[PATCH 3.8 80/91] Fix a few incorrectly checked [io_]remap_pfn_range() calls

From: Kamal Mostafa
Date: Thu Nov 07 2013 - 21:17:54 EST


3.8.13.13 -stable review patch. If anyone has any objections, please let me know.

------------------

From: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx>

commit 7314e613d5ff9f0934f7a0f74ed7973b903315d1 upstream.

Nico Golde reports a few straggling uses of [io_]remap_pfn_range() that
really should use the vm_iomap_memory() helper. This trivially converts
two of them to the helper, and comments about why the third one really
needs to continue to use remap_pfn_range(), and adds the missing size
check.

Reported-by: Nico Golde <nico@xxxxxxxxx>
Signed-off-by: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxxx
[ kamal: backport to 3.8 (no uio_physical_vm_ops; context) ]
Signed-off-by: Kamal Mostafa <kamal@xxxxxxxxxxxxx>
---
drivers/uio/uio.c | 16 +++++++++++++++-
drivers/video/au1100fb.c | 26 +-------------------------
drivers/video/au1200fb.c | 25 +------------------------
3 files changed, 17 insertions(+), 50 deletions(-)

diff --git a/drivers/uio/uio.c b/drivers/uio/uio.c
index 5110f36..96f1359 100644
--- a/drivers/uio/uio.c
+++ b/drivers/uio/uio.c
@@ -650,14 +650,28 @@ static int uio_mmap_physical(struct vm_area_struct *vma)
{
struct uio_device *idev = vma->vm_private_data;
int mi = uio_find_mem_index(vma);
+ struct uio_mem *mem;
if (mi < 0)
return -EINVAL;
+ mem = idev->info->mem + mi;
+
+ if (vma->vm_end - vma->vm_start > mem->size)
+ return -EINVAL;

vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);

+ /*
+ * We cannot use the vm_iomap_memory() helper here,
+ * because vma->vm_pgoff is the map index we looked
+ * up above in uio_find_mem_index(), rather than an
+ * actual page offset into the mmap.
+ *
+ * So we just do the physical mmap without a page
+ * offset.
+ */
return remap_pfn_range(vma,
vma->vm_start,
- idev->info->mem[mi].addr >> PAGE_SHIFT,
+ mem->addr >> PAGE_SHIFT,
vma->vm_end - vma->vm_start,
vma->vm_page_prot);
}
diff --git a/drivers/video/au1100fb.c b/drivers/video/au1100fb.c
index ddabaa8..f8d8b97 100644
--- a/drivers/video/au1100fb.c
+++ b/drivers/video/au1100fb.c
@@ -375,39 +375,15 @@ void au1100fb_fb_rotate(struct fb_info *fbi, int angle)
int au1100fb_fb_mmap(struct fb_info *fbi, struct vm_area_struct *vma)
{
struct au1100fb_device *fbdev;
- unsigned int len;
- unsigned long start=0, off;

fbdev = to_au1100fb_device(fbi);

- if (vma->vm_pgoff > (~0UL >> PAGE_SHIFT)) {
- return -EINVAL;
- }
-
- start = fbdev->fb_phys & PAGE_MASK;
- len = PAGE_ALIGN((start & ~PAGE_MASK) + fbdev->fb_len);
-
- off = vma->vm_pgoff << PAGE_SHIFT;
-
- if ((vma->vm_end - vma->vm_start + off) > len) {
- return -EINVAL;
- }
-
- off += start;
- vma->vm_pgoff = off >> PAGE_SHIFT;
-
vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);
pgprot_val(vma->vm_page_prot) |= (6 << 9); //CCA=6

vma->vm_flags |= VM_IO;

- if (io_remap_pfn_range(vma, vma->vm_start, off >> PAGE_SHIFT,
- vma->vm_end - vma->vm_start,
- vma->vm_page_prot)) {
- return -EAGAIN;
- }
-
- return 0;
+ return vm_iomap_memory(vma, fbdev->fb_phys, fbdev->fb_len);
}

static struct fb_ops au1100fb_ops =
diff --git a/drivers/video/au1200fb.c b/drivers/video/au1200fb.c
index 1b59054..8f08ae7 100644
--- a/drivers/video/au1200fb.c
+++ b/drivers/video/au1200fb.c
@@ -1233,38 +1233,15 @@ static int au1200fb_fb_blank(int blank_mode, struct fb_info *fbi)
* method mainly to allow the use of the TLB streaming flag (CCA=6)
*/
static int au1200fb_fb_mmap(struct fb_info *info, struct vm_area_struct *vma)
-
{
- unsigned int len;
- unsigned long start=0, off;
struct au1200fb_device *fbdev = info->par;

- if (vma->vm_pgoff > (~0UL >> PAGE_SHIFT)) {
- return -EINVAL;
- }
-
- start = fbdev->fb_phys & PAGE_MASK;
- len = PAGE_ALIGN((start & ~PAGE_MASK) + fbdev->fb_len);
-
- off = vma->vm_pgoff << PAGE_SHIFT;
-
- if ((vma->vm_end - vma->vm_start + off) > len) {
- return -EINVAL;
- }
-
- off += start;
- vma->vm_pgoff = off >> PAGE_SHIFT;
-
vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);
pgprot_val(vma->vm_page_prot) |= _CACHE_MASK; /* CCA=7 */

vma->vm_flags |= VM_IO;

- return io_remap_pfn_range(vma, vma->vm_start, off >> PAGE_SHIFT,
- vma->vm_end - vma->vm_start,
- vma->vm_page_prot);
-
- return 0;
+ return vm_iomap_memory(vma, fbdev->fb_phys, fbdev->fb_len);
}

static void set_global(u_int cmd, struct au1200_lcd_global_regs_t *pdata)
--
1.8.1.2

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