Improve fb_mmap bounds checks in gbefb, smscufx, udlfb and vfb drivers to prevent possible uint overflows.
Signed-off-by: Tomi Valkeinen <[email protected]> Cc: Steve Glendinning <[email protected]> Cc: Bernie Thompson <[email protected]> --- drivers/video/gbefb.c | 4 +++- drivers/video/smscufx.c | 6 +++++- drivers/video/udlfb.c | 6 +++++- drivers/video/vfb.c | 7 +++++-- 4 files changed, 18 insertions(+), 5 deletions(-) diff --git a/drivers/video/gbefb.c b/drivers/video/gbefb.c index bda5e39..ceab370 100644 --- a/drivers/video/gbefb.c +++ b/drivers/video/gbefb.c @@ -1016,7 +1016,9 @@ static int gbefb_mmap(struct fb_info *info, /* check range */ if (vma->vm_pgoff > (~0UL >> PAGE_SHIFT)) return -EINVAL; - if (offset + size > gbe_mem_size) + if (size > gbe_mem_size) + return -EINVAL; + if (offset > gbe_mem_size - size) return -EINVAL; /* remap using the fastest write-through mode on architecture */ diff --git a/drivers/video/smscufx.c b/drivers/video/smscufx.c index 97bd662..b2b33fc 100644 --- a/drivers/video/smscufx.c +++ b/drivers/video/smscufx.c @@ -782,7 +782,11 @@ static int ufx_ops_mmap(struct fb_info *info, struct vm_area_struct *vma) unsigned long offset = vma->vm_pgoff << PAGE_SHIFT; unsigned long page, pos; - if (offset + size > info->fix.smem_len) + if (vma->vm_pgoff > (~0UL >> PAGE_SHIFT)) + return -EINVAL; + if (size > info->fix.smem_len) + return -EINVAL; + if (offset > info->fix.smem_len - size) return -EINVAL; pos = (unsigned long)info->fix.smem_start + offset; diff --git a/drivers/video/udlfb.c b/drivers/video/udlfb.c index 86d449e..ec03e72 100644 --- a/drivers/video/udlfb.c +++ b/drivers/video/udlfb.c @@ -324,7 +324,11 @@ static int dlfb_ops_mmap(struct fb_info *info, struct vm_area_struct *vma) unsigned long offset = vma->vm_pgoff << PAGE_SHIFT; unsigned long page, pos; - if (offset + size > info->fix.smem_len) + if (vma->vm_pgoff > (~0UL >> PAGE_SHIFT)) + return -EINVAL; + if (size > info->fix.smem_len) + return -EINVAL; + if (offset > info->fix.smem_len - size) return -EINVAL; pos = (unsigned long)info->fix.smem_start + offset; diff --git a/drivers/video/vfb.c b/drivers/video/vfb.c index 8bc1f93..ee5985e 100644 --- a/drivers/video/vfb.c +++ b/drivers/video/vfb.c @@ -420,9 +420,12 @@ static int vfb_mmap(struct fb_info *info, unsigned long offset = vma->vm_pgoff << PAGE_SHIFT; unsigned long page, pos; - if (offset + size > info->fix.smem_len) { + if (vma->vm_pgoff > (~0UL >> PAGE_SHIFT)) + return -EINVAL; + if (size > info->fix.smem_len) + return -EINVAL; + if (offset > info->fix.smem_len - size) return -EINVAL; - } pos = (unsigned long)info->fix.smem_start + offset; -- 1.7.10.4 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
