file *fp); void unix_gc(void); void wait_for_unix_gc(void); struct sock *unix_get_socket(struct file *filp); diff --git a/include/net/scm.h b/include/net/scm.h index 262532d111f5..59fa93c01d2a 100644 --- a/include/net/scm.h +++ b/include/net/scm.h @@ -21,6 +21,7 @@ struct scm_creds { struct scm_fp_list { short count; short max; + struct user_struct *user; struct file *fp[SCM_MAX_FD]; }; |