Commit 508c5849 authored Aug 01, 2019 by Tomer Tayar Committed by Oded Gabbay Aug 12, 2019

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>

parent d45331b0

drivers/misc/habanalabs/device.c

+2 −3

Original line number	Diff line number	Diff line
		@@ -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:

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