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| author | Christian Lamparter <chunkeey@googlemail.com> | 2016-09-21 18:49:36 +0200 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2016-09-21 18:58:58 +0200 |
| commit | 6ee6d1cb391ca85b419f8d18bdfb1f020a5e859c (patch) | |
| tree | 1b7f913afbfcf6df95aeb2ca6f7a3c4762dc90e9 /drivers/net/wireless/ath/carl9170 | |
| parent | 9c4a45b17e094a090e96beb1138e34c2a10c6b8c (diff) | |
| download | lwn-6ee6d1cb391ca85b419f8d18bdfb1f020a5e859c.tar.gz lwn-6ee6d1cb391ca85b419f8d18bdfb1f020a5e859c.zip | |
carl9170: fix debugfs crashes
Ben Greear reported:
> I see lots of instability as soon as I load up the carl9710 NIC.
> My application is going to be poking at it's debugfs files...
>
> BUG: KASAN: slab-out-of-bounds in carl9170_debugfs_read+0xd5/0x2a0
> [carl9170] at addr 0xffff8801bc1208b0
> Read of size 8 by task btserver/5888
> =======================================================================
> BUG kmalloc-256 (Tainted: G W ): kasan: bad access detected
> -----------------------------------------------------------------------
>
> INFO: Allocated in seq_open+0x50/0x100 age=2690 cpu=2 pid=772
>...
This breakage was caused by the introduction of intermediate
fops in debugfs by commit 9fd4dcece43a
("debugfs: prevent access to possibly dead file_operations at file open")
Thankfully, the original/real fops are still available in d_fsdata.
Reported-by: Ben Greear <greearb@candelatech.com>
Signed-off-by: Christian Lamparter <chunkeey@gmail.com>
Cc: stable <stable@vger.kernel.org> # 4.7+
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/net/wireless/ath/carl9170')
| -rw-r--r-- | drivers/net/wireless/ath/carl9170/debug.c | 6 |
1 files changed, 4 insertions, 2 deletions
diff --git a/drivers/net/wireless/ath/carl9170/debug.c b/drivers/net/wireless/ath/carl9170/debug.c index 6808db433283..ec3a64e5d2bb 100644 --- a/drivers/net/wireless/ath/carl9170/debug.c +++ b/drivers/net/wireless/ath/carl9170/debug.c @@ -75,7 +75,8 @@ static ssize_t carl9170_debugfs_read(struct file *file, char __user *userbuf, if (!ar) return -ENODEV; - dfops = container_of(file->f_op, struct carl9170_debugfs_fops, fops); + dfops = container_of(debugfs_real_fops(file), + struct carl9170_debugfs_fops, fops); if (!dfops->read) return -ENOSYS; @@ -127,7 +128,8 @@ static ssize_t carl9170_debugfs_write(struct file *file, if (!ar) return -ENODEV; - dfops = container_of(file->f_op, struct carl9170_debugfs_fops, fops); + dfops = container_of(debugfs_real_fops(file), + struct carl9170_debugfs_fops, fops); if (!dfops->write) return -ENOSYS; |