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Diffstat (limited to 'arch/arm/kernel/ptrace.c')
-rw-r--r--arch/arm/kernel/ptrace.c139
1 files changed, 76 insertions, 63 deletions
diff --git a/arch/arm/kernel/ptrace.c b/arch/arm/kernel/ptrace.c
index 97260060bf2..0c27ed6f3f2 100644
--- a/arch/arm/kernel/ptrace.c
+++ b/arch/arm/kernel/ptrace.c
@@ -12,6 +12,7 @@
#include <linux/kernel.h>
#include <linux/sched.h>
#include <linux/mm.h>
+#include <linux/elf.h>
#include <linux/smp.h>
#include <linux/ptrace.h>
#include <linux/user.h>
@@ -22,11 +23,16 @@
#include <linux/perf_event.h>
#include <linux/hw_breakpoint.h>
#include <linux/regset.h>
+#include <linux/audit.h>
+#include <linux/tracehook.h>
+#include <linux/unistd.h>
#include <asm/pgtable.h>
-#include <asm/system.h>
#include <asm/traps.h>
+#define CREATE_TRACE_POINTS
+#include <trace/events/syscalls.h>
+
#define REG_PC 15
#define REG_PSR 16
/*
@@ -228,34 +234,12 @@ static struct undef_hook thumb_break_hook = {
.fn = break_trap,
};
-static int thumb2_break_trap(struct pt_regs *regs, unsigned int instr)
-{
- unsigned int instr2;
- void __user *pc;
-
- /* Check the second half of the instruction. */
- pc = (void __user *)(instruction_pointer(regs) + 2);
-
- if (processor_mode(regs) == SVC_MODE) {
- instr2 = *(u16 *) pc;
- } else {
- get_user(instr2, (u16 __user *)pc);
- }
-
- if (instr2 == 0xa000) {
- ptrace_break(current, regs);
- return 0;
- } else {
- return 1;
- }
-}
-
static struct undef_hook thumb2_break_hook = {
- .instr_mask = 0xffff,
- .instr_val = 0xf7f0,
+ .instr_mask = 0xffffffff,
+ .instr_val = 0xf7f0a000,
.cpsr_mask = PSR_T_BIT,
.cpsr_val = PSR_T_BIT,
- .fn = thumb2_break_trap,
+ .fn = break_trap,
};
static int __init ptrace_break_init(void)
@@ -277,7 +261,7 @@ static int ptrace_read_user(struct task_struct *tsk, unsigned long off,
{
unsigned long tmp;
- if (off & 3 || off >= sizeof(struct user))
+ if (off & 3)
return -EIO;
tmp = 0;
@@ -289,6 +273,8 @@ static int ptrace_read_user(struct task_struct *tsk, unsigned long off,
tmp = tsk->mm->end_code;
else if (off < sizeof(struct pt_regs))
tmp = get_user_reg(tsk, off >> 2);
+ else if (off >= sizeof(struct user))
+ return -EIO;
return put_user(tmp, ret);
}
@@ -396,7 +382,7 @@ static long ptrace_hbp_idx_to_num(int idx)
/*
* Handle hitting a HW-breakpoint.
*/
-static void ptrace_hbptriggered(struct perf_event *bp, int unused,
+static void ptrace_hbptriggered(struct perf_event *bp,
struct perf_sample_data *data,
struct pt_regs *regs)
{
@@ -479,7 +465,8 @@ static struct perf_event *ptrace_hbp_create(struct task_struct *tsk, int type)
attr.bp_type = type;
attr.disabled = 1;
- return register_user_hw_breakpoint(&attr, ptrace_hbptriggered, tsk);
+ return register_user_hw_breakpoint(&attr, ptrace_hbptriggered, NULL,
+ tsk);
}
static int ptrace_gethbpregs(struct task_struct *tsk, long num,
@@ -719,10 +706,13 @@ static int vfp_set(struct task_struct *target,
{
int ret;
struct thread_info *thread = task_thread_info(target);
- struct vfp_hard_struct new_vfp = thread->vfpstate.hard;
+ struct vfp_hard_struct new_vfp;
const size_t user_fpregs_offset = offsetof(struct user_vfp, fpregs);
const size_t user_fpscr_offset = offsetof(struct user_vfp, fpscr);
+ vfp_sync_hwstate(thread);
+ new_vfp = thread->vfpstate.hard;
+
ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
&new_vfp.fpregs,
user_fpregs_offset,
@@ -743,9 +733,8 @@ static int vfp_set(struct task_struct *target,
if (ret)
return ret;
- vfp_sync_hwstate(thread);
- thread->vfpstate.hard = new_vfp;
vfp_flush_hwstate(thread);
+ thread->vfpstate.hard = new_vfp;
return 0;
}
@@ -860,7 +849,7 @@ long arch_ptrace(struct task_struct *child, long request,
#endif
case PTRACE_GET_THREAD_AREA:
- ret = put_user(task_thread_info(child)->tp_value,
+ ret = put_user(task_thread_info(child)->tp_value[0],
datap);
break;
@@ -897,20 +886,12 @@ long arch_ptrace(struct task_struct *child, long request,
#ifdef CONFIG_HAVE_HW_BREAKPOINT
case PTRACE_GETHBPREGS:
- if (ptrace_get_breakpoints(child) < 0)
- return -ESRCH;
-
ret = ptrace_gethbpregs(child, addr,
(unsigned long __user *)data);
- ptrace_put_breakpoints(child);
break;
case PTRACE_SETHBPREGS:
- if (ptrace_get_breakpoints(child) < 0)
- return -ESRCH;
-
ret = ptrace_sethbpregs(child, addr,
(unsigned long __user *)data);
- ptrace_put_breakpoints(child);
break;
#endif
@@ -922,38 +903,70 @@ long arch_ptrace(struct task_struct *child, long request,
return ret;
}
-asmlinkage int syscall_trace(int why, struct pt_regs *regs, int scno)
+enum ptrace_syscall_dir {
+ PTRACE_SYSCALL_ENTER = 0,
+ PTRACE_SYSCALL_EXIT,
+};
+
+static void tracehook_report_syscall(struct pt_regs *regs,
+ enum ptrace_syscall_dir dir)
{
unsigned long ip;
- if (!test_thread_flag(TIF_SYSCALL_TRACE))
- return scno;
- if (!(current->ptrace & PT_PTRACED))
- return scno;
-
/*
- * Save IP. IP is used to denote syscall entry/exit:
- * IP = 0 -> entry, = 1 -> exit
+ * IP is used to denote syscall entry/exit:
+ * IP = 0 -> entry, =1 -> exit
*/
ip = regs->ARM_ip;
- regs->ARM_ip = why;
+ regs->ARM_ip = dir;
+
+ if (dir == PTRACE_SYSCALL_EXIT)
+ tracehook_report_syscall_exit(regs, 0);
+ else if (tracehook_report_syscall_entry(regs))
+ current_thread_info()->syscall = -1;
+ regs->ARM_ip = ip;
+}
+
+asmlinkage int syscall_trace_enter(struct pt_regs *regs, int scno)
+{
current_thread_info()->syscall = scno;
- /* the 0x80 provides a way for the tracing parent to distinguish
- between a syscall stop and SIGTRAP delivery */
- ptrace_notify(SIGTRAP | ((current->ptrace & PT_TRACESYSGOOD)
- ? 0x80 : 0));
+ /* Do the secure computing check first; failures should be fast. */
+ if (secure_computing(scno) == -1)
+ return -1;
+
+ if (test_thread_flag(TIF_SYSCALL_TRACE))
+ tracehook_report_syscall(regs, PTRACE_SYSCALL_ENTER);
+
+ scno = current_thread_info()->syscall;
+
+ if (test_thread_flag(TIF_SYSCALL_TRACEPOINT))
+ trace_sys_enter(regs, scno);
+
+ audit_syscall_entry(AUDIT_ARCH_ARM, scno, regs->ARM_r0, regs->ARM_r1,
+ regs->ARM_r2, regs->ARM_r3);
+
+ return scno;
+}
+
+asmlinkage void syscall_trace_exit(struct pt_regs *regs)
+{
/*
- * this isn't the same as continuing with a signal, but it will do
- * for normal use. strace only continues with a signal if the
- * stopping signal is not SIGTRAP. -brl
+ * Audit the syscall before anything else, as a debugger may
+ * come in and change the current registers.
*/
- if (current->exit_code) {
- send_sig(current->exit_code, current, 1);
- current->exit_code = 0;
- }
- regs->ARM_ip = ip;
+ audit_syscall_exit(regs);
+
+ /*
+ * Note that we haven't updated the ->syscall field for the
+ * current thread. This isn't a problem because it will have
+ * been set on syscall entry and there hasn't been an opportunity
+ * for a PTRACE_SET_SYSCALL since then.
+ */
+ if (test_thread_flag(TIF_SYSCALL_TRACEPOINT))
+ trace_sys_exit(regs, regs_return_value(regs));
- return current_thread_info()->syscall;
+ if (test_thread_flag(TIF_SYSCALL_TRACE))
+ tracehook_report_syscall(regs, PTRACE_SYSCALL_EXIT);
}
generated by cgit v1.2.3-70-g09d2 (git 2.46.0) at 2025-12-07 16:39:37 +0000