diff options
| author | Mathieu Desnoyers <mathieu.desnoyers@efficios.com> | 2011-11-30 13:34:15 -0500 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@suse.de> | 2011-12-01 09:37:47 -0800 |
| commit | e5f7787388da7562b955a36b46e909e500a5974b (patch) | |
| tree | ab75c8df8a59c7f6d348f143700921bb9bf70fcb | |
| parent | 2f8e0b31ad257bca9ff5dda9fdfdcc98d38d97f8 (diff) | |
lttng lib: ring buffer remove duplicate null pointer
* Dan Carpenter <dan.carpenter@oracle.com> wrote:
> The patch c844b2f5cfea: "lttng lib: ring buffer" from Nov 28, 2011,
> leads to the following Smatch complaint:
>
> drivers/staging/lttng/lib/ringbuffer/ring_buffer_mmap.c +33
> +lib_ring_buffer_fault()
> warn: variable dereferenced before check 'buf' (see line 26)
>
> drivers/staging/lttng/lib/ringbuffer/ring_buffer_mmap.c
> 25 struct lib_ring_buffer *buf = vma->vm_private_data;
> 26 struct channel *chan = buf->backend.chan;
> ^^^^^^^^^^^^^^^^^
> Dereference.
>
> 27 const struct lib_ring_buffer_config *config = chan->backend.config;
> 28 pgoff_t pgoff = vmf->pgoff;
> 29 struct page **page;
> 30 void **virt;
> 31 unsigned long offset, sb_bindex;
> 32
> 33 if (!buf)
> ^^^^
> Check.
>
> 34 return VM_FAULT_OOM;
> 35
This check is performed at mapping setup time in
lib_ring_buffer_mmap_buf() already, so we can safely remove this
duplicata.
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
| -rw-r--r-- | drivers/staging/lttng/lib/ringbuffer/ring_buffer_mmap.c | 3 |
1 files changed, 0 insertions, 3 deletions
diff --git a/drivers/staging/lttng/lib/ringbuffer/ring_buffer_mmap.c b/drivers/staging/lttng/lib/ringbuffer/ring_buffer_mmap.c index 68221ee9a870..cf374348d907 100644 --- a/drivers/staging/lttng/lib/ringbuffer/ring_buffer_mmap.c +++ b/drivers/staging/lttng/lib/ringbuffer/ring_buffer_mmap.c @@ -30,9 +30,6 @@ static int lib_ring_buffer_fault(struct vm_area_struct *vma, struct vm_fault *vm void **virt; unsigned long offset, sb_bindex; - if (!buf) - return VM_FAULT_OOM; - /* * Verify that faults are only done on the range of pages owned by the * reader. |