[PATCH 5.8 012/118] habanalabs: prevent user buff overflow

Greg Kroah-Hartman
2020-09-21T16:43:18Z

From: Moti Haimovski <mhaimovski@habana.ai>

[ Upstream commit 6396feabf7a4104a4ddfecc00b8aac535c631a66 ]

This commit fixes a potential debugfs issue that may occur when
reading the clock gating mask into the user buffer since the
user buffer size was not taken into consideration.

Signed-off-by: Moti Haimovski <mhaimovski@habana.ai>
Reviewed-by: Oded Gabbay <oded.gabbay@gmail.com>
Signed-off-by: Oded Gabbay <oded.gabbay@gmail.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/misc/habanalabs/debugfs.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/misc/habanalabs/debugfs.c b/drivers/misc/habanalabs/debugfs.c
index 6c2b9cf45e831..650922061bdc7 100644
--- a/drivers/misc/habanalabs/debugfs.c
+++ b/drivers/misc/habanalabs/debugfs.c
@@ -982,7 +982,7 @@ static ssize_t hl_clk_gate_read(struct file *f, char __user *buf,
return 0;

sprintf(tmp_buf, "0x%llx\n", hdev->clock_gating_mask);
- rc = simple_read_from_buffer(buf, strlen(tmp_buf) + 1, ppos, tmp_buf,
+ rc = simple_read_from_buffer(buf, count, ppos, tmp_buf,
strlen(tmp_buf) + 1);

return rc;
--
2.25.1