[PATCH] Using possibly corrupted structure in atm/he.c
From: Felipe W Damasio
Date: Sat Sep 20 2003 - 23:24:01 EST
Hi Chas,
Patch against 2.6-test5.
If copy_from_user returns != 0, it means the the regs structure wasn't
filled correctly, and since its fields are used to determine which ioctl
the user is requesting the kernel could oops.
And as long as we're covering the subject, the patch also audits
copy_to_user on the same function to check a possible failure to copy
the result back to userspace.
These bugs were found by smatch.
Please consider applying.
Cheers,
Felipe
--
It's most certainly GNU/Linux, not Linux. Read more at
http://www.gnu.org/gnu/why-gnu-linux.html
--- linux-2.6.0-test5/drivers/atm/he.c Mon Sep 8 16:49:54 2003
+++ linux-2.6.0-test5-fwd/drivers/atm/he.c Sun Sep 21 01:13:39 2003
@@ -2860,8 +2860,10 @@
if (!capable(CAP_NET_ADMIN))
return -EPERM;
- copy_from_user(®, (struct he_ioctl_reg *) arg,
- sizeof(struct he_ioctl_reg));
+ if (copy_from_user(®, (struct he_ioctl_reg *) arg,
+ sizeof(struct he_ioctl_reg)))
+ return -EFAULT;
+
spin_lock_irqsave(&he_dev->global_lock, flags);
switch (reg.type) {
case HE_REGTYPE_PCI:
@@ -2885,8 +2887,9 @@
}
spin_unlock_irqrestore(&he_dev->global_lock, flags);
if (err == 0)
- copy_to_user((struct he_ioctl_reg *) arg, ®,
- sizeof(struct he_ioctl_reg));
+ if (copy_to_user((struct he_ioctl_reg *) arg, ®,
+ sizeof(struct he_ioctl_reg)))
+ return -EFAULT;
break;
default:
#ifdef CONFIG_ATM_HE_USE_SUNI