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| author | Oliver Neukum <oneukum@suse.com> | 2024-10-07 12:39:47 +0300 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2024-10-17 16:24:33 +0300 |
| commit | 936564b4dafa98117b1f1d16f23f9cd7e397a5d7 (patch) | |
| tree | 1ea5c917683097469fb050fc997a8079e1e905c9 | |
| parent | 1fa959e74e507e303fbfa3f6fecbc8b543790de9 (diff) | |
| download | linux-936564b4dafa98117b1f1d16f23f9cd7e397a5d7.tar.xz | |
Revert "usb: yurex: Replace snprintf() with the safer scnprintf() variant"
commit 71c717cd8a2e180126932cc6851ff21c1d04d69a upstream.
This reverts commit 86b20af11e84c26ae3fde4dcc4f490948e3f8035.
This patch leads to passing 0 to simple_read_from_buffer()
as a fifth argument, turning the read method into a nop.
The change is fundamentally flawed, as it breaks the driver.
Signed-off-by: Oliver Neukum <oneukum@suse.com>
Cc: stable <stable@kernel.org>
Link: https://lore.kernel.org/r/20241007094004.242122-1-oneukum@suse.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -rw-r--r-- | drivers/usb/misc/yurex.c | 19 |
1 files changed, 8 insertions, 11 deletions
diff --git a/drivers/usb/misc/yurex.c b/drivers/usb/misc/yurex.c index 6adaaf66c14d..c313cd41f7a5 100644 --- a/drivers/usb/misc/yurex.c +++ b/drivers/usb/misc/yurex.c @@ -34,8 +34,6 @@ #define YUREX_BUF_SIZE 8 #define YUREX_WRITE_TIMEOUT (HZ*2) -#define MAX_S64_STRLEN 20 /* {-}922337203685477580{7,8} */ - /* table of devices that work with this driver */ static struct usb_device_id yurex_table[] = { { USB_DEVICE(YUREX_VENDOR_ID, YUREX_PRODUCT_ID) }, @@ -403,7 +401,8 @@ static ssize_t yurex_read(struct file *file, char __user *buffer, size_t count, { struct usb_yurex *dev; int len = 0; - char in_buffer[MAX_S64_STRLEN]; + char in_buffer[20]; + unsigned long flags; dev = file->private_data; @@ -413,16 +412,14 @@ static ssize_t yurex_read(struct file *file, char __user *buffer, size_t count, return -ENODEV; } - if (WARN_ON_ONCE(dev->bbu > S64_MAX || dev->bbu < S64_MIN)) { - mutex_unlock(&dev->io_mutex); - return -EIO; - } - - spin_lock_irq(&dev->lock); - scnprintf(in_buffer, MAX_S64_STRLEN, "%lld\n", dev->bbu); - spin_unlock_irq(&dev->lock); + spin_lock_irqsave(&dev->lock, flags); + len = snprintf(in_buffer, 20, "%lld\n", dev->bbu); + spin_unlock_irqrestore(&dev->lock, flags); mutex_unlock(&dev->io_mutex); + if (WARN_ON_ONCE(len >= sizeof(in_buffer))) + return -EIO; + return simple_read_from_buffer(buffer, count, ppos, in_buffer, len); } |