4.4-stable review patch. If anyone has any objections, please let me know. ------------------ From: "jie@chenjie6@xxxxxxxxx" <jie@chenjie6@xxxxxxxxx> [ Upstream commit 24eee1e4c47977bdfb71d6f15f6011e7b6188d04 ] ioremap_prot() can return NULL which could lead to an oops. Link: http://lkml.kernel.org/r/1533195441-58594-1-git-send-email-chenjie6@xxxxxxxxxx Signed-off-by: chen jie <chenjie6@xxxxxxxxxx> Reviewed-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> Cc: Li Zefan <lizefan@xxxxxxxxxx> Cc: chenjie <chenjie6@xxxxxxxxxx> Cc: Yang Shi <shy828301@xxxxxxxxx> Cc: Alexey Dobriyan <adobriyan@xxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> Signed-off-by: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx> Signed-off-by: Sasha Levin <alexander.levin@xxxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- mm/memory.c | 3 +++ 1 file changed, 3 insertions(+) --- a/mm/memory.c +++ b/mm/memory.c @@ -3701,6 +3701,9 @@ int generic_access_phys(struct vm_area_s 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
