kernel/linux.git/net/bluetooth/af_bluetooth.c, branch linux-4.20.y

Bluetooth: Fix locking in bt_accept_enqueue() for BH context

2019-03-10T06:10:16+00:00

commit c4f5627f7eeecde1bb6b646d8c0907b96dc2b2a6 upstream. With commit e16337622016 ("Bluetooth: Handle bt_accept_enqueue() socket atomically") lock_sock[_nested]() is used to acquire the socket lock before manipulating the socket. lock_sock[_nested]() may block, which is problematic since bt_accept_enqueue() can be called in bottom half context (e.g. from rfcomm_connect_ind()): [] __might_sleep+0x4c/0x80 [] lock_sock_nested+0x24/0x58 [] bt_accept_enqueue+0x48/0xd4 [bluetooth] [] rfcomm_connect_ind+0x190/0x218 [rfcomm] Add a parameter to bt_accept_enqueue() to indicate whether the function is called from BH context, and acquire the socket lock with bh_lock_sock_nested() if that's the case. Also adapt all callers of bt_accept_enqueue() to pass the new parameter: - l2cap_sock_new_connection_cb() - uses lock_sock() to lock the parent socket => process context - rfcomm_connect_ind() - acquires the parent socket lock with bh_lock_sock() => BH context - __sco_chan_add() - called from sco_chan_add(), which is called from sco_connect(). parent is NULL, hence bt_accept_enqueue() isn't called in this code path and we can ignore it - also called from sco_conn_ready(). uses bh_lock_sock() to acquire the parent lock => BH context Fixes: e16337622016 ("Bluetooth: Handle bt_accept_enqueue() socket atomically") Signed-off-by: Matthias Kaehlcke Reviewed-by: Douglas Anderson Signed-off-by: Marcel Holtmann Cc: stable@vger.kernel.org Signed-off-by: Greg Kroah-Hartman

Bluetooth: Use lock_sock_nested in bt_accept_enqueue

2018-07-18T12:10:29+00:00

Fixes this warning that was provoked by a pairing: [60258.016221] WARNING: possible recursive locking detected [60258.021558] 4.15.0-RD1812-BSP #1 Tainted: G O [60258.027146] -------------------------------------------- [60258.032464] kworker/u5:0/70 is trying to acquire lock: [60258.037609] (sk_lock-AF_BLUETOOTH-BTPROTO_L2CAP){+.+.}, at: [<87759073>] bt_accept_enqueue+0x3c/0x74 [60258.046863] [60258.046863] but task is already holding lock: [60258.052704] (sk_lock-AF_BLUETOOTH-BTPROTO_L2CAP){+.+.}, at: [] l2cap_sock_new_connection_cb+0x1c/0x88 [60258.062905] [60258.062905] other info that might help us debug this: [60258.069441] Possible unsafe locking scenario: [60258.069441] [60258.075368] CPU0 [60258.077821] ---- [60258.080272] lock(sk_lock-AF_BLUETOOTH-BTPROTO_L2CAP); [60258.085510] lock(sk_lock-AF_BLUETOOTH-BTPROTO_L2CAP); [60258.090748] [60258.090748] *** DEADLOCK *** [60258.090748] [60258.096676] May be due to missing lock nesting notation [60258.096676] [60258.103472] 5 locks held by kworker/u5:0/70: [60258.107747] #0: ((wq_completion)%shdev->name#2){+.+.}, at: [<9460d092>] process_one_work+0x130/0x4fc [60258.117263] #1: ((work_completion)(&hdev->rx_work)){+.+.}, at: [<9460d092>] process_one_work+0x130/0x4fc [60258.126942] #2: (&conn->chan_lock){+.+.}, at: [<7877c8c3>] l2cap_connect+0x80/0x4f8 [60258.134806] #3: (&chan->lock/2){+.+.}, at: [<2e16c724>] l2cap_connect+0x8c/0x4f8 [60258.142410] #4: (sk_lock-AF_BLUETOOTH-BTPROTO_L2CAP){+.+.}, at: [] l2cap_sock_new_connection_cb+0x1c/0x88 [60258.153043] [60258.153043] stack backtrace: [60258.157413] CPU: 1 PID: 70 Comm: kworker/u5:0 Tainted: G O 4.15.0-RD1812-BSP #1 [60258.165945] Hardware name: Freescale i.MX6 Quad/DualLite (Device Tree) [60258.172485] Workqueue: hci0 hci_rx_work [60258.176331] Backtrace: [60258.178797] [<8010c9fc>] (dump_backtrace) from [<8010ccbc>] (show_stack+0x18/0x1c) [60258.186379] r7:80e55fe4 r6:80e55fe4 r5:20050093 r4:00000000 [60258.192058] [<8010cca4>] (show_stack) from [<809864e8>] (dump_stack+0xb0/0xdc) [60258.199301] [<80986438>] (dump_stack) from [<8016ecc8>] (__lock_acquire+0xffc/0x11d4) [60258.207144] r9:5e2bb019 r8:630f974c r7:ba8a5940 r6:ba8a5ed8 r5:815b5220 r4:80fa081c [60258.214901] [<8016dccc>] (__lock_acquire) from [<8016f620>] (lock_acquire+0x78/0x98) [60258.222655] r10:00000040 r9:00000040 r8:808729f0 r7:00000001 r6:00000000 r5:60050013 [60258.230491] r4:00000000 [60258.233045] [<8016f5a8>] (lock_acquire) from [<806ee974>] (lock_sock_nested+0x64/0x88) [60258.240970] r7:00000000 r6:b796e870 r5:00000001 r4:b796e800 [60258.246643] [<806ee910>] (lock_sock_nested) from [<808729f0>] (bt_accept_enqueue+0x3c/0x74) [60258.255004] r8:00000001 r7:ba7d3c00 r6:ba7d3ea4 r5:ba7d2000 r4:b796e800 [60258.261717] [<808729b4>] (bt_accept_enqueue) from [<808aa39c>] (l2cap_sock_new_connection_cb+0x68/0x88) [60258.271117] r5:b796e800 r4:ba7d2000 [60258.274708] [<808aa334>] (l2cap_sock_new_connection_cb) from [<808a294c>] (l2cap_connect+0x190/0x4f8) [60258.283933] r5:00000001 r4:ba6dce00 [60258.287524] [<808a27bc>] (l2cap_connect) from [<808a4a14>] (l2cap_recv_frame+0x744/0x2cf8) [60258.295800] r10:ba6dcf24 r9:00000004 r8:b78d8014 r7:00000004 r6:bb05d000 r5:00000004 [60258.303635] r4:bb05d008 [60258.306183] [<808a42d0>] (l2cap_recv_frame) from [<808a7808>] (l2cap_recv_acldata+0x210/0x214) [60258.314805] r10:b78e7800 r9:bb05d960 r8:00000001 r7:bb05d000 r6:0000000c r5:b7957a80 [60258.322641] r4:ba6dce00 [60258.325188] [<808a75f8>] (l2cap_recv_acldata) from [<8087630c>] (hci_rx_work+0x35c/0x4e8) [60258.333374] r6:80e5743c r5:bb05d7c8 r4:b7957a80 [60258.338004] [<80875fb0>] (hci_rx_work) from [<8013dc7c>] (process_one_work+0x1a4/0x4fc) [60258.346018] r10:00000001 r9:00000000 r8:baabfef8 r7:ba997500 r6:baaba800 r5:baaa5d00 [60258.353853] r4:bb05d7c8 [60258.356401] [<8013dad8>] (process_one_work) from [<8013e028>] (worker_thread+0x54/0x5cc) [60258.364503] r10:baabe038 r9:baaba834 r8:80e05900 r7:00000088 r6:baaa5d18 r5:baaba800 [60258.372338] r4:baaa5d00 [60258.374888] [<8013dfd4>] (worker_thread) from [<801448f8>] (kthread+0x134/0x160) [60258.382295] r10:ba8310b8 r9:bb07dbfc r8:8013dfd4 r7:baaa5d00 r6:00000000 r5:baaa8ac0 [60258.390130] r4:ba831080 [60258.392682] [<801447c4>] (kthread) from [<801080b4>] (ret_from_fork+0x14/0x20) [60258.399915] r10:00000000 r9:00000000 r8:00000000 r7:00000000 r6:00000000 r5:801447c4 [60258.407751] r4:baaa8ac0 r3:baabe000 Signed-off-by: Philipp Puschmann Signed-off-by: Marcel Holtmann

Revert changes to convert to ->poll_mask() and aio IOCB_CMD_POLL

2018-06-28T17:40:47+00:00

The poll() changes were not well thought out, and completely unexplained. They also caused a huge performance regression, because "->poll()" was no longer a trivial file operation that just called down to the underlying file operations, but instead did at least two indirect calls. Indirect calls are sadly slow now with the Spectre mitigation, but the performance problem could at least be largely mitigated by changing the "->get_poll_head()" operation to just have a per-file-descriptor pointer to the poll head instead. That gets rid of one of the new indirections. But that doesn't fix the new complexity that is completely unwarranted for the regular case. The (undocumented) reason for the poll() changes was some alleged AIO poll race fixing, but we don't make the common case slower and more complex for some uncommon special case, so this all really needs way more explanations and most likely a fundamental redesign. [ This revert is a revert of about 30 different commits, not reverted individually because that would just be unnecessarily messy - Linus ] Cc: Al Viro Cc: Christoph Hellwig Signed-off-by: Linus Torvalds

Merge branch 'work.aio-1' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs

2018-06-04T20:57:43+00:00

Pull aio updates from Al Viro: "Majority of AIO stuff this cycle. aio-fsync and aio-poll, mostly. The only thing I'm holding back for a day or so is Adam's aio ioprio - his last-minute fixup is trivial (missing stub in !CONFIG_BLOCK case), but let it sit in -next for decency sake..." * 'work.aio-1' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (46 commits) aio: sanitize the limit checking in io_submit(2) aio: fold do_io_submit() into callers aio: shift copyin of iocb into io_submit_one() aio_read_events_ring(): make a bit more readable aio: all callers of aio_{read,write,fsync,poll} treat 0 and -EIOCBQUEUED the same way aio: take list removal to (some) callers of aio_complete() aio: add missing break for the IOCB_CMD_FDSYNC case random: convert to ->poll_mask timerfd: convert to ->poll_mask eventfd: switch to ->poll_mask pipe: convert to ->poll_mask crypto: af_alg: convert to ->poll_mask net/rxrpc: convert to ->poll_mask net/iucv: convert to ->poll_mask net/phonet: convert to ->poll_mask net/nfc: convert to ->poll_mask net/caif: convert to ->poll_mask net/bluetooth: convert to ->poll_mask net/sctp: convert to ->poll_mask net/tipc: convert to ->poll_mask ...

net/bluetooth: convert to ->poll_mask

2018-05-26T07:16:44+00:00

Signed-off-by: Christoph Hellwig

bluetooth: switch to proc_create_seq_data

2018-05-16T05:24:30+00:00

And use proc private data directly instead of doing a detour through seq->private and private state. Signed-off-by: Christoph Hellwig

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

Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next

2018-01-31T22:31:10+00:00

Pull networking updates from David Miller: 1) Significantly shrink the core networking routing structures. Result of http://vger.kernel.org/~davem/seoul2017_netdev_keynote.pdf 2) Add netdevsim driver for testing various offloads, from Jakub Kicinski. 3) Support cross-chip FDB operations in DSA, from Vivien Didelot. 4) Add a 2nd listener hash table for TCP, similar to what was done for UDP. From Martin KaFai Lau. 5) Add eBPF based queue selection to tun, from Jason Wang. 6) Lockless qdisc support, from John Fastabend. 7) SCTP stream interleave support, from Xin Long. 8) Smoother TCP receive autotuning, from Eric Dumazet. 9) Lots of erspan tunneling enhancements, from William Tu. 10) Add true function call support to BPF, from Alexei Starovoitov. 11) Add explicit support for GRO HW offloading, from Michael Chan. 12) Support extack generation in more netlink subsystems. From Alexander Aring, Quentin Monnet, and Jakub Kicinski. 13) Add 1000BaseX, flow control, and EEE support to mvneta driver. From Russell King. 14) Add flow table abstraction to netfilter, from Pablo Neira Ayuso. 15) Many improvements and simplifications to the NFP driver bpf JIT, from Jakub Kicinski. 16) Support for ipv6 non-equal cost multipath routing, from Ido Schimmel. 17) Add resource abstration to devlink, from Arkadi Sharshevsky. 18) Packet scheduler classifier shared filter block support, from Jiri Pirko. 19) Avoid locking in act_csum, from Davide Caratti. 20) devinet_ioctl() simplifications from Al viro. 21) More TCP bpf improvements from Lawrence Brakmo. 22) Add support for onlink ipv6 route flag, similar to ipv4, from David Ahern. * git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next: (1925 commits) tls: Add support for encryption using async offload accelerator ip6mr: fix stale iterator net/sched: kconfig: Remove blank help texts openvswitch: meter: Use 64-bit arithmetic instead of 32-bit tcp_nv: fix potential integer overflow in tcpnv_acked r8169: fix RTL8168EP take too long to complete driver initialization. qmi_wwan: Add support for Quectel EP06 rtnetlink: enable IFLA_IF_NETNSID for RTM_NEWLINK ipmr: Fix ptrdiff_t print formatting ibmvnic: Wait for device response when changing MAC qlcnic: fix deadlock bug tcp: release sk_frag.page in tcp_disconnect ipv4: Get the address of interface correctly. net_sched: gen_estimator: fix lockdep splat net: macb: Handle HRESP error net/mlx5e: IPoIB, Fix copy-paste bug in flow steering refactoring ipv6: addrconf: break critical section in addrconf_verify_rtnl() ipv6: change route cache aging logic i40e/i40evf: Update DESC_NEEDED value to reflect larger value bnxt_en: cleanup DIM work on device shutdown ...

Bluetooth: Use common error handling code in bt_init()

2017-12-12T23:28:40+00:00

* Improve jump targets so that a bit of exception handling can be better reused at the end of this function. * Adjust five condition checks. This issue was detected by using the Coccinelle software. Signed-off-by: Markus Elfring Signed-off-by: Marcel Holtmann

net: annotate ->poll() instances

2017-11-27T21:20:04+00:00

Signed-off-by: Al Viro