[PATCH 10/14] aoe: increase net_device reference count while using it

From: Ed Cashin
Date: Thu Aug 23 2012 - 14:46:06 EST


This change eliminates the danger that the user could rmmod the driver
for a network interface that is being used for AoE by the aoe driver.

Signed-off-by: Ed Cashin <ecashin@xxxxxxxxxx>
---
drivers/block/aoe/aoecmd.c | 4 ++++
drivers/block/aoe/aoedev.c | 7 +++++++
2 files changed, 11 insertions(+), 0 deletions(-)

diff --git a/drivers/block/aoe/aoecmd.c b/drivers/block/aoe/aoecmd.c
index fec28738..c985b50 100644
--- a/drivers/block/aoe/aoecmd.c
+++ b/drivers/block/aoe/aoecmd.c
@@ -493,12 +493,15 @@ static void
ejectif(struct aoetgt *t, struct aoeif *ifp)
{
struct aoeif *e;
+ struct net_device *nd;
ulong n;

+ nd = ifp->nd;
e = t->ifs + NAOEIFS - 1;
n = (e - ifp) * sizeof *ifp;
memmove(ifp, ifp+1, n);
e->nd = NULL;
+ dev_put(nd);
}

static int
@@ -1325,6 +1328,7 @@ setifbcnt(struct aoetgt *t, struct net_device *nd, int bcnt)
pr_err("aoe: device setifbcnt failure; too many interfaces.\n");
return;
}
+ dev_hold(nd);
p->nd = nd;
p->bcnt = bcnt;
}
diff --git a/drivers/block/aoe/aoedev.c b/drivers/block/aoe/aoedev.c
index 3968fe6..6be7b38 100644
--- a/drivers/block/aoe/aoedev.c
+++ b/drivers/block/aoe/aoedev.c
@@ -295,6 +295,13 @@ freetgt(struct aoedev *d, struct aoetgt *t)
{
struct frame *f;
struct list_head *pos, *nx, *head;
+ struct aoeif *ifp;
+
+ for (ifp = t->ifs; ifp < &t->ifs[NAOEIFS]; ++ifp) {
+ if (!ifp->nd)
+ break;
+ dev_put(ifp->nd);
+ }

head = &t->ffree;
list_for_each_safe(pos, nx, head) {
--
1.7.2.5

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/