diff options
| author | Eric Dumazet <edumazet@google.com> | 2022-07-29 12:12:32 +0300 |
|---|---|---|
| committer | Jakub Kicinski <kuba@kernel.org> | 2022-08-01 21:59:23 +0300 |
| commit | 931027820e4dafabc78aff82af59f8c1c4bd3128 (patch) | |
| tree | 2ec2f883b9d11050ef6f01a59b0747b761f565c6 /net | |
| parent | 9936e07eaf5b764ff36c5677644bb5d556fb7e45 (diff) | |
| download | linux-931027820e4dafabc78aff82af59f8c1c4bd3128.tar.xz | |
net: rose: fix netdev reference changes
Bernard reported that trying to unload rose module would lead
to infamous messages:
unregistered_netdevice: waiting for rose0 to become free. Usage count = xx
This patch solves the issue, by making sure each socket referring to
a netdevice holds a reference count on it, and properly releases it
in rose_release().
rose_dev_first() is also fixed to take a device reference
before leaving the rcu_read_locked section.
Following patch will add ref_tracker annotations to ease
future bug hunting.
Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Reported-by: Bernard Pidoux <f6bvp@free.fr>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Tested-by: Bernard Pidoux <f6bvp@free.fr>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Diffstat (limited to 'net')
| -rw-r--r-- | net/rose/af_rose.c | 11 | ||||
| -rw-r--r-- | net/rose/rose_route.c | 2 |
2 files changed, 11 insertions, 2 deletions
diff --git a/net/rose/af_rose.c b/net/rose/af_rose.c index bf2d986a6bc3..a8e3ec800a9c 100644 --- a/net/rose/af_rose.c +++ b/net/rose/af_rose.c @@ -192,6 +192,7 @@ static void rose_kill_by_device(struct net_device *dev) rose_disconnect(s, ENETUNREACH, ROSE_OUT_OF_ORDER, 0); if (rose->neighbour) rose->neighbour->use--; + dev_put(rose->device); rose->device = NULL; } } @@ -592,6 +593,8 @@ static struct sock *rose_make_new(struct sock *osk) rose->idle = orose->idle; rose->defer = orose->defer; rose->device = orose->device; + if (rose->device) + dev_hold(rose->device); rose->qbitincl = orose->qbitincl; return sk; @@ -645,6 +648,7 @@ static int rose_release(struct socket *sock) break; } + dev_put(rose->device); sock->sk = NULL; release_sock(sk); sock_put(sk); @@ -721,7 +725,6 @@ static int rose_connect(struct socket *sock, struct sockaddr *uaddr, int addr_le struct rose_sock *rose = rose_sk(sk); struct sockaddr_rose *addr = (struct sockaddr_rose *)uaddr; unsigned char cause, diagnostic; - struct net_device *dev; ax25_uid_assoc *user; int n, err = 0; @@ -778,9 +781,12 @@ static int rose_connect(struct socket *sock, struct sockaddr *uaddr, int addr_le } if (sock_flag(sk, SOCK_ZAPPED)) { /* Must bind first - autobinding in this may or may not work */ + struct net_device *dev; + sock_reset_flag(sk, SOCK_ZAPPED); - if ((dev = rose_dev_first()) == NULL) { + dev = rose_dev_first(); + if (!dev) { err = -ENETUNREACH; goto out_release; } @@ -788,6 +794,7 @@ static int rose_connect(struct socket *sock, struct sockaddr *uaddr, int addr_le user = ax25_findbyuid(current_euid()); if (!user) { err = -EINVAL; + dev_put(dev); goto out_release; } diff --git a/net/rose/rose_route.c b/net/rose/rose_route.c index eb0b8197ac82..fee772b4637c 100644 --- a/net/rose/rose_route.c +++ b/net/rose/rose_route.c @@ -615,6 +615,8 @@ struct net_device *rose_dev_first(void) if (first == NULL || strncmp(dev->name, first->name, 3) < 0) first = dev; } + if (first) + dev_hold(first); rcu_read_unlock(); return first; |