user/sven/linux.git/drivers/pps/pps.c, branch v3.4.89

pps: Fix a use-after free bug when unregistering a source.

2014-04-14T13:44:17Z

commit d953e0e837e65ecc1ddaa4f9560f7925878a0de6 upstream. Remove the cdev from the system (with cdev_del) *before* deallocating it (in pps_device_destruct, called via kobject_put from device_destroy). Also prevent deallocating a device with open file handles. A better long-term fix is probably to remove the cdev from the pps_device entirely, and instead have all devices reference one global cdev. Then the deallocation ordering becomes simpler. But that's more complex and invasive change, so we leave that for later. Signed-off-by: George Spelvin Acked-by: Rodolfo Giometti Signed-off-by: Greg Kroah-Hartman Signed-off-by: Ben Hutchings Cc: Qiang Huang Cc: Li Zefan Cc: Jianguo Wu Signed-off-by: Greg Kroah-Hartman

pps: Add pps_lookup_dev() function

2014-04-14T13:44:17Z

commit 513b032c98b4b9414aa4e9b4a315cb1bf0380101 upstream. The PPS serial line discipline wants to attach a PPS device to a tty without changing the tty code to add a struct pps_device * pointer. Since the number of PPS devices in a typical system is generally very low (n=1 is by far the most common), it's practical to search the entire list of allocated pps devices. (We capture the timestamp before the lookup, so the timing isn't affected.) It is a bit ugly that this function, which is part of the in-kernel PPS API, has to be in pps.c as opposed to kapi,c, but that's not something that affects users. Signed-off-by: George Spelvin Acked-by: Rodolfo Giometti Signed-off-by: Greg Kroah-Hartman Signed-off-by: Ben Hutchings Cc: Qiang Huang Cc: Li Zefan Cc: Jianguo Wu Signed-off-by: Greg Kroah-Hartman

pps: class_create() returns an ERR_PTR, not NULL

2012-03-05T23:49:43Z

class_create() never returns NULLs only ERR_PTRs. Signed-off-by: Dan Carpenter Cc: Rodolfo Giometti Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

pps: add kernel consumer support

2011-01-13T16:03:21Z

Add an optional feature of PPSAPI, kernel consumer support, which uses the added hardpps() function. Signed-off-by: Alexander Gordeev Acked-by: Rodolfo Giometti Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

pps: make idr lock a mutex and protect idr_pre_get

2011-01-13T16:03:20Z

Now pps_idr_lock is never used in interrupt context so we can replace spin_lock_irq/spin_unlock_irq with plain spin_lock/spin_unlock. But there is also a potential race condition when someone can steal an id which was allocated by idr_pre_get before it is used. So convert spin lock to mutex and protect the whole id generation process. Signed-off-by: Alexander Gordeev Cc: Rodolfo Giometti Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

pps: move idr stuff to pps.c

2011-01-13T16:03:20Z

Since now idr is only used to manage char device id's and not used in kernel API anymore it should be moved to pps.c. This also makes it possible to release id only at actual device freeing so nobody can register a pps device with the same id while our device is not freed yet. Signed-off-by: Alexander Gordeev Acked-by: Rodolfo Giometti Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

pps: convert printk/pr_* to dev_*

2011-01-13T16:03:19Z

Since we now have direct pointers to struct pps_device everywhere it's easy to use dev_* functions to print messages instead of plain printks. Where dev_* cannot be used printks are converted to pr_*. Signed-off-by: Alexander Gordeev Acked-by: Rodolfo Giometti Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

pps: access pps device by direct pointer

2011-01-13T16:03:19Z

Using device index as a pointer needs some unnecessary work to be done every time the pointer is needed (in irq handler for example). Using a direct pointer is much more easy (and safe as well). Signed-off-by: Alexander Gordeev Acked-by: Rodolfo Giometti Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

pps: fix race in PPS_FETCH handler

2011-01-13T16:03:19Z

There was a race in PPS_FETCH ioctl handler when several processes want to obtain PPS data simultaneously using sleeping PPS_FETCH. They all sleep most of the time in the system call. With the old approach when the first process waiting on the pps queue is waken up it makes new system call right away and zeroes pps->go. So other processes continue to sleep. This is a clear race condition because of the global 'go' variable. With the new approach pps->last_ev holds some value increasing at each PPS event. PPS_FETCH ioctl handler saves current value to the local variable at the very beginning so it can safely check that there is a new event by just comparing both variables. Signed-off-by: Alexander Gordeev Acked-by: Rodolfo Giometti Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

pps: declare variables where they are used in switch

2011-01-13T16:03:19Z

Move variable declarations where they are used in pps_cdev_ioctl. Signed-off-by: Alexander Gordeev Acked-by: Rodolfo Giometti Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds