Fix CVE-2017-1000364 for dragonboard-410c by backporting the patches from upstream...

[AGL/meta-agl.git] / meta-agl-bsp / meta-qcom / recipes-kernel / linux / files / 0002-Allow-stack-to-grow-up-to-address-space-limit.patch

diff --git a/meta-agl-bsp/meta-qcom/recipes-kernel/linux/files/0002-Allow-stack-to-grow-up-to-address-space-limit.patch b/meta-agl-bsp/meta-qcom/recipes-kernel/linux/files/0002-Allow-stack-to-grow-up-to-address-space-limit.patch
new file mode 100644 (file)
index 0000000..a729670
--- /dev/null
+++ b/meta-agl-bsp/meta-qcom/recipes-kernel/linux/files/0002-Allow-stack-to-grow-up-to-address-space-limit.patch
@@ -0,0 +1,51 @@
+From cd9d55be3ed9827f11a4fe5aca2b8b2f848a7c28 Mon Sep 17 00:00:00 2001
+From: Helge Deller <deller@gmx.de>
+Date: Mon, 19 Jun 2017 17:34:05 +0200
+Subject: [PATCH 2/3] Allow stack to grow up to address space limit
+
+commit bd726c90b6b8ce87602208701b208a208e6d5600 upstream.
+
+Fix expand_upwards() on architectures with an upward-growing stack (parisc,
+metag and partly IA-64) to allow the stack to reliably grow exactly up to
+the address space limit given by TASK_SIZE.
+
+Signed-off-by: Helge Deller <deller@gmx.de>
+Acked-by: Hugh Dickins <hughd@google.com>
+Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+---
+ mm/mmap.c | 13 ++++++++-----
+ 1 file changed, 8 insertions(+), 5 deletions(-)
+
+diff --git a/mm/mmap.c b/mm/mmap.c
+index 26542b3..d71a61e 100644
+--- a/mm/mmap.c
++++ b/mm/mmap.c
+@@ -2224,16 +2224,19 @@ int expand_upwards(struct vm_area_struct *vma, unsigned long address)
+       if (!(vma->vm_flags & VM_GROWSUP))
+               return -EFAULT;
+ 
+-      /* Guard against wrapping around to address 0. */
++      /* Guard against exceeding limits of the address space. */
+       address &= PAGE_MASK;
+-      address += PAGE_SIZE;
+-      if (!address)
++      if (address >= TASK_SIZE)
+               return -ENOMEM;
++      address += PAGE_SIZE;
+ 
+       /* Enforce stack_guard_gap */
+       gap_addr = address + stack_guard_gap;
+-      if (gap_addr < address)
+-              return -ENOMEM;
++
++      /* Guard against overflow */
++      if (gap_addr < address || gap_addr > TASK_SIZE)
++              gap_addr = TASK_SIZE;
++
+       next = vma->vm_next;
+       if (next && next->vm_start < gap_addr) {
+               if (!(next->vm_flags & VM_GROWSUP))
+-- 
+2.1.4
+