[PATCH 5.15 171/917] USB: serial: keyspan: fix memleak on probe errors

Greg Kroah-Hartman
2021-11-16T01:03:58Z

From: Wang Hai <wanghai38@huawei.com>

commit 910c996335c37552ee30fcb837375b808bb4f33b upstream.

I got memory leak as follows when doing fault injection test:

unreferenced object 0xffff888258228440 (size 64):
comm "kworker/7:2", pid 2005, jiffies 4294989509 (age 824.540s)
hex dump (first 32 bytes):
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
backtrace:
[<ffffffff8167939c>] slab_post_alloc_hook+0x9c/0x490
[<ffffffff8167f627>] kmem_cache_alloc_trace+0x1f7/0x470
[<ffffffffa02ac0e4>] keyspan_port_probe+0xa4/0x5d0 [keyspan]
[<ffffffffa0294c07>] usb_serial_device_probe+0x97/0x1d0 [usbserial]
[<ffffffff82b50ca7>] really_probe+0x167/0x460
[<ffffffff82b51099>] __driver_probe_device+0xf9/0x180
[<ffffffff82b51173>] driver_probe_device+0x53/0x130
[<ffffffff82b516f5>] __device_attach_driver+0x105/0x130
[<ffffffff82b4cfe9>] bus_for_each_drv+0x129/0x190
[<ffffffff82b50a69>] __device_attach+0x1c9/0x270
[<ffffffff82b518d0>] device_initial_probe+0x20/0x30
[<ffffffff82b4f062>] bus_probe_device+0x142/0x160
[<ffffffff82b4a4e9>] device_add+0x829/0x1300
[<ffffffffa0295fda>] usb_serial_probe.cold+0xc9b/0x14ac [usbserial]
[<ffffffffa02266aa>] usb_probe_interface+0x1aa/0x3c0 [usbcore]
[<ffffffff82b50ca7>] really_probe+0x167/0x460

If keyspan_port_probe() fails to allocate memory for an out_buffer[i] or
in_buffer[i], the previously allocated memory for out_buffer or
in_buffer needs to be freed on the error handling path, otherwise a
memory leak will result.

Fixes: bad41a5bf177 ("USB: keyspan: fix port DMA-buffer allocations")
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Wang Hai <wanghai38@huawei.com>
Link: https://lore.kernel.org/r/20211015085543.1203011-1-wanghai38@huawei.com
Cc: stable@vger.kernel.org # 3.12
Signed-off-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
drivers/usb/serial/keyspan.c | 15 +++++++--------
1 file changed, 7 insertions(+), 8 deletions(-)

--- a/drivers/usb/serial/keyspan.c
+++ b/drivers/usb/serial/keyspan.c
@@ -2890,22 +2890,22 @@ static int keyspan_port_probe(struct usb
for (i = 0; i < ARRAY_SIZE(p_priv->in_buffer); ++i) {
p_priv->in_buffer[i] = kzalloc(IN_BUFLEN, GFP_KERNEL);
if (!p_priv->in_buffer[i])
- goto err_in_buffer;
+ goto err_free_in_buffer;
}

for (i = 0; i < ARRAY_SIZE(p_priv->out_buffer); ++i) {
p_priv->out_buffer[i] = kzalloc(OUT_BUFLEN, GFP_KERNEL);
if (!p_priv->out_buffer[i])
- goto err_out_buffer;
+ goto err_free_out_buffer;
}

p_priv->inack_buffer = kzalloc(INACK_BUFLEN, GFP_KERNEL);
if (!p_priv->inack_buffer)
- goto err_inack_buffer;
+ goto err_free_out_buffer;

p_priv->outcont_buffer = kzalloc(OUTCONT_BUFLEN, GFP_KERNEL);
if (!p_priv->outcont_buffer)
- goto err_outcont_buffer;
+ goto err_free_inack_buffer;

p_priv->device_details = d_details;

@@ -2951,15 +2951,14 @@ static int keyspan_port_probe(struct usb

return 0;

-err_outcont_buffer:
+err_free_inack_buffer:
kfree(p_priv->inack_buffer);
-err_inack_buffer:
+err_free_out_buffer:
for (i = 0; i < ARRAY_SIZE(p_priv->out_buffer); ++i)
kfree(p_priv->out_buffer[i]);
-err_out_buffer:
+err_free_in_buffer:
for (i = 0; i < ARRAY_SIZE(p_priv->in_buffer); ++i)
kfree(p_priv->in_buffer[i]);
-err_in_buffer:
kfree(p_priv);

return -ENOMEM;