--- /dev/null
+From 05a7f4a8dff19999ca8a83a35ff4782689de7bfc Mon Sep 17 00:00:00 2001
+From: Leon Romanovsky <leonro@nvidia.com>
+Date: Thu, 29 Jul 2021 20:19:24 +0300
+Subject: devlink: Break parameter notification sequence to be before/after unload/load driver
+
+From: Leon Romanovsky <leonro@nvidia.com>
+
+commit 05a7f4a8dff19999ca8a83a35ff4782689de7bfc upstream.
+
+The change of namespaces during devlink reload calls to driver unload
+before it accesses devlink parameters. The commands below causes to
+use-after-free bug when trying to get flow steering mode.
+
+ * ip netns add n1
+ * devlink dev reload pci/0000:00:09.0 netns n1
+
+ ==================================================================
+ BUG: KASAN: use-after-free in mlx5_devlink_fs_mode_get+0x96/0xa0 [mlx5_core]
+ Read of size 4 at addr ffff888009d04308 by task devlink/275
+
+ CPU: 6 PID: 275 Comm: devlink Not tainted 5.12.0-rc2+ #2853
+ Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.13.0-0-gf21b5a4aeb02-prebuilt.qemu.org 04/01/2014
+ Call Trace:
+ dump_stack+0x93/0xc2
+ print_address_description.constprop.0+0x18/0x140
+ ? mlx5_devlink_fs_mode_get+0x96/0xa0 [mlx5_core]
+ ? mlx5_devlink_fs_mode_get+0x96/0xa0 [mlx5_core]
+ kasan_report.cold+0x7c/0xd8
+ ? mlx5_devlink_fs_mode_get+0x96/0xa0 [mlx5_core]
+ mlx5_devlink_fs_mode_get+0x96/0xa0 [mlx5_core]
+ devlink_nl_param_fill+0x1c8/0xe80
+ ? __free_pages_ok+0x37a/0x8a0
+ ? devlink_flash_update_timeout_notify+0xd0/0xd0
+ ? lock_acquire+0x1a9/0x6d0
+ ? fs_reclaim_acquire+0xb7/0x160
+ ? lock_is_held_type+0x98/0x110
+ ? 0xffffffff81000000
+ ? lock_release+0x1f9/0x6c0
+ ? fs_reclaim_release+0xa1/0xf0
+ ? lock_downgrade+0x6d0/0x6d0
+ ? lock_is_held_type+0x98/0x110
+ ? lock_is_held_type+0x98/0x110
+ ? memset+0x20/0x40
+ ? __build_skb_around+0x1f8/0x2b0
+ devlink_param_notify+0x6d/0x180
+ devlink_reload+0x1c3/0x520
+ ? devlink_remote_reload_actions_performed+0x30/0x30
+ ? mutex_trylock+0x24b/0x2d0
+ ? devlink_nl_cmd_reload+0x62b/0x1070
+ devlink_nl_cmd_reload+0x66d/0x1070
+ ? devlink_reload+0x520/0x520
+ ? devlink_get_from_attrs+0x1bc/0x260
+ ? devlink_nl_pre_doit+0x64/0x4d0
+ genl_family_rcv_msg_doit+0x1e9/0x2f0
+ ? mutex_lock_io_nested+0x1130/0x1130
+ ? genl_family_rcv_msg_attrs_parse.constprop.0+0x240/0x240
+ ? security_capable+0x51/0x90
+ genl_rcv_msg+0x27f/0x4a0
+ ? genl_get_cmd+0x3c0/0x3c0
+ ? lock_acquire+0x1a9/0x6d0
+ ? devlink_reload+0x520/0x520
+ ? lock_release+0x6c0/0x6c0
+ netlink_rcv_skb+0x11d/0x340
+ ? genl_get_cmd+0x3c0/0x3c0
+ ? netlink_ack+0x9f0/0x9f0
+ ? lock_release+0x1f9/0x6c0
+ genl_rcv+0x24/0x40
+ netlink_unicast+0x433/0x700
+ ? netlink_attachskb+0x730/0x730
+ ? _copy_from_iter_full+0x178/0x650
+ ? __alloc_skb+0x113/0x2b0
+ netlink_sendmsg+0x6f1/0xbd0
+ ? netlink_unicast+0x700/0x700
+ ? lock_is_held_type+0x98/0x110
+ ? netlink_unicast+0x700/0x700
+ sock_sendmsg+0xb0/0xe0
+ __sys_sendto+0x193/0x240
+ ? __x64_sys_getpeername+0xb0/0xb0
+ ? do_sys_openat2+0x10b/0x370
+ ? __up_read+0x1a1/0x7b0
+ ? do_user_addr_fault+0x219/0xdc0
+ ? __x64_sys_openat+0x120/0x1d0
+ ? __x64_sys_open+0x1a0/0x1a0
+ __x64_sys_sendto+0xdd/0x1b0
+ ? syscall_enter_from_user_mode+0x1d/0x50
+ do_syscall_64+0x2d/0x40
+ entry_SYSCALL_64_after_hwframe+0x44/0xae
+ RIP: 0033:0x7fc69d0af14a
+ Code: d8 64 89 02 48 c7 c0 ff ff ff ff eb b8 0f 1f 00 f3 0f 1e fa 41 89 ca 64 8b 04 25 18 00 00 00 85 c0 75 15 b8 2c 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 76 c3 0f 1f 44 00 00 55 48 83 ec 30 44 89 4c
+ RSP: 002b:00007ffc1d8292f8 EFLAGS: 00000246 ORIG_RAX: 000000000000002c
+ RAX: ffffffffffffffda RBX: 0000000000000005 RCX: 00007fc69d0af14a
+ RDX: 0000000000000038 RSI: 0000555f57c56440 RDI: 0000000000000003
+ RBP: 0000555f57c56410 R08: 00007fc69d17b200 R09: 000000000000000c
+ R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
+ R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
+
+ Allocated by task 146:
+ kasan_save_stack+0x1b/0x40
+ __kasan_kmalloc+0x99/0xc0
+ mlx5_init_fs+0xf0/0x1c50 [mlx5_core]
+ mlx5_load+0xd2/0x180 [mlx5_core]
+ mlx5_init_one+0x2f6/0x450 [mlx5_core]
+ probe_one+0x47d/0x6e0 [mlx5_core]
+ pci_device_probe+0x2a0/0x4a0
+ really_probe+0x20a/0xc90
+ driver_probe_device+0xd8/0x380
+ device_driver_attach+0x1df/0x250
+ __driver_attach+0xff/0x240
+ bus_for_each_dev+0x11e/0x1a0
+ bus_add_driver+0x309/0x570
+ driver_register+0x1ee/0x380
+ 0xffffffffa06b8062
+ do_one_initcall+0xd5/0x410
+ do_init_module+0x1c8/0x760
+ load_module+0x6d8b/0x9650
+ __do_sys_finit_module+0x118/0x1b0
+ do_syscall_64+0x2d/0x40
+ entry_SYSCALL_64_after_hwframe+0x44/0xae
+
+ Freed by task 275:
+ kasan_save_stack+0x1b/0x40
+ kasan_set_track+0x1c/0x30
+ kasan_set_free_info+0x20/0x30
+ __kasan_slab_free+0x102/0x140
+ slab_free_freelist_hook+0x74/0x1b0
+ kfree+0xd7/0x2a0
+ mlx5_unload+0x16/0xb0 [mlx5_core]
+ mlx5_unload_one+0xae/0x120 [mlx5_core]
+ mlx5_devlink_reload_down+0x1bc/0x380 [mlx5_core]
+ devlink_reload+0x141/0x520
+ devlink_nl_cmd_reload+0x66d/0x1070
+ genl_family_rcv_msg_doit+0x1e9/0x2f0
+ genl_rcv_msg+0x27f/0x4a0
+ netlink_rcv_skb+0x11d/0x340
+ genl_rcv+0x24/0x40
+ netlink_unicast+0x433/0x700
+ netlink_sendmsg+0x6f1/0xbd0
+ sock_sendmsg+0xb0/0xe0
+ __sys_sendto+0x193/0x240
+ __x64_sys_sendto+0xdd/0x1b0
+ do_syscall_64+0x2d/0x40
+ entry_SYSCALL_64_after_hwframe+0x44/0xae
+
+ The buggy address belongs to the object at ffff888009d04300
+ which belongs to the cache kmalloc-128 of size 128
+ The buggy address is located 8 bytes inside of
+ 128-byte region [ffff888009d04300, ffff888009d04380)
+ The buggy address belongs to the page:
+ page:0000000086a64ecc refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff888009d04000 pfn:0x9d04
+ head:0000000086a64ecc order:1 compound_mapcount:0
+ flags: 0x4000000000010200(slab|head)
+ raw: 4000000000010200 ffffea0000203980 0000000200000002 ffff8880050428c0
+ raw: ffff888009d04000 000000008020001d 00000001ffffffff 0000000000000000
+ page dumped because: kasan: bad access detected
+
+ Memory state around the buggy address:
+ ffff888009d04200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
+ ffff888009d04280: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
+ >ffff888009d04300: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
+ ^
+ ffff888009d04380: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
+ ffff888009d04400: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
+ ==================================================================
+
+The right solution to devlink reload is to notify about deletion of
+parameters, unload driver, change net namespaces, load driver and notify
+about addition of parameters.
+
+Fixes: 070c63f20f6c ("net: devlink: allow to change namespaces during reload")
+Reviewed-by: Parav Pandit <parav@nvidia.com>
+Signed-off-by: Leon Romanovsky <leonro@nvidia.com>
+Signed-off-by: Jakub Kicinski <kuba@kernel.org>
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+---
+ net/core/devlink.c | 32 ++++++++++++++++++++------------
+ 1 file changed, 20 insertions(+), 12 deletions(-)
+
+--- a/net/core/devlink.c
++++ b/net/core/devlink.c
+@@ -3801,10 +3801,12 @@ static void devlink_param_notify(struct
+ struct devlink_param_item *param_item,
+ enum devlink_command cmd);
+
+-static void devlink_reload_netns_change(struct devlink *devlink,
+- struct net *dest_net)
++static void devlink_ns_change_notify(struct devlink *devlink,
++ struct net *dest_net, struct net *curr_net,
++ bool new)
+ {
+ struct devlink_param_item *param_item;
++ enum devlink_command cmd;
+
+ /* Userspace needs to be notified about devlink objects
+ * removed from original and entering new network namespace.
+@@ -3812,17 +3814,18 @@ static void devlink_reload_netns_change(
+ * reload process so the notifications are generated separatelly.
+ */
+
+- list_for_each_entry(param_item, &devlink->param_list, list)
+- devlink_param_notify(devlink, 0, param_item,
+- DEVLINK_CMD_PARAM_DEL);
+- devlink_notify(devlink, DEVLINK_CMD_DEL);
++ if (!dest_net || net_eq(dest_net, curr_net))
++ return;
+
+- __devlink_net_set(devlink, dest_net);
++ if (new)
++ devlink_notify(devlink, DEVLINK_CMD_NEW);
+
+- devlink_notify(devlink, DEVLINK_CMD_NEW);
++ cmd = new ? DEVLINK_CMD_PARAM_NEW : DEVLINK_CMD_PARAM_DEL;
+ list_for_each_entry(param_item, &devlink->param_list, list)
+- devlink_param_notify(devlink, 0, param_item,
+- DEVLINK_CMD_PARAM_NEW);
++ devlink_param_notify(devlink, 0, param_item, cmd);
++
++ if (!new)
++ devlink_notify(devlink, DEVLINK_CMD_DEL);
+ }
+
+ static bool devlink_reload_supported(const struct devlink_ops *ops)
+@@ -3902,6 +3905,7 @@ static int devlink_reload(struct devlink
+ u32 *actions_performed, struct netlink_ext_ack *extack)
+ {
+ u32 remote_reload_stats[DEVLINK_RELOAD_STATS_ARRAY_SIZE];
++ struct net *curr_net;
+ int err;
+
+ if (!devlink->reload_enabled)
+@@ -3909,18 +3913,22 @@ static int devlink_reload(struct devlink
+
+ memcpy(remote_reload_stats, devlink->stats.remote_reload_stats,
+ sizeof(remote_reload_stats));
++
++ curr_net = devlink_net(devlink);
++ devlink_ns_change_notify(devlink, dest_net, curr_net, false);
+ err = devlink->ops->reload_down(devlink, !!dest_net, action, limit, extack);
+ if (err)
+ return err;
+
+- if (dest_net && !net_eq(dest_net, devlink_net(devlink)))
+- devlink_reload_netns_change(devlink, dest_net);
++ if (dest_net && !net_eq(dest_net, curr_net))
++ __devlink_net_set(devlink, dest_net);
+
+ err = devlink->ops->reload_up(devlink, action, limit, actions_performed, extack);
+ devlink_reload_failed_set(devlink, !!err);
+ if (err)
+ return err;
+
++ devlink_ns_change_notify(devlink, dest_net, curr_net, true);
+ WARN_ON(!(*actions_performed & BIT(action)));
+ /* Catch driver on updating the remote action within devlink reload */
+ WARN_ON(memcmp(remote_reload_stats, devlink->stats.remote_reload_stats,
projects / thirdparty / kernel / stable-queue.git / commitdiff
