From: Tomer Tayar <ttayar@habana.ai>
Date: Thu, 1 Aug 2019 13:57:36 +0000 (+0000)
Subject: habanalabs: Avoid double free in error flow
X-Git-Url: http://git.cdn.openwrt.org/?a=commitdiff_plain;h=508c5849c62d009e03f37ad0f556071fac5112f0;p=openwrt%2Fstaging%2Fblogic.git

habanalabs: Avoid double free in error flow

In case kernel context init fails during device initialization, both
hl_ctx_put() and kfree() are called, ending with a double free of the
kernel context.
Calling kfree() is needed only when a failure happens between the
allocation of the kernel context and its initialization, so move it to
there and remove it from the error flow.

Signed-off-by: Tomer Tayar <ttayar@habana.ai>
Reviewed-by: Oded Gabbay <oded.gabbay@gmail.com>
Signed-off-by: Oded Gabbay <oded.gabbay@gmail.com>
---

diff --git a/drivers/misc/habanalabs/device.c b/drivers/misc/habanalabs/device.c
index 0c4894dd9c02..7a8f9d0b71b5 100644
--- a/drivers/misc/habanalabs/device.c
+++ b/drivers/misc/habanalabs/device.c
@@ -970,7 +970,8 @@ int hl_device_init(struct hl_device *hdev, struct class *hclass)
 	rc = hl_ctx_init(hdev, hdev->kernel_ctx, true);
 	if (rc) {
 		dev_err(hdev->dev, "failed to initialize kernel context\n");
-		goto free_ctx;
+		kfree(hdev->kernel_ctx);
+		goto mmu_fini;
 	}
 
 	rc = hl_cb_pool_init(hdev);
@@ -1053,8 +1054,6 @@ release_ctx:
 	if (hl_ctx_put(hdev->kernel_ctx) != 1)
 		dev_err(hdev->dev,
 			"kernel ctx is still alive on initialization failure\n");
-free_ctx:
-	kfree(hdev->kernel_ctx);
 mmu_fini:
 	hl_mmu_fini(hdev);
 eq_fini: