slirp: Convert mbufs to use g_malloc() and g_free()

The mbuf code currently doesn't check the result of doing a malloc()
or realloc() of its data (spotted by Coverity, CID 1238946).
Since the m_inc() API assumes that extending an mbuf must succeed,
just convert to g_malloc() and g_free().

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Samuel Thibault <samuel.thibault@ens-lyon.org>
This commit is contained in:
Peter Maydell 2017-02-04 23:08:34 +00:00 committed by Samuel Thibault
parent 4577b09a27
commit 70f2e64e4d

View file

@ -10,7 +10,7 @@
* FreeBSD. They are fixed size, determined by the MTU,
* so that one whole packet can fit. Mbuf's cannot be
* chained together. If there's more data than the mbuf
* could hold, an external malloced buffer is pointed to
* could hold, an external g_malloced buffer is pointed to
* by m_ext (and the data pointers) and M_EXT is set in
* the flags
*/
@ -41,26 +41,26 @@ void m_cleanup(Slirp *slirp)
while ((struct quehead *) m != &slirp->m_usedlist) {
next = m->m_next;
if (m->m_flags & M_EXT) {
free(m->m_ext);
g_free(m->m_ext);
}
free(m);
g_free(m);
m = next;
}
m = (struct mbuf *) slirp->m_freelist.qh_link;
while ((struct quehead *) m != &slirp->m_freelist) {
next = m->m_next;
free(m);
g_free(m);
m = next;
}
}
/*
* Get an mbuf from the free list, if there are none
* malloc one
* allocate one
*
* Because fragmentation can occur if we alloc new mbufs and
* free old mbufs, we mark all mbufs above mbuf_thresh as M_DOFREE,
* which tells m_free to actually free() it
* which tells m_free to actually g_free() it
*/
struct mbuf *
m_get(Slirp *slirp)
@ -71,8 +71,7 @@ m_get(Slirp *slirp)
DEBUG_CALL("m_get");
if (slirp->m_freelist.qh_link == &slirp->m_freelist) {
m = (struct mbuf *)malloc(SLIRP_MSIZE);
if (m == NULL) goto end_error;
m = g_malloc(SLIRP_MSIZE);
slirp->mbuf_alloced++;
if (slirp->mbuf_alloced > MBUF_THRESH)
flags = M_DOFREE;
@ -94,7 +93,6 @@ m_get(Slirp *slirp)
m->m_prevpkt = NULL;
m->resolution_requested = false;
m->expiration_date = (uint64_t)-1;
end_error:
DEBUG_ARG("m = %p", m);
return m;
}
@ -112,15 +110,15 @@ m_free(struct mbuf *m)
remque(m);
/* If it's M_EXT, free() it */
if (m->m_flags & M_EXT)
free(m->m_ext);
if (m->m_flags & M_EXT) {
g_free(m->m_ext);
}
/*
* Either free() it or put it on the free list
*/
if (m->m_flags & M_DOFREE) {
m->slirp->mbuf_alloced--;
free(m);
g_free(m);
} else if ((m->m_flags & M_FREELIST) == 0) {
insque(m,&m->slirp->m_freelist);
m->m_flags = M_FREELIST; /* Clobber other flags */
@ -130,7 +128,7 @@ m_free(struct mbuf *m)
/*
* Copy data from one mbuf to the end of
* the other.. if result is too big for one mbuf, malloc()
* the other.. if result is too big for one mbuf, allocate
* an M_EXT data segment
*/
void
@ -160,12 +158,12 @@ m_inc(struct mbuf *m, int size)
if (m->m_flags & M_EXT) {
datasize = m->m_data - m->m_ext;
m->m_ext = (char *)realloc(m->m_ext,size);
m->m_ext = g_realloc(m->m_ext, size);
m->m_data = m->m_ext + datasize;
} else {
char *dat;
datasize = m->m_data - m->m_dat;
dat = (char *)malloc(size);
dat = g_malloc(size);
memcpy(dat, m->m_dat, m->m_size);
m->m_ext = dat;