user/sven/linux.git/drivers/net/netdevsim/dev.c, branch v5.5.8

netdevsim: fix panic in nsim_dev_take_snapshot_write()

2020-02-14T21:53:00Z

commit 8526ad9646b17c59b6d430d8baa8f152a14fe177 upstream. nsim_dev_take_snapshot_write() uses nsim_dev and nsim_dev->dummy_region. So, during this function, these data shouldn't be removed. But there is no protecting stuff in this function. There are two similar cases. 1. reload case reload could be called during nsim_dev_take_snapshot_write(). When reload is being executed, nsim_dev_reload_down() is called and it calls nsim_dev_reload_destroy(). nsim_dev_reload_destroy() calls devlink_region_destroy() to destroy nsim_dev->dummy_region. So, during nsim_dev_take_snapshot_write(), nsim_dev->dummy_region() would be removed. At this point, snapshot_write() would access freed pointer. In order to fix this case, take_snapshot file will be removed before devlink_region_destroy(). The take_snapshot file will be re-created by ->reload_up(). 2. del_device_store case del_device_store() also could call nsim_dev_reload_destroy() during nsim_dev_take_snapshot_write(). If so, panic would occur. This problem is actually the same problem with the first case. So, this problem will be fixed by the first case's solution. Test commands: modprobe netdevsim while : do echo 1 > /sys/bus/netdevsim/new_device & echo 1 > /sys/bus/netdevsim/del_device & devlink dev reload netdevsim/netdevsim1 & echo 1 > /sys/kernel/debug/netdevsim/netdevsim1/take_snapshot & done Splat looks like: [ 45.564513][ T975] general protection fault, probably for non-canonical address 0xdffffc000000003a: 0000 [#1] SMP DEI [ 45.566131][ T975] KASAN: null-ptr-deref in range [0x00000000000001d0-0x00000000000001d7] [ 45.566135][ T975] CPU: 1 PID: 975 Comm: bash Not tainted 5.5.0+ #322 [ 45.569020][ T975] Hardware name: innotek GmbH VirtualBox/VirtualBox, BIOS VirtualBox 12/01/2006 [ 45.569026][ T975] RIP: 0010:__mutex_lock+0x10a/0x14b0 [ 45.570518][ T975] Code: 08 84 d2 0f 85 7f 12 00 00 44 8b 0d 10 23 65 02 45 85 c9 75 29 49 8d 7f 68 48 b8 00 00 00 0f [ 45.570522][ T975] RSP: 0018:ffff888046ccfbf0 EFLAGS: 00010206 [ 45.572305][ T975] RAX: dffffc0000000000 RBX: 0000000000000000 RCX: 0000000000000000 [ 45.572308][ T975] RDX: 000000000000003a RSI: ffffffffac926440 RDI: 00000000000001d0 [ 45.576843][ T975] RBP: ffff888046ccfd70 R08: ffffffffab610645 R09: 0000000000000000 [ 45.576847][ T975] R10: ffff888046ccfd90 R11: ffffed100d6360ad R12: 0000000000000000 [ 45.578471][ T975] R13: dffffc0000000000 R14: ffffffffae1976c0 R15: 0000000000000168 [ 45.578475][ T975] FS: 00007f614d6e7740(0000) GS:ffff88806c400000(0000) knlGS:0000000000000000 [ 45.581492][ T975] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 45.582942][ T975] CR2: 00005618677d1cf0 CR3: 000000005fb9c002 CR4: 00000000000606e0 [ 45.584543][ T975] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 45.586633][ T975] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 45.589889][ T975] Call Trace: [ 45.591445][ T975] ? devlink_region_snapshot_create+0x55/0x4a0 [ 45.601250][ T975] ? mutex_lock_io_nested+0x1380/0x1380 [ 45.602817][ T975] ? mutex_lock_io_nested+0x1380/0x1380 [ 45.603875][ T975] ? mark_held_locks+0xa5/0xe0 [ 45.604769][ T975] ? _raw_spin_unlock_irqrestore+0x2d/0x50 [ 45.606147][ T975] ? __mutex_unlock_slowpath+0xd0/0x670 [ 45.607723][ T975] ? crng_backtrack_protect+0x80/0x80 [ 45.613530][ T975] ? wait_for_completion+0x390/0x390 [ 45.615152][ T975] ? devlink_region_snapshot_create+0x55/0x4a0 [ 45.616834][ T975] devlink_region_snapshot_create+0x55/0x4a0 [ ... ] Fixes: 4418f862d675 ("netdevsim: implement support for devlink region and snapshots") Signed-off-by: Taehee Yoo Signed-off-by: Jakub Kicinski Signed-off-by: Greg Kroah-Hartman

netdevsim: fix stack-out-of-bounds in nsim_dev_debugfs_init()

2020-02-11T12:36:38Z

[ Upstream commit 6fb8852b1298200da39bd85788bc5755d1d56f32 ] When netdevsim dev is being created, a debugfs directory is created. The variable "dev_ddir_name" is 16bytes device name pointer and device name is "netdevsim". The maximum dev id length is 10. So, 16bytes for device name isn't enough. Test commands: modprobe netdevsim echo "1000000000 0" > /sys/bus/netdevsim/new_device Splat looks like: [ 249.622710][ T900] BUG: KASAN: stack-out-of-bounds in number+0x824/0x880 [ 249.623658][ T900] Write of size 1 at addr ffff88804c527988 by task bash/900 [ 249.624521][ T900] [ 249.624830][ T900] CPU: 1 PID: 900 Comm: bash Not tainted 5.5.0+ #322 [ 249.625691][ T900] Hardware name: innotek GmbH VirtualBox/VirtualBox, BIOS VirtualBox 12/01/2006 [ 249.626712][ T900] Call Trace: [ 249.627103][ T900] dump_stack+0x96/0xdb [ 249.627639][ T900] ? number+0x824/0x880 [ 249.628173][ T900] print_address_description.constprop.5+0x1be/0x360 [ 249.629022][ T900] ? number+0x824/0x880 [ 249.629569][ T900] ? number+0x824/0x880 [ 249.630105][ T900] __kasan_report+0x12a/0x170 [ 249.630717][ T900] ? number+0x824/0x880 [ 249.631201][ T900] kasan_report+0xe/0x20 [ 249.631723][ T900] number+0x824/0x880 [ 249.632235][ T900] ? put_dec+0xa0/0xa0 [ 249.632716][ T900] ? rcu_read_lock_sched_held+0x90/0xc0 [ 249.633392][ T900] vsnprintf+0x63c/0x10b0 [ 249.633983][ T900] ? pointer+0x5b0/0x5b0 [ 249.634543][ T900] ? mark_lock+0x11d/0xc40 [ 249.635200][ T900] sprintf+0x9b/0xd0 [ 249.635750][ T900] ? scnprintf+0xe0/0xe0 [ 249.636370][ T900] nsim_dev_probe+0x63c/0xbf0 [netdevsim] [ ... ] Reviewed-by: Jakub Kicinski Fixes: ab1d0cc004d7 ("netdevsim: change debugfs tree topology") Signed-off-by: Taehee Yoo Signed-off-by: Jakub Kicinski Signed-off-by: Greg Kroah-Hartman

devlink: correct misspelling of snapshot

2020-01-11T22:30:24Z

The function to obtain a unique snapshot id was mistakenly typo'd as devlink_region_shapshot_id_get. Fix this typo by renaming the function and all of its users. Signed-off-by: Jacob Keller Acked-by: Jiri Pirko Signed-off-by: David S. Miller

devlink: disallow reload operation during device cleanup

2019-11-08T22:11:47Z

There is a race between driver code that does setup/cleanup of device and devlink reload operation that in some drivers works with the same code. Use after free could we easily obtained by running: while true; do echo 10 > /sys/bus/netdevsim/new_device devlink dev reload netdevsim/netdevsim10 & echo 10 > /sys/bus/netdevsim/del_device done Fix this by enabling reload only after setup of device is complete and disabling it at the beginning of the cleanup process. Reported-by: Ido Schimmel Fixes: 2d8dc5bbf4e7 ("devlink: Add support for reload") Signed-off-by: Jiri Pirko Acked-by: Jakub Kicinski Signed-off-by: David S. Miller

netdevsim: drop code duplicated by a merge

2019-11-06T17:59:57Z

Looks like the port adding loop makes a re-appearance on net-next after net was merged back into it (even though it doesn't feature in the merge diff). The ports are already added in nsim_dev_create() so when we try to add them again get EEXIST, and see: netdevsim: probe of netdevsim0 failed with error -17 in the logs. When we remove the loop again the nsim_dev_probe() and nsim_dev_remove() become a wrapper of nsim_dev_create() and nsim_dev_destroy(). Remove this layer of indirection. Fixes: d31e95585ca6 ("Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net") Signed-off-by: Jakub Kicinski Acked-by: Jiri Pirko Signed-off-by: David S. Miller

Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net

2019-11-02T20:54:56Z

The only slightly tricky merge conflict was the netdevsim because the mutex locking fix overlapped a lot of driver reload reorganization. The rest were (relatively) trivial in nature. Signed-off-by: David S. Miller

netdevsim: Fix use-after-free during device dismantle

2019-10-31T19:35:14Z

Commit da58f90f11f5 ("netdevsim: Add devlink-trap support") added delayed work to netdevsim that periodically iterates over the registered netdevsim ports and reports various packet traps via devlink. While the delayed work takes the 'port_list_lock' mutex to protect against concurrent addition / deletion of ports, during device creation / dismantle ports are added / deleted without this lock, which can result in a use-after-free [1]. Fix this by making sure that the ports list is always modified under the lock. [1] [ 59.205543] ================================================================== [ 59.207748] BUG: KASAN: use-after-free in nsim_dev_trap_report_work+0xa67/0xad0 [ 59.210247] Read of size 8 at addr ffff8883cbdd3398 by task kworker/3:1/38 [ 59.212584] [ 59.213148] CPU: 3 PID: 38 Comm: kworker/3:1 Not tainted 5.4.0-rc3-custom-16119-ge6abb5f0261e #2013 [ 59.215896] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS ?-20180724_192412-buildhw-07.phx2.fedoraproject.org-1.fc29 04/01/2014 [ 59.218384] Workqueue: events nsim_dev_trap_report_work [ 59.219428] Call Trace: [ 59.219924] dump_stack+0xa9/0x10e [ 59.220623] print_address_description.constprop.4+0x21/0x340 [ 59.221976] ? vprintk_func+0x66/0x240 [ 59.222752] __kasan_report.cold.8+0x78/0x91 [ 59.223602] ? nsim_dev_trap_report_work+0xa67/0xad0 [ 59.224603] kasan_report+0xe/0x20 [ 59.225296] nsim_dev_trap_report_work+0xa67/0xad0 [ 59.226435] ? rcu_read_lock_sched_held+0xaf/0xe0 [ 59.227512] ? trace_event_raw_event_rcu_quiescent_state_report+0x360/0x360 [ 59.228851] process_one_work+0x98f/0x1760 [ 59.229684] ? pwq_dec_nr_in_flight+0x330/0x330 [ 59.230656] worker_thread+0x91/0xc40 [ 59.231587] ? process_one_work+0x1760/0x1760 [ 59.232451] kthread+0x34a/0x410 [ 59.233104] ? __kthread_queue_delayed_work+0x240/0x240 [ 59.234141] ret_from_fork+0x3a/0x50 [ 59.234982] [ 59.235371] Allocated by task 187: [ 59.236189] save_stack+0x19/0x80 [ 59.236853] __kasan_kmalloc.constprop.5+0xc1/0xd0 [ 59.237822] kmem_cache_alloc_trace+0x14c/0x380 [ 59.238769] __nsim_dev_port_add+0xaf/0x5c0 [ 59.239627] nsim_dev_probe+0x4fc/0x1140 [ 59.240550] really_probe+0x264/0xc00 [ 59.241418] driver_probe_device+0x208/0x2e0 [ 59.242255] __device_attach_driver+0x215/0x2d0 [ 59.243150] bus_for_each_drv+0x154/0x1d0 [ 59.243944] __device_attach+0x1ba/0x2b0 [ 59.244923] bus_probe_device+0x1dd/0x290 [ 59.245805] device_add+0xbac/0x1550 [ 59.246528] new_device_store+0x1f4/0x400 [ 59.247306] bus_attr_store+0x7b/0xa0 [ 59.248047] sysfs_kf_write+0x10f/0x170 [ 59.248941] kernfs_fop_write+0x283/0x430 [ 59.249843] __vfs_write+0x81/0x100 [ 59.250546] vfs_write+0x1ce/0x510 [ 59.251190] ksys_write+0x104/0x200 [ 59.251873] do_syscall_64+0xa4/0x4e0 [ 59.252642] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 59.253837] [ 59.254203] Freed by task 187: [ 59.254811] save_stack+0x19/0x80 [ 59.255463] __kasan_slab_free+0x125/0x170 [ 59.256265] kfree+0x100/0x440 [ 59.256870] nsim_dev_remove+0x98/0x100 [ 59.257651] nsim_bus_remove+0x16/0x20 [ 59.258382] device_release_driver_internal+0x20b/0x4d0 [ 59.259588] bus_remove_device+0x2e9/0x5a0 [ 59.260551] device_del+0x410/0xad0 [ 59.263777] device_unregister+0x26/0xc0 [ 59.264616] nsim_bus_dev_del+0x16/0x60 [ 59.265381] del_device_store+0x2d6/0x3c0 [ 59.266295] bus_attr_store+0x7b/0xa0 [ 59.267192] sysfs_kf_write+0x10f/0x170 [ 59.267960] kernfs_fop_write+0x283/0x430 [ 59.268800] __vfs_write+0x81/0x100 [ 59.269551] vfs_write+0x1ce/0x510 [ 59.270252] ksys_write+0x104/0x200 [ 59.270910] do_syscall_64+0xa4/0x4e0 [ 59.271680] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 59.272812] [ 59.273211] The buggy address belongs to the object at ffff8883cbdd3200 [ 59.273211] which belongs to the cache kmalloc-512 of size 512 [ 59.275838] The buggy address is located 408 bytes inside of [ 59.275838] 512-byte region [ffff8883cbdd3200, ffff8883cbdd3400) [ 59.278151] The buggy address belongs to the page: [ 59.279215] page:ffffea000f2f7400 refcount:1 mapcount:0 mapping:ffff8883ecc0ce00 index:0x0 compound_mapcount: 0 [ 59.281449] flags: 0x200000000010200(slab|head) [ 59.282356] raw: 0200000000010200 ffffea000f2f3a08 ffffea000f2fd608 ffff8883ecc0ce00 [ 59.283949] raw: 0000000000000000 0000000000150015 00000001ffffffff 0000000000000000 [ 59.285608] page dumped because: kasan: bad access detected [ 59.286981] [ 59.287337] Memory state around the buggy address: [ 59.288310] ffff8883cbdd3280: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 59.289763] ffff8883cbdd3300: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 59.291452] >ffff8883cbdd3380: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 59.292945] ^ [ 59.293815] ffff8883cbdd3400: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 59.295220] ffff8883cbdd3480: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 59.296872] ================================================================== Fixes: da58f90f11f5 ("netdevsim: Add devlink-trap support") Signed-off-by: Ido Schimmel Reported-by: syzbot+9ed8f68ab30761f3678e@syzkaller.appspotmail.com Acked-by: Jakub Kicinski Signed-off-by: David S. Miller

netdevsim: implement couple of testing devlink health reporters

2019-10-12T04:02:30Z

Implement "empty" and "dummy" reporters. The first one is really simple and does nothing. The other one has debugfs files to trigger breakage and it is able to do recovery. The ops also implement dummy fmsg content. Signed-off-by: Jiri Pirko Signed-off-by: David S. Miller

netdevsim: fix spelling mistake "forbidded" -> "forbid"

2019-10-08T18:47:54Z

There is a spelling mistake in a NL_SET_ERR_MSG_MOD message. Fix it. Signed-off-by: Colin Ian King Signed-off-by: Jakub Kicinski

netdevsim: implement devlink dev_info op

2019-10-07T13:11:07Z

Do simple dev_info devlink operation implementation which only fills up the driver name. Signed-off-by: Jiri Pirko Signed-off-by: David S. Miller