Aren/NetBSD
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

m_pulldown: fix mbuf leaks and chain truncation

Browse Source 
in the case that m_dup() returns a chain of mbufs.
eg. when you attempt to m_pulldown() the middle of
a large M_EXT mbuf.
This commit is contained in:
yamt 2004-07-21 12:09:43 +00:00
parent 7af0699fdd
commit 1e19d56b66
1 changed files with 9 additions and 4 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

13
sys/kern/uipc_mbuf2.c
View File

@ -1,4 +1,4 @@
/* $NetBSD: uipc_mbuf2.c,v 1.16 2003/11/13 01:48:12 jonathan Exp $ */
/* $NetBSD: uipc_mbuf2.c,v 1.17 2004/07/21 12:09:43 yamt Exp $ */
/* $KAME: uipc_mbuf2.c,v 1.29 2001/02/14 13:42:10 itojun Exp $ */
/*
@ -62,7 +62,7 @@
*/
#include <sys/cdefs.h>
__KERNEL_RCSID(0, "$NetBSD: uipc_mbuf2.c,v 1.16 2003/11/13 01:48:12 jonathan Exp $");
__KERNEL_RCSID(0, "$NetBSD: uipc_mbuf2.c,v 1.17 2004/07/21 12:09:43 yamt Exp $");
#include <sys/param.h>
#include <sys/systm.h>
@ -128,15 +128,20 @@ m_pulldown(struct mbuf *m, int off, int len, int *offp)
* chop the current mbuf into two pieces, set off to 0.
*/
if (len <= n->m_len - off) {
struct mbuf *mlast;
o = m_dup(n, off, n->m_len - off, M_DONTWAIT);
if (o == NULL) {
m_freem(m);
return NULL; /* ENOBUFS */
}
KASSERT(o->m_len >= len);
for (mlast = o; mlast->m_next != NULL; mlast = mlast->m_next)
;
n->m_len = off;
o->m_next = n->m_next;
mlast->m_next = n->m_next;
n->m_next = o;
n = n->m_next;
n = o;
off = 0;
goto ok;
}