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From:   Kunwu Chan <chentao@kylinos.cn>
To:     fbarrat@linux.ibm.com, ajd@linux.ibm.com, arnd@arndb.de,
        gregkh@linuxfoundation.org, mpe@ellerman.id.au,
        mrochs@linux.vnet.ibm.com
Cc:     kunwu.chan@hotmail.com, linuxppc-dev@lists.ozlabs.org,
        linux-kernel@vger.kernel.org, Kunwu Chan <chentao@kylinos.cn>
Subject: [PATCH] cxl: Fix null pointer dereference in cxl_get_fd
Date:   Mon,  4 Dec 2023 10:07:45 +0800
Message-Id: <20231204020745.2445944-1-chentao@kylinos.cn>
MIME-Version: 1.0
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Precedence: bulk

kasprintf() returns a pointer to dynamically allocated memory
which can be NULL upon failure.

Fixes: bdecf76e319a ("cxl: Fix coredump generation when cxl_get_fd() is used")
Signed-off-by: Kunwu Chan <chentao@kylinos.cn>
---
 drivers/misc/cxl/api.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/drivers/misc/cxl/api.c b/drivers/misc/cxl/api.c
index d85c56530863..bfd7ccd4d7e1 100644
--- a/drivers/misc/cxl/api.c
+++ b/drivers/misc/cxl/api.c
@@ -419,6 +419,10 @@ struct file *cxl_get_fd(struct cxl_context *ctx, struct file_operations *fops,
 		fops = (struct file_operations *)&afu_fops;
 
 	name = kasprintf(GFP_KERNEL, "cxl:%d", ctx->pe);
+	if (!name) {
+		put_unused_fd(fdtmp);
+		return ERR_PTR(-ENOMEM);
+	}
 	file = cxl_getfile(name, fops, ctx, flags);
 	kfree(name);
 	if (IS_ERR(file))
-- 
2.34.1