FROMGIT: dma-buf: acquire name lock before read/write dma_buf.name

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@mediatek.com>
Reviewed-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Christian König <christian.koenig@amd.com>
Link: https://lore.kernel.org/lkml/20211029021541.101157-1-guangming.cao@mediatek.com/T/

Bug: 205102180
(cherry picked from commit 8c0fd126263730c35927cc8445727afb79219a19
 https://cgit.freedesktop.org/drm/drm-misc)
Change-Id: I4ba911137ad9dae7682230245d2fa2a19f7c209f
Signed-off-by: Yunfei Wang <yf.wang@mediatek.com>
This commit is contained in:
Yunfei Wang
2021-11-04 19:10:12 +08:00
committed by Matthias Maennich
parent 1ba7c99bd3
commit 6cf4b65244

View File

@@ -1425,6 +1425,7 @@ static int dma_buf_debug_show(struct seq_file *s, void *unused)
if (ret) if (ret)
goto error_unlock; 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", seq_printf(s, "%08zu\t%08x\t%08x\t%08ld\t%s\t%08lu\t%s\n",
buf_obj->size, buf_obj->size,
buf_obj->file->f_flags, buf_obj->file->f_mode, buf_obj->file->f_flags, buf_obj->file->f_mode,
@@ -1432,6 +1433,7 @@ static int dma_buf_debug_show(struct seq_file *s, void *unused)
buf_obj->exp_name, buf_obj->exp_name,
file_inode(buf_obj->file)->i_ino, file_inode(buf_obj->file)->i_ino,
buf_obj->name ?: ""); buf_obj->name ?: "");
spin_unlock(&buf_obj->name_lock);
robj = buf_obj->resv; robj = buf_obj->resv;
while (true) { while (true) {