svn commit: r324045 - head/sys/kern
Mateusz Guzik
mjg at FreeBSD.org
Wed Sep 27 01:31:53 UTC 2017
Author: mjg
Date: Wed Sep 27 01:31:52 2017
New Revision: 324045
URL: https://svnweb.freebsd.org/changeset/base/324045
Log:
sysctl: remove target buffer read/write checks prior to calling the handler
Said checks were inherently racy anyway as jokers could unmap target areas
before the handler got around to accessing them.
This saves time by avoiding locking the address space.
MFC after: 1 week
Modified:
head/sys/kern/kern_sysctl.c
Modified: head/sys/kern/kern_sysctl.c
==============================================================================
--- head/sys/kern/kern_sysctl.c Wed Sep 27 01:27:43 2017 (r324044)
+++ head/sys/kern/kern_sysctl.c Wed Sep 27 01:31:52 2017 (r324045)
@@ -2061,16 +2061,9 @@ userland_sysctl(struct thread *td, int *name, u_int na
}
}
req.validlen = req.oldlen;
+ req.oldptr = old;
- if (old) {
- if (!useracc(old, req.oldlen, VM_PROT_WRITE))
- return (EFAULT);
- req.oldptr= old;
- }
-
if (new != NULL) {
- if (!useracc(new, newlen, VM_PROT_READ))
- return (EFAULT);
req.newlen = newlen;
req.newptr = new;
}
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