Variable IoBuffer.InputLength is chosen from userspace, and can therefore be less than the intended size. In this case,the memory from the kmalloc call is eventually cast to a PBULKWRM_BUFFER. If the IoBuffer.InputLength does not meet the minimum size of PBULKWRM_BUFFER, then we will get a kernel Oops. To resolve this issue, this patch verifies IoBuffer.InputLength meets the minimum size before invoking the kmalloc call. Signed-off-by: Kevin McKinney <klmckinney1@xxxxxxxxx> --- drivers/staging/bcm/Bcmchar.c | 4 +++- 1 files changed, 3 insertions(+), 1 deletions(-) diff --git a/drivers/staging/bcm/Bcmchar.c b/drivers/staging/bcm/Bcmchar.c index fa4a854..179707b 100644 --- a/drivers/staging/bcm/Bcmchar.c +++ b/drivers/staging/bcm/Bcmchar.c @@ -1137,7 +1137,9 @@ cntrlEnd: if (copy_from_user(&IoBuffer, argp, sizeof(IOCTL_BUFFER))) return -EFAULT; - /* FIXME: restrict length */ + if (IoBuffer.InputLength < sizeof(ULONG) * 2) + return -EINVAL; + pvBuffer = kmalloc(IoBuffer.InputLength, GFP_KERNEL); if (!pvBuffer) return -ENOMEM; -- 1.7.4.1 _______________________________________________ devel mailing list devel@xxxxxxxxxxxxxxxxxxxxxx http://driverdev.linuxdriverproject.org/mailman/listinfo/devel
