4.14-stable review patch. If anyone has any objections, please let me know.
------------------ From: Thomas Gleixner <[email protected]> commit 7f414195b0c3612acd12b4611a5fe75995cf10c7 upstream. Andy prefers to be paranoid about the pagetable free in the error path of write_ldt(). Make it conditional and warn whenever the installment of a secondary LDT fails. Requested-by: Andy Lutomirski <[email protected]> Signed-off-by: Thomas Gleixner <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]> --- arch/x86/kernel/ldt.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) --- a/arch/x86/kernel/ldt.c +++ b/arch/x86/kernel/ldt.c @@ -426,7 +426,8 @@ static int write_ldt(void __user *ptr, u * already installed then the PTE page is already * populated. Mop up a half populated page table. */ - free_ldt_pgtables(mm); + if (!WARN_ON_ONCE(old_ldt)) + free_ldt_pgtables(mm); free_ldt_struct(new_ldt); goto out_unlock; }
