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authorTakashi Iwai <tiwai@suse.de>2020-08-03 15:41:43 +0300
committerTakashi Iwai <tiwai@suse.de>2020-08-03 15:41:43 +0300
commit103f528d3bc35d2b6e726a3fffd879e492d191c2 (patch)
tree2829604c2386f96e228fac7841e49906f698dfff /arch/x86/entry
parent07c9983b567d0ef33aefc063299de95a987e12a8 (diff)
parent84569f329f7fcb40b7b1860f273b2909dabf2a2b (diff)
downloadlinux-103f528d3bc35d2b6e726a3fffd879e492d191c2.tar.xz
Merge tag 'asoc-v5.9' of https://git.kernel.org/pub/scm/linux/kernel/git/broonie/sound into for-linus
ASoC: Updates for v5.9 The biggest changes here one again come from Mormioto-san who has continued his dilligent work cleaning up long standing issues in the APIs, it's particularly nice to see the transition from digital_mute() to mute_stream() finally completed. There's also been a lot of work on the x86 code again, this time a big focus has been on cleaning up some issues identified by various static tests, and on the Freescale systems. Otherwise the biggest thing has been a lot of driver additions: - Convert users of digital_mute() to mute_stream(). - Simplify I/O helper functions. - Add a helper for getting the RTD from a substream. - Many, many fixes and cleanups to the x86 code. - New drivers for Freescale MQS and i.MX6sx, Intel KeemBay I2S, Maxim MAX98360A and MAX98373 Soundwire, several Mediatek boards, nVidia Tegra 186 and 210, RealTek RL6231, Samsung Midas and Aries boards (some of the first phones I worked on!) and TI J721e EVM.
Diffstat (limited to 'arch/x86/entry')
-rw-r--r--arch/x86/entry/Makefile14
-rw-r--r--arch/x86/entry/common.c51
-rw-r--r--arch/x86/entry/entry_32.S5
-rw-r--r--arch/x86/entry/entry_64_compat.S31
4 files changed, 76 insertions, 25 deletions
diff --git a/arch/x86/entry/Makefile b/arch/x86/entry/Makefile
index b7a5790d8d63..08bf95dbc911 100644
--- a/arch/x86/entry/Makefile
+++ b/arch/x86/entry/Makefile
@@ -7,12 +7,20 @@ KASAN_SANITIZE := n
UBSAN_SANITIZE := n
KCOV_INSTRUMENT := n
-CFLAGS_REMOVE_common.o = $(CC_FLAGS_FTRACE) -fstack-protector -fstack-protector-strong
-CFLAGS_REMOVE_syscall_32.o = $(CC_FLAGS_FTRACE) -fstack-protector -fstack-protector-strong
-CFLAGS_REMOVE_syscall_64.o = $(CC_FLAGS_FTRACE) -fstack-protector -fstack-protector-strong
+CFLAGS_REMOVE_common.o = $(CC_FLAGS_FTRACE)
+CFLAGS_REMOVE_syscall_64.o = $(CC_FLAGS_FTRACE)
+CFLAGS_REMOVE_syscall_32.o = $(CC_FLAGS_FTRACE)
+CFLAGS_REMOVE_syscall_x32.o = $(CC_FLAGS_FTRACE)
+
+CFLAGS_common.o += -fno-stack-protector
+CFLAGS_syscall_64.o += -fno-stack-protector
+CFLAGS_syscall_32.o += -fno-stack-protector
+CFLAGS_syscall_x32.o += -fno-stack-protector
CFLAGS_syscall_64.o += $(call cc-option,-Wno-override-init,)
CFLAGS_syscall_32.o += $(call cc-option,-Wno-override-init,)
+CFLAGS_syscall_x32.o += $(call cc-option,-Wno-override-init,)
+
obj-y := entry_$(BITS).o thunk_$(BITS).o syscall_$(BITS).o
obj-y += common.o
diff --git a/arch/x86/entry/common.c b/arch/x86/entry/common.c
index bd3f14175193..f09288431f28 100644
--- a/arch/x86/entry/common.c
+++ b/arch/x86/entry/common.c
@@ -45,6 +45,32 @@
#define CREATE_TRACE_POINTS
#include <trace/events/syscalls.h>
+/* Check that the stack and regs on entry from user mode are sane. */
+static noinstr void check_user_regs(struct pt_regs *regs)
+{
+ if (IS_ENABLED(CONFIG_DEBUG_ENTRY)) {
+ /*
+ * Make sure that the entry code gave us a sensible EFLAGS
+ * register. Native because we want to check the actual CPU
+ * state, not the interrupt state as imagined by Xen.
+ */
+ unsigned long flags = native_save_fl();
+ WARN_ON_ONCE(flags & (X86_EFLAGS_AC | X86_EFLAGS_DF |
+ X86_EFLAGS_NT));
+
+ /* We think we came from user mode. Make sure pt_regs agrees. */
+ WARN_ON_ONCE(!user_mode(regs));
+
+ /*
+ * All entries from user mode (except #DF) should be on the
+ * normal thread stack and should have user pt_regs in the
+ * correct location.
+ */
+ WARN_ON_ONCE(!on_thread_stack());
+ WARN_ON_ONCE(regs != task_pt_regs(current));
+ }
+}
+
#ifdef CONFIG_CONTEXT_TRACKING
/**
* enter_from_user_mode - Establish state when coming from user mode
@@ -127,9 +153,6 @@ static long syscall_trace_enter(struct pt_regs *regs)
unsigned long ret = 0;
u32 work;
- if (IS_ENABLED(CONFIG_DEBUG_ENTRY))
- BUG_ON(regs != task_pt_regs(current));
-
work = READ_ONCE(ti->flags);
if (work & (_TIF_SYSCALL_TRACE | _TIF_SYSCALL_EMU)) {
@@ -271,7 +294,7 @@ static void __prepare_exit_to_usermode(struct pt_regs *regs)
#endif
}
-__visible noinstr void prepare_exit_to_usermode(struct pt_regs *regs)
+static noinstr void prepare_exit_to_usermode(struct pt_regs *regs)
{
instrumentation_begin();
__prepare_exit_to_usermode(regs);
@@ -346,6 +369,8 @@ __visible noinstr void do_syscall_64(unsigned long nr, struct pt_regs *regs)
{
struct thread_info *ti;
+ check_user_regs(regs);
+
enter_from_user_mode();
instrumentation_begin();
@@ -409,6 +434,8 @@ static void do_syscall_32_irqs_on(struct pt_regs *regs)
/* Handles int $0x80 */
__visible noinstr void do_int80_syscall_32(struct pt_regs *regs)
{
+ check_user_regs(regs);
+
enter_from_user_mode();
instrumentation_begin();
@@ -460,6 +487,8 @@ __visible noinstr long do_fast_syscall_32(struct pt_regs *regs)
vdso_image_32.sym_int80_landing_pad;
bool success;
+ check_user_regs(regs);
+
/*
* SYSENTER loses EIP, and even SYSCALL32 needs us to skip forward
* so that 'regs->ip -= 2' lands back on an int $0x80 instruction.
@@ -510,6 +539,18 @@ __visible noinstr long do_fast_syscall_32(struct pt_regs *regs)
(regs->flags & (X86_EFLAGS_RF | X86_EFLAGS_TF | X86_EFLAGS_VM)) == 0;
#endif
}
+
+/* Returns 0 to return using IRET or 1 to return using SYSEXIT/SYSRETL. */
+__visible noinstr long do_SYSENTER_32(struct pt_regs *regs)
+{
+ /* SYSENTER loses RSP, but the vDSO saved it in RBP. */
+ regs->sp = regs->bp;
+
+ /* SYSENTER clobbers EFLAGS.IF. Assume it was set in usermode. */
+ regs->flags |= X86_EFLAGS_IF;
+
+ return do_fast_syscall_32(regs);
+}
#endif
SYSCALL_DEFINE0(ni_syscall)
@@ -553,6 +594,7 @@ SYSCALL_DEFINE0(ni_syscall)
bool noinstr idtentry_enter_cond_rcu(struct pt_regs *regs)
{
if (user_mode(regs)) {
+ check_user_regs(regs);
enter_from_user_mode();
return false;
}
@@ -686,6 +728,7 @@ void noinstr idtentry_exit_cond_rcu(struct pt_regs *regs, bool rcu_exit)
*/
void noinstr idtentry_enter_user(struct pt_regs *regs)
{
+ check_user_regs(regs);
enter_from_user_mode();
}
diff --git a/arch/x86/entry/entry_32.S b/arch/x86/entry/entry_32.S
index 024d7d276cd4..2d0bd5d5f032 100644
--- a/arch/x86/entry/entry_32.S
+++ b/arch/x86/entry/entry_32.S
@@ -933,9 +933,8 @@ SYM_FUNC_START(entry_SYSENTER_32)
.Lsysenter_past_esp:
pushl $__USER_DS /* pt_regs->ss */
- pushl %ebp /* pt_regs->sp (stashed in bp) */
+ pushl $0 /* pt_regs->sp (placeholder) */
pushfl /* pt_regs->flags (except IF = 0) */
- orl $X86_EFLAGS_IF, (%esp) /* Fix IF */
pushl $__USER_CS /* pt_regs->cs */
pushl $0 /* pt_regs->ip = 0 (placeholder) */
pushl %eax /* pt_regs->orig_ax */
@@ -965,7 +964,7 @@ SYM_FUNC_START(entry_SYSENTER_32)
.Lsysenter_flags_fixed:
movl %esp, %eax
- call do_fast_syscall_32
+ call do_SYSENTER_32
/* XEN PV guests always use IRET path */
ALTERNATIVE "testl %eax, %eax; jz .Lsyscall_32_done", \
"jmp .Lsyscall_32_done", X86_FEATURE_XENPV
diff --git a/arch/x86/entry/entry_64_compat.S b/arch/x86/entry/entry_64_compat.S
index 0f974ae01e62..541fdaf64045 100644
--- a/arch/x86/entry/entry_64_compat.S
+++ b/arch/x86/entry/entry_64_compat.S
@@ -57,29 +57,30 @@ SYM_CODE_START(entry_SYSENTER_compat)
movq PER_CPU_VAR(cpu_current_top_of_stack), %rsp
- /*
- * User tracing code (ptrace or signal handlers) might assume that
- * the saved RAX contains a 32-bit number when we're invoking a 32-bit
- * syscall. Just in case the high bits are nonzero, zero-extend
- * the syscall number. (This could almost certainly be deleted
- * with no ill effects.)
- */
- movl %eax, %eax
-
/* Construct struct pt_regs on stack */
pushq $__USER32_DS /* pt_regs->ss */
- pushq %rbp /* pt_regs->sp (stashed in bp) */
+ pushq $0 /* pt_regs->sp = 0 (placeholder) */
/*
* Push flags. This is nasty. First, interrupts are currently
- * off, but we need pt_regs->flags to have IF set. Second, even
- * if TF was set when SYSENTER started, it's clear by now. We fix
- * that later using TIF_SINGLESTEP.
+ * off, but we need pt_regs->flags to have IF set. Second, if TS
+ * was set in usermode, it's still set, and we're singlestepping
+ * through this code. do_SYSENTER_32() will fix up IF.
*/
pushfq /* pt_regs->flags (except IF = 0) */
- orl $X86_EFLAGS_IF, (%rsp) /* Fix saved flags */
pushq $__USER32_CS /* pt_regs->cs */
pushq $0 /* pt_regs->ip = 0 (placeholder) */
+SYM_INNER_LABEL(entry_SYSENTER_compat_after_hwframe, SYM_L_GLOBAL)
+
+ /*
+ * User tracing code (ptrace or signal handlers) might assume that
+ * the saved RAX contains a 32-bit number when we're invoking a 32-bit
+ * syscall. Just in case the high bits are nonzero, zero-extend
+ * the syscall number. (This could almost certainly be deleted
+ * with no ill effects.)
+ */
+ movl %eax, %eax
+
pushq %rax /* pt_regs->orig_ax */
pushq %rdi /* pt_regs->di */
pushq %rsi /* pt_regs->si */
@@ -135,7 +136,7 @@ SYM_CODE_START(entry_SYSENTER_compat)
.Lsysenter_flags_fixed:
movq %rsp, %rdi
- call do_fast_syscall_32
+ call do_SYSENTER_32
/* XEN PV guests always use IRET path */
ALTERNATIVE "testl %eax, %eax; jz swapgs_restore_regs_and_return_to_usermode", \
"jmp swapgs_restore_regs_and_return_to_usermode", X86_FEATURE_XENPV