diff options
| author | Alan Coopersmith <alan.coopersmith@oracle.com> | 2014-01-06 23:30:14 -0800 |
|---|---|---|
| committer | Mike Gabriel <mike.gabriel@das-netzwerkteam.de> | 2015-02-14 16:14:31 +0100 |
| commit | d4c76981f7fddb364166464c571ed8d3de3086cd (patch) | |
| tree | 4e3d6c0465164e02a944e791c09a34dc34c6c58c /nx-X11/programs/Xserver | |
| parent | c1225fe6451d7a5f3741ce0fff8f54e38e0a14da (diff) | |
| download | nx-libs-d4c76981f7fddb364166464c571ed8d3de3086cd.tar.gz nx-libs-d4c76981f7fddb364166464c571ed8d3de3086cd.tar.bz2 nx-libs-d4c76981f7fddb364166464c571ed8d3de3086cd.zip | |
dix: integer overflow in GetHosts() [CVE-2014-8092 2/4]
GetHosts() iterates over all the hosts it has in memory, and copies
them to a buffer. The buffer length is calculated by iterating over
all the hosts and adding up all of their combined length. There is a
potential integer overflow, if there are lots and lots of hosts (with
a combined length of > ~4 gig). This should be possible by repeatedly
calling ProcChangeHosts() on 64bit machines with enough memory.
This patch caps the list at 1mb, because multi-megabyte hostname
lists for X access control are insane.
v2: backport to nx-libs 3.6.x (Mike DePaulo)
Reported-by: Ilja Van Sprundel <ivansprundel@ioactive.com>
Signed-off-by: Alan Coopersmith <alan.coopersmith@oracle.com>
Reviewed-by: Peter Hutterer <peter.hutterer@who-t.net>
Conflicts:
os/access.c
Diffstat (limited to 'nx-X11/programs/Xserver')
| -rw-r--r-- | nx-X11/programs/Xserver/os/access.c | 6 |
1 files changed, 6 insertions, 0 deletions
diff --git a/nx-X11/programs/Xserver/os/access.c b/nx-X11/programs/Xserver/os/access.c index b6a70a703..0e9d13845 100644 --- a/nx-X11/programs/Xserver/os/access.c +++ b/nx-X11/programs/Xserver/os/access.c @@ -1719,6 +1719,10 @@ GetHosts ( { nHosts++; n += (((host->len + 3) >> 2) << 2) + sizeof(xHostEntry); + /* Could check for INT_MAX, but in reality having more than 1mb of + hostnames in the access list is ridiculous */ + if (n >= 1048576) + break; } if (n) { @@ -1730,6 +1734,8 @@ GetHosts ( for (host = validhosts; host; host = host->next) { len = host->len; + if ((ptr + sizeof(xHostEntry) + len) > (data + n)) + break; ((xHostEntry *)ptr)->family = host->family; ((xHostEntry *)ptr)->length = len; ptr += sizeof(xHostEntry); |