From: Guangming Cao <Guangming.Cao@xxxxxxxxxxxx> > Am 08.10.21 um 09:54 schrieb guangming.cao@xxxxxxxxxxxx: > > From: Guangming Cao <Guangming.Cao@xxxxxxxxxxxx> > > > > Because dma-buf.name can be freed in func: "dma_buf_set_name", > > so, we need to acquire lock first before we read/write dma_buf.name > > to prevent Use After Free(UAF) issue. > > > > Signed-off-by: Guangming Cao <Guangming.Cao@xxxxxxxxxxxx> > > Reviewed-by: Christian König <christian.koenig@xxxxxxx> > > Going to push that upstream if nobody else objects. > > Thanks, > Christian. I'm sorry to disturb you, actually I need this patch to solve our issues. Is there any question about it? seems it hasn't been merged into mainline. Thanks, Guangming. > > > --- > > drivers/dma-buf/dma-buf.c | 3 +++ > > 1 file changed, 3 insertions(+) > > > > diff --git a/drivers/dma-buf/dma-buf.c b/drivers/dma-buf/dma-buf.c > > index 511fe0d217a0..a7f6fd13a635 100644 > > --- a/drivers/dma-buf/dma-buf.c > > +++ b/drivers/dma-buf/dma-buf.c > > @@ -1372,6 +1372,8 @@ static int dma_buf_debug_show(struct seq_file *s, void *unused) > > if (ret) > > goto error_unlock; > > > > + > > + spin_lock(&buf_obj->name_lock); > > seq_printf(s, "%08zu\t%08x\t%08x\t%08ld\t%s\t%08lu\t%s\n", > > buf_obj->size, > > buf_obj->file->f_flags, buf_obj->file->f_mode, > > @@ -1379,6 +1381,7 @@ static int dma_buf_debug_show(struct seq_file *s, void *unused) > > buf_obj->exp_name, > > file_inode(buf_obj->file)->i_ino, > > buf_obj->name ?: ""); > > + spin_unlock(&buf_obj->name_lock); > > > > robj = buf_obj->resv; > > fence = dma_resv_excl_fence(robj);
