mm/memory.c: check return value of ioremap_prot

[ Upstream commit 24eee1e ] ioremap_prot() can return NULL which could lead to an oops. Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: chen jie <[email protected]> Reviewed-by: Andrew Morton <[email protected]> Cc: Li Zefan <[email protected]> Cc: chenjie <[email protected]> Cc: Yang Shi <[email protected]> Cc: Alexey Dobriyan <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]> Signed-off-by: Sasha Levin <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]>
nemunaire · Sep 5, 2018 · 4c41a07 · 4c41a07
1 parent f3ab050
commit 4c41a07
Showing 1 changed file with 3 additions and 0 deletions.
diff --git a/mm/memory.c b/mm/memory.c
@@ -3522,6 +3522,9 @@ int generic_access_phys(struct vm_area_struct *vma, unsigned long addr,
 		return -EINVAL;
 
 	maddr = ioremap_prot(phys_addr, PAGE_ALIGN(len + offset), prot);
+	if (!maddr)
+		return -ENOMEM;
+
 	if (write)
 		memcpy_toio(maddr + offset, buf, len);
 	else