Description of problem: This problem was originally tracked down by Brad Spengler.
When calling wireless ioctls, if a driver does not correctly validate/shrink iwp->length, the resulting copytouser can leak up to 64K of kernel heap contents.
It seems that this is triggerable[1] in 2.6.32 at least on ath5k, but I was not able to track down how. The twisty maze of ioctl handlers stumped me. :) Other drivers I checked did not appear to have any problems, but the potential remains. I'm not sure if this patch is the right approach; it was fixed differently[2] in grsecurity.
[1] http://forums.grsecurity.net/viewtopic.php?f=3&t=2290&start=0 [2] http://grsecurity.net/~spender/wireless-infoleak-fix2.patch
Discussion: http://lkml.org/lkml/2010/8/27/413
Description of problem: http://lkml.org/lkml/2010/9/11/168 The EQLGETMASTRCFG device ioctl allows unprivileged users to read 16 bytes of uninitialized stack memory, because the "mastername" member of the masterconfigt struct declared on the stack in eqlgmastercfg() is not altered or zeroed before being copied back to the user.
Acknowledgements:
Red Hat would like to thank Dan Rosenberg for reporting this issue.
Description of problem: http://lkml.org/lkml/2010/9/11/170 The CHELSIOGETQSETNUM device ioctl allows unprivileged users to read 4 bytes of uninitialized stack memory, because the "addr" member of the chreg struct declared on the stack in cxgbextensionioctl() is not altered or zeroed before being copied back to the user.
Acknowledgements:
Red Hat would like to thank Dan Rosenberg for reporting this issue.
Description of problem: There is a problem with the ioctl subsystem for drm, though it is most explicitly exposed by the intel GEM driver. Under driver-defined ioctls, drm does not sanitize the ioctl command, allowing the caller to specify how much memory should be kmalloc'd and copied back to the caller, regardless of what the driver ioctl actually does (it doesn't even need to succeed).
drivers/gpu/drm/drmdrv.c
long drmioctl(struct file filp, unsigned int cmd, unsigned long arg) ... unsigned int nr = DRMIOCTLNR(cmd); ... if ((nr >= DRMCOMMANDBASE) && (nr < DRMCOMMANDEND) && (nr < DRMCOMMANDBASE + dev->driver->numioctls)) ioctl = &dev->driver->ioctls[nr - DRMCOMMANDBASE]; ... if (cmd & (IOCIN | IOCOUT)) { if (IOCSIZE(cmd) <= sizeof(stackkdata)) { kdata = stackkdata; } else { kdata = kmalloc(IOCSIZE(cmd), GFPKERNEL); ... } } ... retcode = func(dev, kdata, filepriv); ... if (cmd & IOCOUT) { if (copytouser((void user )arg, kdata, IOCSIZE(cmd)) != 0) retcode = -EFAULT; }
"cmd" is caller-controlled, and can do whatever it likes for IOCSIZE(cmd), IOCIN and IOCOUT, resulting in leakage of previously freed kernel heap memory contents up to 16K in size.
Buffer overflow in the utilpathencode function in udev/lib/libudev-util.c in udev before 1.4.1 allows local users to cause a denial of service (service outage) via vectors that trigger a call with crafted arguments.