[PATCH 6.19 574/781] gpib: Fix memory leak in ni_usb_init()

Greg Kroah-Hartman
2026-02-25T01:37:46Z

From: Zilin Guan <zilin@seu.edu.cn>

[ Upstream commit b89921eed8cf2d97250bac4be38dbcfbf048b586 ]

In ni_usb_init(), if ni_usb_setup_init() fails, the function returns
-EFAULT without freeing the allocated writes buffer, leading to a
memory leak.

Additionally, ni_usb_setup_init() returns 0 on failure, which causes
ni_usb_init() to return -EFAULT, an inappropriate error code for this
situation.

Fix the leak by freeing writes in the error path. Modify
ni_usb_setup_init() to return -EINVAL on failure and propagate this
error code in ni_usb_init().

Fixes: 4e127de14fa7 ("staging: gpib: Add National Instruments USB GPIB driver")
Suggested-by: Greg KH <gregkh@linuxfoundation.org>
Suggested-by: Dave Penkler <dpenkler@gmail.com>
Co-developed-by: Jianhao Xu <jianhao.xu@seu.edu.cn>
Signed-off-by: Jianhao Xu <jianhao.xu@seu.edu.cn>
Signed-off-by: Zilin Guan <zilin@seu.edu.cn>
Link: https://patch.msgid.link/20251230034546.929452-1-zilin@seu.edu.cn
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/gpib/ni_usb/ni_usb_gpib.c | 12 +++++++-----
1 file changed, 7 insertions(+), 5 deletions(-)

diff --git a/drivers/gpib/ni_usb/ni_usb_gpib.c b/drivers/gpib/ni_usb/ni_usb_gpib.c
index fdcaa6c00bfea..b6fddb437f552 100644
--- a/drivers/gpib/ni_usb/ni_usb_gpib.c
+++ b/drivers/gpib/ni_usb/ni_usb_gpib.c
@@ -1780,7 +1780,7 @@ static int ni_usb_setup_init(struct gpib_board *board, struct ni_usb_register *w
i++;
if (i > NUM_INIT_WRITES) {
dev_err(&usb_dev->dev, "bug!, buffer overrun, i=%i\n", i);
- return 0;
+ return -EINVAL;
}
return i;
}
@@ -1799,10 +1799,12 @@ static int ni_usb_init(struct gpib_board *board)
return -ENOMEM;

writes_len = ni_usb_setup_init(board, writes);
- if (writes_len)
- retval = ni_usb_write_registers(ni_priv, writes, writes_len, &ibsta);
- else
- return -EFAULT;
+ if (writes_len < 0) {
+ kfree(writes);
+ return writes_len;
+ }
+
+ retval = ni_usb_write_registers(ni_priv, writes, writes_len, &ibsta);
kfree(writes);
if (retval) {
dev_err(&usb_dev->dev, "register write failed, retval=%i\n", retval);
--
2.51.0