[PARISC] Handle wrapping in expand_upwards() (06b32f3a) · Commits · e / devices / android_kernel_oneplus_sm8150

Function expand_upwards() did not guarded against wrapping around to address 0. This fixes the adjtimex02 testcase from the Linux Test Project on a 32bit PARISC kernel. [expand_upwards is only used on parisc and ia64; it looks like it does the right thing on both. --kyle] Signed-off-by:

Helge Deller <deller@gmx.de> Cc: Tony Luck <tony.luck@intel.com> Signed-off-by:

Kyle McMartin <kyle@parisc-linux.org>

mm/mmap.c

+7 −2

Original line number	Diff line number	Diff line
		@@ -1536,9 +1536,14 @@ int expand_upwards(struct vm_area_struct *vma, unsigned long address)
		* vma->vm_start/vm_end cannot change under us because the caller
		* is required to hold the mmap_sem in read mode. We need the
		* anon_vma lock to serialize against concurrent expand_stacks.
		* Also guard against wrapping around to address 0.
		*/
		address += 4 + PAGE_SIZE - 1;
		address &= PAGE_MASK;
		if (address < PAGE_ALIGN(address+4))
		address = PAGE_ALIGN(address+4);
		else {
		anon_vma_unlock(vma);
		return -ENOMEM;
		}
		error = 0;

		/* Somebody else might have raced and expanded it already */