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-rw-r--r--patches/cve/CVE-2018-16276-USB-yurex-fix-out-of-bounds-uaccess-in-read-handler.patch75
1 files changed, 75 insertions, 0 deletions
diff --git a/patches/cve/CVE-2018-16276-USB-yurex-fix-out-of-bounds-uaccess-in-read-handler.patch b/patches/cve/CVE-2018-16276-USB-yurex-fix-out-of-bounds-uaccess-in-read-handler.patch
new file mode 100644
index 0000000..62b5e11
--- /dev/null
+++ b/patches/cve/CVE-2018-16276-USB-yurex-fix-out-of-bounds-uaccess-in-read-handler.patch
@@ -0,0 +1,75 @@
1From 90f2a76ccd37cce2530df49335bcea6cd0e23797 Mon Sep 17 00:00:00 2001
2From: Jann Horn <jannh@google.com>
3Date: Fri, 6 Jul 2018 17:12:56 +0200
4Subject: [PATCH] USB: yurex: fix out-of-bounds uaccess in read handler
5
6commit f1e255d60ae66a9f672ff9a207ee6cd8e33d2679 upstream.
7
8In general, accessing userspace memory beyond the length of the supplied
9buffer in VFS read/write handlers can lead to both kernel memory corruption
10(via kernel_read()/kernel_write(), which can e.g. be triggered via
11sys_splice()) and privilege escalation inside userspace.
12
13Fix it by using simple_read_from_buffer() instead of custom logic.
14
15CVE: CVE-2018-16276
16Upstream-Status: Backport [https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?h=linux-4.14.y&id=90f2a76ccd37cce2530df49335bcea6cd0e23797]
17
18Fixes: 6bc235a2e24a ("USB: add driver for Meywa-Denki & Kayac YUREX")
19Signed-off-by: Jann Horn <jannh@google.com>
20Cc: stable <stable@vger.kernel.org>
21Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
22Signed-off-by: Andreas Wellving <andreas.wellving@enea.com>
23---
24 drivers/usb/misc/yurex.c | 23 ++++++-----------------
25 1 file changed, 6 insertions(+), 17 deletions(-)
26
27diff --git a/drivers/usb/misc/yurex.c b/drivers/usb/misc/yurex.c
28index 58abdf28620a..47763311a42e 100644
29--- a/drivers/usb/misc/yurex.c
30+++ b/drivers/usb/misc/yurex.c
31@@ -400,8 +400,7 @@ static ssize_t yurex_read(struct file *file, char __user *buffer, size_t count,
32 loff_t *ppos)
33 {
34 struct usb_yurex *dev;
35- int retval = 0;
36- int bytes_read = 0;
37+ int len = 0;
38 char in_buffer[20];
39 unsigned long flags;
40
41@@ -409,26 +408,16 @@ static ssize_t yurex_read(struct file *file, char __user *buffer, size_t count,
42
43 mutex_lock(&dev->io_mutex);
44 if (!dev->interface) { /* already disconnected */
45- retval = -ENODEV;
46- goto exit;
47+ mutex_unlock(&dev->io_mutex);
48+ return -ENODEV;
49 }
50
51 spin_lock_irqsave(&dev->lock, flags);
52- bytes_read = snprintf(in_buffer, 20, "%lld\n", dev->bbu);
53+ len = snprintf(in_buffer, 20, "%lld\n", dev->bbu);
54 spin_unlock_irqrestore(&dev->lock, flags);
55-
56- if (*ppos < bytes_read) {
57- if (copy_to_user(buffer, in_buffer + *ppos, bytes_read - *ppos))
58- retval = -EFAULT;
59- else {
60- retval = bytes_read - *ppos;
61- *ppos += bytes_read;
62- }
63- }
64-
65-exit:
66 mutex_unlock(&dev->io_mutex);
67- return retval;
68+
69+ return simple_read_from_buffer(buffer, count, ppos, in_buffer, len);
70 }
71
72 static ssize_t yurex_write(struct file *file, const char __user *user_buffer,
73--
742.20.1
75