lwn.git/drivers/bluetooth/hci_vhci.c, branch docs-5.2a

vfs: do bulk POLL* -> EPOLL* replacement

2018-02-11T22:34:03+00:00

This is the mindless scripted replacement of kernel use of POLL* variables as described by Al, done by this script: for V in IN OUT PRI ERR RDNORM RDBAND WRNORM WRBAND HUP RDHUP NVAL MSG; do L=`git grep -l -w POLL$V | grep -v '^t' | grep -v /um/ | grep -v '^sa' | grep -v '/poll.h$'|grep -v '^D'` for f in $L; do sed -i "-es/^$[^\"]*$$\$/\\1E\\2/" $f; done done with de-mangling cleanups yet to come. NOTE! On almost all architectures, the EPOLL* constants have the same values as the POLL* constants do. But they keyword here is "almost". For various bad reasons they aren't the same, and epoll() doesn't actually work quite correctly in some cases due to this on Sparc et al. The next patch from Al will sort out the final differences, and we should be all done. Scripted-by: Al Viro Signed-off-by: Linus Torvalds

the rest of drivers/*: annotate ->poll() instances

2017-11-28T16:06:58+00:00

Signed-off-by: Al Viro

networking: add and use skb_put_u8()

2017-06-16T15:48:40+00:00

Joe and Bjørn suggested that it'd be nicer to not have the cast in the fairly common case of doing *(u8 *)skb_put(skb, 1) = c; Add skb_put_u8() for this case, and use it across the code, using the following spatch: @@ expression SKB, C, S; typedef u8; identifier fn = {skb_put}; fresh identifier fn2 = fn ## "_u8"; @@ - *(u8 *)fn(SKB, S) = C; + fn2(SKB, C); Note that due to the "S", the spatch isn't perfect, it should have checked that S is 1, but there's also places that use a sizeof expression like sizeof(var) or sizeof(u8) etc. Turns out that nobody ever did something like *(u8 *)skb_put(skb, 2) = c; which would be wrong anyway since the second byte wouldn't be initialized. Suggested-by: Joe Perches Suggested-by: Bjørn Mork Signed-off-by: Johannes Berg Signed-off-by: David S. Miller

networking: make skb_put & friends return void pointers

2017-06-16T15:48:39+00:00

It seems like a historic accident that these return unsigned char *, and in many places that means casts are required, more often than not. Make these functions (skb_put, __skb_put and pskb_put) return void * and remove all the casts across the tree, adding a (u8 *) cast only where the unsigned char pointer was used directly, all done with the following spatch: @@ expression SKB, LEN; typedef u8; identifier fn = { skb_put, __skb_put }; @@ - *(fn(SKB, LEN)) + *(u8 *)fn(SKB, LEN) @@ expression E, SKB, LEN; identifier fn = { skb_put, __skb_put }; type T; @@ - E = ((T *)(fn(SKB, LEN))) + E = fn(SKB, LEN) which actually doesn't cover pskb_put since there are only three users overall. A handful of stragglers were converted manually, notably a macro in drivers/isdn/i4l/isdn_bsdcomp.c and, oddly enough, one of the many instances in net/bluetooth/hci_sock.c. In the former file, I also had to fix one whitespace problem spatch introduced. Signed-off-by: Johannes Berg Signed-off-by: David S. Miller

[iov_iter] new primitives - copy_from_iter_full() and friends

2016-12-05T19:33:36+00:00

copy_from_iter_full(), copy_from_iter_full_nocache() and csum_and_copy_from_iter_full() - counterparts of copy_from_iter() et.al., advancing iterator only in case of successful full copy and returning whether it had been successful or not. Convert some obvious users. *NOTE* - do not blindly assume that something is a good candidate for those unless you are sure that not advancing iov_iter in failure case is the right thing in this case. Anything that does short read/short write kind of stuff (or is in a loop, etc.) is unlikely to be a good one. Signed-off-by: Al Viro

miscdevice: Use module_misc_device() macro

2016-08-31T12:12:35+00:00

This patch removes module_init()/module_exit() from driver code by using module_misc_device() macro. All modules in this patch has a print statement which is removed when module_misc_device() macro is used. If undesirable this patch can be dropped entirely, this is the only purpose of making this as a separate patch. Signed-off-by: PrasannaKumar Muralidharan Signed-off-by: Greg Kroah-Hartman

Bluetooth: Rename HCI_BREDR into HCI_PRIMARY

2016-07-09T18:37:13+00:00

The HCI_BREDR naming is confusing since it actually stands for Primary Bluetooth Controller. Which is a term that has been used in the latest standard. However from a legacy point of view there only really have been Basic Rate (BR) and Enhanced Data Rate (EDR). Recent versions of Bluetooth introduced Low Energy (LE) and made this terminology a little bit confused since Dual Mode Controllers include BR/EDR and LE. To simplify this the name HCI_PRIMARY stands for the Primary Controller which can be a single mode or dual mode controller. Signed-off-by: Marcel Holtmann Signed-off-by: Johan Hedberg

Bluetooth: vhci: Fix race at creating hci device

2016-04-20T14:28:28+00:00

hci_vhci driver creates a hci device object dynamically upon each HCI_VENDOR_PKT write. Although it checks the already created object and returns an error, it's still racy and may build multiple hci_dev objects concurrently when parallel writes are performed, as the device tracks only a single hci_dev object. This patch introduces a mutex to protect against the concurrent device creations. Cc: Signed-off-by: Takashi Iwai Signed-off-by: Marcel Holtmann

Bluetooth: vhci: purge unhandled skbs

2016-04-08T17:22:46+00:00

The write handler allocates skbs and queues them into data->readq. Read side should read them, if there is any. If there is none, skbs should be dropped by hdev->flush. But this happens only if the device is HCI_UP, i.e. hdev->power_on work was triggered already. When it was not, skbs stay allocated in the queue when /dev/vhci is closed. So purge the queue in ->release. Program to reproduce: #include #include #include #include #include #include #include int main() { char buf[] = { 0xff, 0 }; struct iovec iov = { .iov_base = buf, .iov_len = sizeof(buf), }; int fd; while (1) { fd = open("/dev/vhci", O_RDWR); if (fd < 0) err(1, "open"); usleep(50); if (writev(fd, &iov, 1) < 0) err(1, "writev"); usleep(50); close(fd); } return 0; } Result: kmemleak: 4609 new suspected memory leaks unreferenced object 0xffff88059f4d5440 (size 232): comm "vhci", pid 1084, jiffies 4294912542 (age 37569.296s) hex dump (first 32 bytes): 20 f0 23 87 05 88 ff ff 20 f0 23 87 05 88 ff ff .#..... .#..... 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ backtrace: ... [] __alloc_skb+0x0/0x5a0 [] vhci_create_device+0x5c/0x580 [hci_vhci] [] vhci_write+0x306/0x4c8 [hci_vhci] Fixes: 23424c0d31 (Bluetooth: Add support creating virtual AMP controllers) Signed-off-by: Jiri Slaby Signed-off-by: Marcel Holtmann Cc: stable 3.13+

Bluetooth: vhci: fix open_timeout vs. hdev race

2016-04-08T17:16:38+00:00

Both vhci_get_user and vhci_release race with open_timeout work. They both contain cancel_delayed_work_sync, but do not test whether the work actually created hdev or not. Since the work can be in progress and _sync will wait for finishing it, we can have data->hdev allocated when cancel_delayed_work_sync returns. But the call sites do 'if (data->hdev)' *before* cancel_delayed_work_sync. As a result: * vhci_get_user allocates a second hdev and puts it into data->hdev. The former is leaked. * vhci_release does not release data->hdev properly as it thinks there is none. Fix both cases by moving the actual test *after* the call to cancel_delayed_work_sync. This can be hit by this program: #include #include #include #include #include #include #include #include int main(int argc, char **argv) { int fd; srand(time(NULL)); while (1) { const int delta = (rand() % 200 - 100) * 100; fd = open("/dev/vhci", O_RDWR); if (fd < 0) err(1, "open"); usleep(1000000 + delta); close(fd); } return 0; } And the result is: BUG: KASAN: use-after-free in skb_queue_tail+0x13e/0x150 at addr ffff88006b0c1228 Read of size 8 by task kworker/u13:1/32068 ============================================================================= BUG kmalloc-192 (Tainted: G E ): kasan: bad access detected ----------------------------------------------------------------------------- Disabling lock debugging due to kernel taint INFO: Allocated in vhci_open+0x50/0x330 [hci_vhci] age=260 cpu=3 pid=32040 ... kmem_cache_alloc_trace+0x150/0x190 vhci_open+0x50/0x330 [hci_vhci] misc_open+0x35b/0x4e0 chrdev_open+0x23b/0x510 ... INFO: Freed in vhci_release+0xa4/0xd0 [hci_vhci] age=9 cpu=2 pid=32040 ... __slab_free+0x204/0x310 vhci_release+0xa4/0xd0 [hci_vhci] ... INFO: Slab 0xffffea0001ac3000 objects=16 used=13 fp=0xffff88006b0c1e00 flags=0x5fffff80004080 INFO: Object 0xffff88006b0c1200 @offset=4608 fp=0xffff88006b0c0600 Bytes b4 ffff88006b0c11f0: 09 df 00 00 01 00 00 00 00 00 00 00 00 00 00 00 ................ Object ffff88006b0c1200: 00 06 0c 6b 00 88 ff ff 00 00 00 00 00 00 00 00 ...k............ Object ffff88006b0c1210: 10 12 0c 6b 00 88 ff ff 10 12 0c 6b 00 88 ff ff ...k.......k.... Object ffff88006b0c1220: c0 46 c2 6b 00 88 ff ff c0 46 c2 6b 00 88 ff ff .F.k.....F.k.... Object ffff88006b0c1230: 01 00 00 00 01 00 00 00 e0 ff ff ff 0f 00 00 00 ................ Object ffff88006b0c1240: 40 12 0c 6b 00 88 ff ff 40 12 0c 6b 00 88 ff ff @..k....@..k.... Object ffff88006b0c1250: 50 0d 6e a0 ff ff ff ff 00 02 00 00 00 00 ad de P.n............. Object ffff88006b0c1260: 00 00 00 00 00 00 00 00 ab 62 02 00 01 00 00 00 .........b...... Object ffff88006b0c1270: 90 b9 19 81 ff ff ff ff 38 12 0c 6b 00 88 ff ff ........8..k.... Object ffff88006b0c1280: 03 00 20 00 ff ff ff ff ff ff ff ff 00 00 00 00 .. ............. Object ffff88006b0c1290: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ Object ffff88006b0c12a0: 00 00 00 00 00 00 00 00 00 80 cd 3d 00 88 ff ff ...........=.... Object ffff88006b0c12b0: 00 20 00 00 00 00 00 00 00 00 00 00 00 00 00 00 . .............. Redzone ffff88006b0c12c0: bb bb bb bb bb bb bb bb ........ Padding ffff88006b0c13f8: 00 00 00 00 00 00 00 00 ........ CPU: 3 PID: 32068 Comm: kworker/u13:1 Tainted: G B E 4.4.6-0-default #1 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.8.1-0-g4adadbd-20151112_172657-sheep25 04/01/2014 Workqueue: hci0 hci_cmd_work [bluetooth] 00000000ffffffff ffffffff81926cfa ffff88006be37c68 ffff88006bc27180 ffff88006b0c1200 ffff88006b0c1234 ffffffff81577993 ffffffff82489320 ffff88006bc24240 0000000000000046 ffff88006a100000 000000026e51eb80 Call Trace: ... [] ? skb_queue_tail+0x13e/0x150 [] ? vhci_send_frame+0xac/0x100 [hci_vhci] [] ? hci_send_frame+0x188/0x320 [bluetooth] [] ? hci_cmd_work+0x115/0x310 [bluetooth] [] ? process_one_work+0x815/0x1340 [] ? worker_thread+0xe5/0x11f0 [] ? process_one_work+0x1340/0x1340 [] ? kthread+0x1c8/0x230 ... Memory state around the buggy address: ffff88006b0c1100: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff88006b0c1180: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff88006b0c1200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88006b0c1280: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc ffff88006b0c1300: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc Fixes: 23424c0d31 (Bluetooth: Add support creating virtual AMP controllers) Signed-off-by: Jiri Slaby Signed-off-by: Marcel Holtmann Cc: Dmitry Vyukov Cc: stable 3.13+