[Mesa-stable] [Mesa-dev] [PATCH] gallium/rtasm: handle mmap failures appropriately

[Jakob Bornecrantz]

On Mon, Jan 27, 2014 at 12:57 PM, Emil Velikov <emil.l.velikov at gmail.com> wrote:
> Ping :)
>
> On 19/01/14 23:53, Emil Velikov wrote:
>> For a variety of reasons mmap (selinux and pax to name
>> a few) and can fail and with current code. This will
>> result in a crash in the driver, if not worse.
>>
>> This has been the case since the inception of the
>> gallium copy of rtasm.
>>
>> Cc: 9.1 9.2 10.0 <mesa-stable at lists.freedesktop.org>
>> Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=73473
>> Signed-off-by: Emil Velikov <emil.l.velikov at gmail.com>
>> ---
>> v2: droped the selinux part, leaving only the crucial mmap check
>>
>> Gents can someone take a look at this trivial patch.
>>
>> Cheers,
>> Emil

Reviewed-by: Jakob Bornecrantz <jakob at vmware.com>

>> ---
>>  src/gallium/auxiliary/rtasm/rtasm_execmem.c | 10 +++++++---
>>  1 file changed, 7 insertions(+), 3 deletions(-)
>>
>> diff --git a/src/gallium/auxiliary/rtasm/rtasm_execmem.c b/src/gallium/auxiliary/rtasm/rtasm_execmem.c
>> index edc1b66..8c3dbef 100644
>> --- a/src/gallium/auxiliary/rtasm/rtasm_execmem.c
>> +++ b/src/gallium/auxiliary/rtasm/rtasm_execmem.c
>> @@ -69,7 +69,7 @@ static struct mem_block *exec_heap = NULL;
>>  static unsigned char *exec_mem = NULL;
>>
>>
>> -static void
>> +static int
>>  init_heap(void)
>>  {
>>     if (!exec_heap)
>> @@ -79,6 +79,8 @@ init_heap(void)
>>        exec_mem = (unsigned char *) mmap(0, EXEC_HEAP_SIZE,
>>                                       PROT_EXEC | PROT_READ | PROT_WRITE,
>>                                       MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
>> +
>> +   return (exec_mem != MAP_FAILED);
>>  }
>>
>>
>> @@ -90,7 +92,8 @@ rtasm_exec_malloc(size_t size)
>>
>>     pipe_mutex_lock(exec_mutex);
>>
>> -   init_heap();
>> +   if (!init_heap())
>> +      goto bail;
>>
>>     if (exec_heap) {
>>        size = (size + 31) & ~31;  /* next multiple of 32 bytes */
>> @@ -101,7 +104,8 @@ rtasm_exec_malloc(size_t size)
>>        addr = exec_mem + block->ofs;
>>     else
>>        debug_printf("rtasm_exec_malloc failed\n");
>> -
>> +
>> +bail:
>>     pipe_mutex_unlock(exec_mutex);
>>
>>     return addr;
>>