diff options
| author | Eric Dumazet <edumazet@google.com> | 2022-07-29 12:12:32 +0300 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2022-08-21 16:15:51 +0300 |
| commit | 9a070a4417660f0a2d01ee85a9914b342b0a7af8 (patch) | |
| tree | 5d932f50021741bfc0d85abdaeb211e09813b4fa /net | |
| parent | 397e52dec16839b1296a350d8a34f898f284e061 (diff) | |
| download | linux-9a070a4417660f0a2d01ee85a9914b342b0a7af8.tar.xz | |
net: rose: fix netdev reference changes
[ Upstream commit 931027820e4dafabc78aff82af59f8c1c4bd3128 ]
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>
Signed-off-by: Sasha Levin <sashal@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 cf7d974e0f61..29a208ed8fb8 100644 --- a/net/rose/af_rose.c +++ b/net/rose/af_rose.c @@ -191,6 +191,7 @@ 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; } } @@ -591,6 +592,8 @@ 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; @@ -644,6 +647,7 @@ static int rose_release(struct socket *sock) break; } + dev_put(rose->device); sock->sk = NULL; release_sock(sk); sock_put(sk); @@ -720,7 +724,6 @@ 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; @@ -777,9 +780,12 @@ 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; } @@ -787,6 +793,7 @@ 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 95b198f84a3a..981bdefd478b 100644 --- a/net/rose/rose_route.c +++ b/net/rose/rose_route.c @@ -613,6 +613,8 @@ 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; |