Implement specific usage of verify_pre_usermode_state for user-mode returns for arm64. Signed-off-by: Thomas Garnier <thgarnie@xxxxxxxxxx> --- Based on next-20170404 --- arch/arm64/Kconfig | 1 + arch/arm64/kernel/entry.S | 15 +++++++++++++++ 2 files changed, 16 insertions(+) diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig index f2b0b528037d..0e86d87259f4 100644 --- a/arch/arm64/Kconfig +++ b/arch/arm64/Kconfig @@ -24,6 +24,7 @@ config ARM64 select ARCH_WANT_COMPAT_IPC_PARSE_VERSION select ARCH_WANT_FRAME_POINTERS select ARCH_HAS_UBSAN_SANITIZE_ALL + select ARCH_NO_SYSCALL_VERIFY_PRE_USERMODE_STATE select ARM_AMBA select ARM_ARCH_TIMER select ARM_GIC diff --git a/arch/arm64/kernel/entry.S b/arch/arm64/kernel/entry.S index 43512d4d7df2..6d598e7051c3 100644 --- a/arch/arm64/kernel/entry.S +++ b/arch/arm64/kernel/entry.S @@ -744,6 +744,10 @@ ENDPROC(cpu_switch_to) ret_fast_syscall: disable_irq // disable interrupts str x0, [sp, #S_X0] // returned x0 + ldr x2, [tsk, #TSK_TI_ADDR_LIMIT] // check addr limit change + mov x1, #TASK_SIZE_64 + cmp x2, x1 + b.ne addr_limit_fail ldr x1, [tsk, #TSK_TI_FLAGS] // re-check for syscall tracing and x2, x1, #_TIF_SYSCALL_WORK cbnz x2, ret_fast_syscall_trace @@ -771,6 +775,11 @@ work_pending: */ ret_to_user: disable_irq // disable interrupts + ldr x2, [tsk, #TSK_TI_ADDR_LIMIT] // check addr limit change + mov x1, #TASK_SIZE_64 + cmp x2, x1 + b.ne addr_limit_fail + ldr x1, [tsk, #TSK_TI_FLAGS] and x2, x1, #_TIF_WORK_MASK cbnz x2, work_pending @@ -779,6 +788,12 @@ finish_ret_to_user: kernel_exit 0 ENDPROC(ret_to_user) +addr_limit_fail: + stp x0, lr, [sp,#-16]! + bl asm_verify_pre_usermode_state + ldp x0, lr, [sp],#16 + ret lr + /* * This is how we return from a fork. */ -- 2.12.2.715.g7642488e1d-goog -- To unsubscribe from this list: send the line "unsubscribe linux-s390" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
