diff options
author | Kai Vehmanen <kai.vehmanen@linux.intel.com> | 2022-10-18 15:13:32 +0300 |
---|---|---|
committer | Mark Brown <broonie@kernel.org> | 2022-10-18 21:17:21 +0100 |
commit | af6514f2f3828dc39c96cd4686ef5c9d8368626f (patch) | |
tree | e44593d492e3f66bce9ac8133054a7f6d5db7dfa /sound | |
parent | b4dd2e3758709aa8a2abd1ac34c56bd09b980039 (diff) | |
download | lwn-af6514f2f3828dc39c96cd4686ef5c9d8368626f.tar.gz lwn-af6514f2f3828dc39c96cd4686ef5c9d8368626f.zip |
ASoC: SOF: ipc4-mtrace: protect per-core nodes against multiple open
Add protection against multiple open of the mtrace/coreN debugfs
nodes. This is not supported in the implementation, and this will
show up as unexpected behaviour of the interface, and potential
use of already freed memory.
Fixes: f4ea22f7aa75 ("ASoC: SOF: ipc4: Add support for mtrace log extraction")
Signed-off-by: Kai Vehmanen <kai.vehmanen@linux.intel.com>
Reviewed-by: Péter Ujfalusi <peter.ujfalusi@linux.intel.com>
Reviewed-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Reviewed-by: Ranjani Sridharan <ranjani.sridharan@linux.intel.com>
Link: https://lore.kernel.org/r/20221018121332.20802-1-peter.ujfalusi@linux.intel.com
Signed-off-by: Mark Brown <broonie@kernel.org>
Diffstat (limited to 'sound')
-rw-r--r-- | sound/soc/sof/ipc4-mtrace.c | 20 |
1 files changed, 18 insertions, 2 deletions
diff --git a/sound/soc/sof/ipc4-mtrace.c b/sound/soc/sof/ipc4-mtrace.c index 9c7080041d08..70dea8ae706e 100644 --- a/sound/soc/sof/ipc4-mtrace.c +++ b/sound/soc/sof/ipc4-mtrace.c @@ -108,6 +108,7 @@ struct sof_mtrace_core_data { int id; u32 slot_offset; void *log_buffer; + struct mutex buffer_lock; /* for log_buffer alloc/free */ u32 host_read_ptr; u32 dsp_write_ptr; /* pos update IPC arrived before the slot offset is known, queried */ @@ -128,14 +129,22 @@ static int sof_ipc4_mtrace_dfs_open(struct inode *inode, struct file *file) struct sof_mtrace_core_data *core_data = inode->i_private; int ret; + mutex_lock(&core_data->buffer_lock); + + if (core_data->log_buffer) { + ret = -EBUSY; + goto out; + } + ret = debugfs_file_get(file->f_path.dentry); if (unlikely(ret)) - return ret; + goto out; core_data->log_buffer = kmalloc(SOF_MTRACE_SLOT_SIZE, GFP_KERNEL); if (!core_data->log_buffer) { debugfs_file_put(file->f_path.dentry); - return -ENOMEM; + ret = -ENOMEM; + goto out; } ret = simple_open(inode, file); @@ -144,6 +153,9 @@ static int sof_ipc4_mtrace_dfs_open(struct inode *inode, struct file *file) debugfs_file_put(file->f_path.dentry); } +out: + mutex_unlock(&core_data->buffer_lock); + return ret; } @@ -280,7 +292,10 @@ static int sof_ipc4_mtrace_dfs_release(struct inode *inode, struct file *file) debugfs_file_put(file->f_path.dentry); + mutex_lock(&core_data->buffer_lock); kfree(core_data->log_buffer); + core_data->log_buffer = NULL; + mutex_unlock(&core_data->buffer_lock); return 0; } @@ -563,6 +578,7 @@ static int ipc4_mtrace_init(struct snd_sof_dev *sdev) struct sof_mtrace_core_data *core_data = &priv->cores[i]; init_waitqueue_head(&core_data->trace_sleep); + mutex_init(&core_data->buffer_lock); core_data->sdev = sdev; core_data->id = i; } |