diff options
| author | Lee Jones <lee@kernel.org> | 2024-07-05 08:43:39 +0100 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2024-07-18 11:39:38 +0200 |
| commit | a444c3fc264119801575ab086e03fb4952f23fd0 (patch) | |
| tree | 1772b2d3db5b2edc0e3d62273e678f740e15f1fe | |
| parent | 1d1f3d602971bbb8de654e7bbe78bf6c2ebd06c1 (diff) | |
usb: gadget: configfs: Prevent OOB read/write in usb_string_copy()
commit 6d3c721e686ea6c59e18289b400cc95c76e927e0 upstream.
Userspace provided string 's' could trivially have the length zero. Left
unchecked this will firstly result in an OOB read in the form
`if (str[0 - 1] == '\n') followed closely by an OOB write in the form
`str[0 - 1] = '\0'`.
There is already a validating check to catch strings that are too long.
Let's supply an additional check for invalid strings that are too short.
Signed-off-by: Lee Jones <lee@kernel.org>
Cc: stable <stable@kernel.org>
Link: https://lore.kernel.org/r/20240705074339.633717-1-lee@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -rw-r--r-- | drivers/usb/gadget/configfs.c | 3 |
1 files changed, 3 insertions, 0 deletions
diff --git a/drivers/usb/gadget/configfs.c b/drivers/usb/gadget/configfs.c index 2350e97a1662..87657e0ca5fc 100644 --- a/drivers/usb/gadget/configfs.c +++ b/drivers/usb/gadget/configfs.c @@ -116,9 +116,12 @@ static int usb_string_copy(const char *s, char **s_copy) int ret; char *str; char *copy = *s_copy; + ret = strlen(s); if (ret > USB_MAX_STRING_LEN) return -EOVERFLOW; + if (ret < 1) + return -EINVAL; if (copy) { str = copy; |