linux/drivers/net/netdevsim/dev.c, branch v5.6

netdevsim: fix ptr_ret.cocci warnings

2020-02-05T12:55:32Z

drivers/net/netdevsim/dev.c:937:1-3: WARNING: PTR_ERR_OR_ZERO can be used Use PTR_ERR_OR_ZERO rather than if(IS_ERR(...)) + PTR_ERR Generated by: scripts/coccinelle/api/ptr_ret.cocci Fixes: 6556ff32f12d ("netdevsim: use IS_ERR instead of IS_ERR_OR_NULL for debugfs") CC: Taehee Yoo Signed-off-by: kbuild test robot Signed-off-by: David S. Miller

netdevsim: use IS_ERR instead of IS_ERR_OR_NULL for debugfs

2020-02-03T23:32:20Z

Debugfs APIs return valid pointer or error pointer. it doesn't return NULL. So, using IS_ERR is enough, not using IS_ERR_OR_NULL. Reviewed-by: Jakub Kicinski Reported-by: kbuild test robot Reported-by: Dan Carpenter Signed-off-by: Taehee Yoo Signed-off-by: Jakub Kicinski

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

2020-02-03T23:32:20Z

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

netdevsim: fix panic in nsim_dev_take_snapshot_write()

2020-02-03T23:32:20Z

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

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

2020-01-19T21:10:04Z

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: rename and expand devlink-trap-netdevsim.rst

2020-01-11T01:07:00Z

Rename the trap-specific netdevimsim.rst file, and expand it to include documentation of all the devlink features currently implemented by the netdevsim driver code. Signed-off-by: Jacob Keller Cc: Jakub Kicinski Signed-off-by: David S. Miller

devlink: move devlink documentation to subfolder

2020-01-11T01:06:59Z

Combine the documentation for devlink into a subfolder, and provide an index.rst file that can be used to generally describe devlink. Signed-off-by: Jacob Keller 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