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authorAndré Fabian Silva Delgado <emulatorman@parabola.nu>2016-08-05 02:19:08 -0300
committerAndré Fabian Silva Delgado <emulatorman@parabola.nu>2016-08-05 02:19:08 -0300
commit8dec7c70575785729a6a9e6719a955e9c545bcab (patch)
tree897b1b743b2ceb44ace956e8176b6a7e36751019 /arch/arm64
parent4411a04f871d94ae997fb7262a428fe2ee988eb3 (diff)
Linux-libre 4.6.5-gnupck-4.6.5-gnu
Diffstat (limited to 'arch/arm64')
-rw-r--r--arch/arm64/include/asm/ptrace.h2
-rw-r--r--arch/arm64/kernel/asm-offsets.c1
-rw-r--r--arch/arm64/kernel/entry.S19
-rw-r--r--arch/arm64/kernel/traps.c26
-rw-r--r--arch/arm64/mm/fault.c3
-rw-r--r--arch/arm64/mm/flush.c4
6 files changed, 35 insertions, 20 deletions
diff --git a/arch/arm64/include/asm/ptrace.h b/arch/arm64/include/asm/ptrace.h
index a307eb6e7..7f9475508 100644
--- a/arch/arm64/include/asm/ptrace.h
+++ b/arch/arm64/include/asm/ptrace.h
@@ -117,6 +117,8 @@ struct pt_regs {
};
u64 orig_x0;
u64 syscallno;
+ u64 orig_addr_limit;
+ u64 unused; // maintain 16 byte alignment
};
#define arch_has_single_step() (1)
diff --git a/arch/arm64/kernel/asm-offsets.c b/arch/arm64/kernel/asm-offsets.c
index 3ae6b310a..1abcd8829 100644
--- a/arch/arm64/kernel/asm-offsets.c
+++ b/arch/arm64/kernel/asm-offsets.c
@@ -59,6 +59,7 @@ int main(void)
DEFINE(S_PC, offsetof(struct pt_regs, pc));
DEFINE(S_ORIG_X0, offsetof(struct pt_regs, orig_x0));
DEFINE(S_SYSCALLNO, offsetof(struct pt_regs, syscallno));
+ DEFINE(S_ORIG_ADDR_LIMIT, offsetof(struct pt_regs, orig_addr_limit));
DEFINE(S_FRAME_SIZE, sizeof(struct pt_regs));
BLANK();
DEFINE(MM_CONTEXT_ID, offsetof(struct mm_struct, context.id.counter));
diff --git a/arch/arm64/kernel/entry.S b/arch/arm64/kernel/entry.S
index 12e8d2bcb..6c3b7345a 100644
--- a/arch/arm64/kernel/entry.S
+++ b/arch/arm64/kernel/entry.S
@@ -28,6 +28,7 @@
#include <asm/errno.h>
#include <asm/esr.h>
#include <asm/irq.h>
+#include <asm/memory.h>
#include <asm/thread_info.h>
#include <asm/unistd.h>
@@ -97,7 +98,14 @@
mov x29, xzr // fp pointed to user-space
.else
add x21, sp, #S_FRAME_SIZE
- .endif
+ get_thread_info tsk
+ /* Save the task's original addr_limit and set USER_DS (TASK_SIZE_64) */
+ ldr x20, [tsk, #TI_ADDR_LIMIT]
+ str x20, [sp, #S_ORIG_ADDR_LIMIT]
+ mov x20, #TASK_SIZE_64
+ str x20, [tsk, #TI_ADDR_LIMIT]
+ ALTERNATIVE(nop, SET_PSTATE_UAO(0), ARM64_HAS_UAO, CONFIG_ARM64_UAO)
+ .endif /* \el == 0 */
mrs x22, elr_el1
mrs x23, spsr_el1
stp lr, x21, [sp, #S_LR]
@@ -128,6 +136,14 @@
.endm
.macro kernel_exit, el
+ .if \el != 0
+ /* Restore the task's original addr_limit. */
+ ldr x20, [sp, #S_ORIG_ADDR_LIMIT]
+ str x20, [tsk, #TI_ADDR_LIMIT]
+
+ /* No need to restore UAO, it will be restored from SPSR_EL1 */
+ .endif
+
ldp x21, x22, [sp, #S_PC] // load ELR, SPSR
.if \el == 0
ct_user_enter
@@ -406,7 +422,6 @@ el1_irq:
bl trace_hardirqs_off
#endif
- get_thread_info tsk
irq_handler
#ifdef CONFIG_PREEMPT
diff --git a/arch/arm64/kernel/traps.c b/arch/arm64/kernel/traps.c
index c5392081b..58651a9df 100644
--- a/arch/arm64/kernel/traps.c
+++ b/arch/arm64/kernel/traps.c
@@ -64,8 +64,7 @@ static void dump_mem(const char *lvl, const char *str, unsigned long bottom,
/*
* We need to switch to kernel mode so that we can use __get_user
- * to safely read from kernel space. Note that we now dump the
- * code first, just in case the backtrace kills us.
+ * to safely read from kernel space.
*/
fs = get_fs();
set_fs(KERNEL_DS);
@@ -111,21 +110,12 @@ static void dump_backtrace_entry(unsigned long where)
print_ip_sym(where);
}
-static void dump_instr(const char *lvl, struct pt_regs *regs)
+static void __dump_instr(const char *lvl, struct pt_regs *regs)
{
unsigned long addr = instruction_pointer(regs);
- mm_segment_t fs;
char str[sizeof("00000000 ") * 5 + 2 + 1], *p = str;
int i;
- /*
- * We need to switch to kernel mode so that we can use __get_user
- * to safely read from kernel space. Note that we now dump the
- * code first, just in case the backtrace kills us.
- */
- fs = get_fs();
- set_fs(KERNEL_DS);
-
for (i = -4; i < 1; i++) {
unsigned int val, bad;
@@ -139,8 +129,18 @@ static void dump_instr(const char *lvl, struct pt_regs *regs)
}
}
printk("%sCode: %s\n", lvl, str);
+}
- set_fs(fs);
+static void dump_instr(const char *lvl, struct pt_regs *regs)
+{
+ if (!user_mode(regs)) {
+ mm_segment_t fs = get_fs();
+ set_fs(KERNEL_DS);
+ __dump_instr(lvl, regs);
+ set_fs(fs);
+ } else {
+ __dump_instr(lvl, regs);
+ }
}
static void dump_backtrace(struct pt_regs *regs, struct task_struct *tsk)
diff --git a/arch/arm64/mm/fault.c b/arch/arm64/mm/fault.c
index 10b79e9e8..e22849a90 100644
--- a/arch/arm64/mm/fault.c
+++ b/arch/arm64/mm/fault.c
@@ -284,7 +284,8 @@ static int __kprobes do_page_fault(unsigned long addr, unsigned int esr,
}
if (permission_fault(esr) && (addr < USER_DS)) {
- if (get_fs() == KERNEL_DS)
+ /* regs->orig_addr_limit may be 0 if we entered from EL0 */
+ if (regs->orig_addr_limit == KERNEL_DS)
die("Accessing user space memory with fs=KERNEL_DS", regs, esr);
if (!search_exception_tables(regs->pc))
diff --git a/arch/arm64/mm/flush.c b/arch/arm64/mm/flush.c
index dbd12ea8c..43a76b07e 100644
--- a/arch/arm64/mm/flush.c
+++ b/arch/arm64/mm/flush.c
@@ -71,10 +71,6 @@ void __sync_icache_dcache(pte_t pte, unsigned long addr)
{
struct page *page = pte_page(pte);
- /* no flushing needed for anonymous pages */
- if (!page_mapping(page))
- return;
-
if (!test_and_set_bit(PG_dcache_clean, &page->flags))
sync_icache_aliases(page_address(page),
PAGE_SIZE << compound_order(page));