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author | Peter Hurley <peter@hurleysoftware.com> | 2014-02-10 02:59:06 +0100 |
---|---|---|
committer | Marcel Holtmann <marcel@holtmann.org> | 2014-02-14 22:39:29 +0100 |
commit | 960603a54aa0d5f4f1c4f1037bcaee571d03cb1e (patch) | |
tree | e226fbc1a87886de9b8fdc821d6f39a4d67ee40a /net/bluetooth/rfcomm/tty.c | |
parent | Bluetooth: Fix racy acquire of rfcomm_dev reference (diff) | |
download | linux-960603a54aa0d5f4f1c4f1037bcaee571d03cb1e.tar.xz linux-960603a54aa0d5f4f1c4f1037bcaee571d03cb1e.zip |
Bluetooth: Exclude released devices from RFCOMMGETDEVLIST ioctl
When enumerating RFCOMM devices in the rfcomm_dev_list, holding
the rfcomm_dev_lock only guarantees the existence of the enumerated
rfcomm_dev in memory, and not safe access to its state. Testing
the device state (such as RFCOMM_TTY_RELEASED) does not guarantee
the device will remain in that state for the subsequent access
to the rfcomm_dev's fields, nor guarantee that teardown has not
commenced.
Obtain an rfcomm_dev reference for the duration of rfcomm_dev
access.
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Tested-By: Alexander Holler <holler@ahsoftware.de>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Diffstat (limited to 'net/bluetooth/rfcomm/tty.c')
-rw-r--r-- | net/bluetooth/rfcomm/tty.c | 3 |
1 files changed, 2 insertions, 1 deletions
diff --git a/net/bluetooth/rfcomm/tty.c b/net/bluetooth/rfcomm/tty.c index 7cf193f0eea7..b385d9985656 100644 --- a/net/bluetooth/rfcomm/tty.c +++ b/net/bluetooth/rfcomm/tty.c @@ -468,7 +468,7 @@ static int rfcomm_get_dev_list(void __user *arg) spin_lock(&rfcomm_dev_lock); list_for_each_entry(dev, &rfcomm_dev_list, list) { - if (test_bit(RFCOMM_TTY_RELEASED, &dev->flags)) + if (!tty_port_get(&dev->port)) continue; (di + n)->id = dev->id; (di + n)->flags = dev->flags; @@ -476,6 +476,7 @@ static int rfcomm_get_dev_list(void __user *arg) (di + n)->channel = dev->channel; bacpy(&(di + n)->src, &dev->src); bacpy(&(di + n)->dst, &dev->dst); + tty_port_put(&dev->port); if (++n >= dev_num) break; } |