The patch below does not apply to the 5.4-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <stable@xxxxxxxxxxxxxxx>. To reproduce the conflict and resubmit, you may use the following commands: git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-5.4.y git checkout FETCH_HEAD git cherry-pick -x ee8b94c8510ce64afe0b87ef548d23e00915fb10 # <resolve conflicts, build, test, etc.> git commit -s git send-email --to '<stable@xxxxxxxxxxxxxxx>' --in-reply-to '2023072356-marlin-untrue-8b08@gregkh' --subject-prefix 'PATCH 5.4.y' HEAD^.. Possible dependencies: ee8b94c8510c ("can: raw: fix receiver memory leak") 1160dfa178eb ("net: Remove redundant if statements") 54f93336d000 ("can: raw: raw_setsockopt(): fix raw_rcv panic for sock UAF") e032f7c9c7ce ("net/packet: annotate accesses to po->ifindex") c7d2ef5dd4b0 ("net/packet: annotate accesses to po->bind") 8d0caedb7596 ("can: bcm/raw/isotp: use per module netdevice notifier") d329ea5bd884 ("icmp: add response to RFC 8335 PROBE messages") eeff3000f240 ("netfilter: flowtable: add offload support for xmit path types") 3d453f53c786 ("net/smc: Add diagnostic information to smc ib-device") ddc992866f13 ("net/smc: Add link counters for IB device ports") e057dd3fc20f ("can: add ISO 15765-2:2016 transport protocol") 5855357cd40e ("drop_monitor: Prepare probe functions for devlink tracepoint") 6a54dde843f7 ("can: raw: fix indention") 504776be46cb ("nl80211: Simplify error handling path in 'nl80211_trigger_scan()'") 63673597cca9 ("net/smc: protect smc ib device initialization") 92f3cb0e11dd ("net/smc: fix sleep bug in smc_pnet_find_roce_resource()") 242b23319809 ("Merge tag 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rdma/rdma") thanks, greg k-h ------------------ original commit in Linus's tree ------------------ >From ee8b94c8510ce64afe0b87ef548d23e00915fb10 Mon Sep 17 00:00:00 2001 From: Ziyang Xuan <william.xuanziyang@xxxxxxxxxx> Date: Tue, 11 Jul 2023 09:17:37 +0800 Subject: [PATCH] can: raw: fix receiver memory leak Got kmemleak errors with the following ltp can_filter testcase: for ((i=1; i<=100; i++)) do ./can_filter & sleep 0.1 done ============================================================== [<00000000db4a4943>] can_rx_register+0x147/0x360 [can] [<00000000a289549d>] raw_setsockopt+0x5ef/0x853 [can_raw] [<000000006d3d9ebd>] __sys_setsockopt+0x173/0x2c0 [<00000000407dbfec>] __x64_sys_setsockopt+0x61/0x70 [<00000000fd468496>] do_syscall_64+0x33/0x40 [<00000000b7e47d51>] entry_SYSCALL_64_after_hwframe+0x61/0xc6 It's a bug in the concurrent scenario of unregister_netdevice_many() and raw_release() as following: cpu0 cpu1 unregister_netdevice_many(can_dev) unlist_netdevice(can_dev) // dev_get_by_index() return NULL after this net_set_todo(can_dev) raw_release(can_socket) dev = dev_get_by_index(, ro->ifindex); // dev == NULL if (dev) { // receivers in dev_rcv_lists not free because dev is NULL raw_disable_allfilters(, dev, ); dev_put(dev); } ... ro->bound = 0; ... call_netdevice_notifiers(NETDEV_UNREGISTER, ) raw_notify(, NETDEV_UNREGISTER, ) if (ro->bound) // invalid because ro->bound has been set 0 raw_disable_allfilters(, dev, ); // receivers in dev_rcv_lists will never be freed Add a net_device pointer member in struct raw_sock to record bound can_dev, and use rtnl_lock to serialize raw_socket members between raw_bind(), raw_release(), raw_setsockopt() and raw_notify(). Use ro->dev to decide whether to free receivers in dev_rcv_lists. Fixes: 8d0caedb7596 ("can: bcm/raw/isotp: use per module netdevice notifier") Reviewed-by: Oliver Hartkopp <socketcan@xxxxxxxxxxxx> Acked-by: Oliver Hartkopp <socketcan@xxxxxxxxxxxx> Signed-off-by: Ziyang Xuan <william.xuanziyang@xxxxxxxxxx> Link: https://lore.kernel.org/all/20230711011737.1969582-1-william.xuanziyang@xxxxxxxxxx Cc: stable@xxxxxxxxxxxxxxx Signed-off-by: Marc Kleine-Budde <mkl@xxxxxxxxxxxxxx> diff --git a/net/can/raw.c b/net/can/raw.c index 15c79b079184..2302e4882967 100644 --- a/net/can/raw.c +++ b/net/can/raw.c @@ -84,6 +84,7 @@ struct raw_sock { struct sock sk; int bound; int ifindex; + struct net_device *dev; struct list_head notifier; int loopback; int recv_own_msgs; @@ -277,7 +278,7 @@ static void raw_notify(struct raw_sock *ro, unsigned long msg, if (!net_eq(dev_net(dev), sock_net(sk))) return; - if (ro->ifindex != dev->ifindex) + if (ro->dev != dev) return; switch (msg) { @@ -292,6 +293,7 @@ static void raw_notify(struct raw_sock *ro, unsigned long msg, ro->ifindex = 0; ro->bound = 0; + ro->dev = NULL; ro->count = 0; release_sock(sk); @@ -337,6 +339,7 @@ static int raw_init(struct sock *sk) ro->bound = 0; ro->ifindex = 0; + ro->dev = NULL; /* set default filter to single entry dfilter */ ro->dfilter.can_id = 0; @@ -385,19 +388,13 @@ static int raw_release(struct socket *sock) lock_sock(sk); + rtnl_lock(); /* remove current filters & unregister */ if (ro->bound) { - if (ro->ifindex) { - struct net_device *dev; - - dev = dev_get_by_index(sock_net(sk), ro->ifindex); - if (dev) { - raw_disable_allfilters(dev_net(dev), dev, sk); - dev_put(dev); - } - } else { + if (ro->dev) + raw_disable_allfilters(dev_net(ro->dev), ro->dev, sk); + else raw_disable_allfilters(sock_net(sk), NULL, sk); - } } if (ro->count > 1) @@ -405,8 +402,10 @@ static int raw_release(struct socket *sock) ro->ifindex = 0; ro->bound = 0; + ro->dev = NULL; ro->count = 0; free_percpu(ro->uniq); + rtnl_unlock(); sock_orphan(sk); sock->sk = NULL; @@ -422,6 +421,7 @@ static int raw_bind(struct socket *sock, struct sockaddr *uaddr, int len) struct sockaddr_can *addr = (struct sockaddr_can *)uaddr; struct sock *sk = sock->sk; struct raw_sock *ro = raw_sk(sk); + struct net_device *dev = NULL; int ifindex; int err = 0; int notify_enetdown = 0; @@ -431,14 +431,13 @@ static int raw_bind(struct socket *sock, struct sockaddr *uaddr, int len) if (addr->can_family != AF_CAN) return -EINVAL; + rtnl_lock(); lock_sock(sk); if (ro->bound && addr->can_ifindex == ro->ifindex) goto out; if (addr->can_ifindex) { - struct net_device *dev; - dev = dev_get_by_index(sock_net(sk), addr->can_ifindex); if (!dev) { err = -ENODEV; @@ -467,26 +466,20 @@ static int raw_bind(struct socket *sock, struct sockaddr *uaddr, int len) if (!err) { if (ro->bound) { /* unregister old filters */ - if (ro->ifindex) { - struct net_device *dev; - - dev = dev_get_by_index(sock_net(sk), - ro->ifindex); - if (dev) { - raw_disable_allfilters(dev_net(dev), - dev, sk); - dev_put(dev); - } - } else { + if (ro->dev) + raw_disable_allfilters(dev_net(ro->dev), + ro->dev, sk); + else raw_disable_allfilters(sock_net(sk), NULL, sk); - } } ro->ifindex = ifindex; ro->bound = 1; + ro->dev = dev; } out: release_sock(sk); + rtnl_unlock(); if (notify_enetdown) { sk->sk_err = ENETDOWN; @@ -553,9 +546,9 @@ static int raw_setsockopt(struct socket *sock, int level, int optname, rtnl_lock(); lock_sock(sk); - if (ro->bound && ro->ifindex) { - dev = dev_get_by_index(sock_net(sk), ro->ifindex); - if (!dev) { + dev = ro->dev; + if (ro->bound && dev) { + if (dev->reg_state != NETREG_REGISTERED) { if (count > 1) kfree(filter); err = -ENODEV; @@ -596,7 +589,6 @@ static int raw_setsockopt(struct socket *sock, int level, int optname, ro->count = count; out_fil: - dev_put(dev); release_sock(sk); rtnl_unlock(); @@ -614,9 +606,9 @@ static int raw_setsockopt(struct socket *sock, int level, int optname, rtnl_lock(); lock_sock(sk); - if (ro->bound && ro->ifindex) { - dev = dev_get_by_index(sock_net(sk), ro->ifindex); - if (!dev) { + dev = ro->dev; + if (ro->bound && dev) { + if (dev->reg_state != NETREG_REGISTERED) { err = -ENODEV; goto out_err; } @@ -640,7 +632,6 @@ static int raw_setsockopt(struct socket *sock, int level, int optname, ro->err_mask = err_mask; out_err: - dev_put(dev); release_sock(sk); rtnl_unlock();
