5.4-stable review patch. If anyone has any objections, please let me know.
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From: Huai-Yuan Liu qq810974084@gmail.com
[ Upstream commit fbf740aeb86a4fe82ad158d26d711f2f3be79b3e ]
In register_device, the return value of ida_simple_get is unchecked, in witch ida_simple_get will use an invalid index value.
To address this issue, index should be checked after ida_simple_get. When the index value is abnormal, a warning message should be printed, the port should be dropped, and the value should be recorded.
Fixes: 9a69645dde11 ("ppdev: fix registering same device name") Signed-off-by: Huai-Yuan Liu qq810974084@gmail.com Link: https://lore.kernel.org/r/20240412083840.234085-1-qq810974084@gmail.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/char/ppdev.c | 15 +++++++++++---- 1 file changed, 11 insertions(+), 4 deletions(-)
diff --git a/drivers/char/ppdev.c b/drivers/char/ppdev.c index 5246e0faaf9ae..fb51430e1d5c6 100644 --- a/drivers/char/ppdev.c +++ b/drivers/char/ppdev.c @@ -296,28 +296,35 @@ static int register_device(int minor, struct pp_struct *pp) if (!port) { pr_warn("%s: no associated port!\n", name); rc = -ENXIO; - goto err; + goto err_free_name; }
index = ida_alloc(&ida_index, GFP_KERNEL); + if (index < 0) { + pr_warn("%s: failed to get index!\n", name); + rc = index; + goto err_put_port; + } + memset(&ppdev_cb, 0, sizeof(ppdev_cb)); ppdev_cb.irq_func = pp_irq; ppdev_cb.flags = (pp->flags & PP_EXCL) ? PARPORT_FLAG_EXCL : 0; ppdev_cb.private = pp; pdev = parport_register_dev_model(port, name, &ppdev_cb, index); - parport_put_port(port);
if (!pdev) { pr_warn("%s: failed to register device!\n", name); rc = -ENXIO; ida_free(&ida_index, index); - goto err; + goto err_put_port; }
pp->pdev = pdev; pp->index = index; dev_dbg(&pdev->dev, "registered pardevice\n"); -err: +err_put_port: + parport_put_port(port); +err_free_name: kfree(name); return rc; }