arm64: Blacklist non-kprobe-able symbol

commit 44b53f67c99d0fc53af3066a05d9e7ca5080a850 upstream.

Add all function symbols which are called from do_debug_exception under
NOKPROBE_SYMBOL, as they can not kprobed.

Signed-off-by: Pratyush Anand <panand@redhat.com>
Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: David A. Long <dave.long@linaro.org>

diff --git a/arch/arm64/kernel/arm64ksyms.c b/arch/arm64/kernel/arm64ksyms.c
index 3b6d8cc9dfe00ce14b764a3102ad0cd73f546c82..fbec403a2466dd4e705f1e3251355997ae37119b 100644 (file)
--- a/arch/arm64/kernel/arm64ksyms.c
+++ b/arch/arm64/kernel/arm64ksyms.c
@@ -26,6 +26,7 @@
 #include <linux/syscalls.h>
 #include <linux/uaccess.h>
 #include <linux/io.h>
+#include <linux/kprobes.h>
 
 #include <asm/checksum.h>
 
@@ -67,4 +68,5 @@ EXPORT_SYMBOL(test_and_change_bit);
 
 #ifdef CONFIG_FUNCTION_TRACER
 EXPORT_SYMBOL(_mcount);
+NOKPROBE_SYMBOL(_mcount);
 #endif

diff --git a/arch/arm64/kernel/debug-monitors.c b/arch/arm64/kernel/debug-monitors.c
index 17a4d3798cc458ab891a181e5b2fcb3a91233f24..6de6d9f43b959fd1cbb45a16bdc33bba524fccd6 100644 (file)
--- a/arch/arm64/kernel/debug-monitors.c
+++ b/arch/arm64/kernel/debug-monitors.c
@@ -49,6 +49,7 @@ static void mdscr_write(u32 mdscr)
        asm volatile("msr mdscr_el1, %0" :: "r" (mdscr));
        local_dbg_restore(flags);
 }
+NOKPROBE_SYMBOL(mdscr_write);
 
 static u32 mdscr_read(void)
 {
@@ -56,6 +57,7 @@ static u32 mdscr_read(void)
        asm volatile("mrs %0, mdscr_el1" : "=r" (mdscr));
        return mdscr;
 }
+NOKPROBE_SYMBOL(mdscr_read);
 
 /*
  * Allow root to disable self-hosted debug from userspace.
@@ -104,6 +106,7 @@ void enable_debug_monitors(enum dbg_active_el el)
                mdscr_write(mdscr);
        }
 }
+NOKPROBE_SYMBOL(enable_debug_monitors);
 
 void disable_debug_monitors(enum dbg_active_el el)
 {
@@ -124,6 +127,7 @@ void disable_debug_monitors(enum dbg_active_el el)
                mdscr_write(mdscr);
        }
 }
+NOKPROBE_SYMBOL(disable_debug_monitors);
 
 /*
  * OS lock clearing.
@@ -174,6 +178,7 @@ static void set_regs_spsr_ss(struct pt_regs *regs)
        spsr |= DBG_SPSR_SS;
        regs->pstate = spsr;
 }
+NOKPROBE_SYMBOL(set_regs_spsr_ss);
 
 static void clear_regs_spsr_ss(struct pt_regs *regs)
 {
@@ -183,6 +188,7 @@ static void clear_regs_spsr_ss(struct pt_regs *regs)
        spsr &= ~DBG_SPSR_SS;
        regs->pstate = spsr;
 }
+NOKPROBE_SYMBOL(clear_regs_spsr_ss);
 
 /* EL1 Single Step Handler hooks */
 static LIST_HEAD(step_hook);
@@ -226,6 +232,7 @@ static int call_step_hook(struct pt_regs *regs, unsigned int esr)
 
        return retval;
 }
+NOKPROBE_SYMBOL(call_step_hook);
 
 static int single_step_handler(unsigned long addr, unsigned int esr,
                               struct pt_regs *regs)
@@ -271,6 +278,7 @@ static int single_step_handler(unsigned long addr, unsigned int esr,
 
        return 0;
 }
+NOKPROBE_SYMBOL(single_step_handler);
 
 /*
  * Breakpoint handler is re-entrant as another breakpoint can
@@ -308,6 +316,7 @@ static int call_break_hook(struct pt_regs *regs, unsigned int esr)
 
        return fn ? fn(regs, esr) : DBG_HOOK_ERROR;
 }
+NOKPROBE_SYMBOL(call_break_hook);
 
 static int brk_handler(unsigned long addr, unsigned int esr,
                       struct pt_regs *regs)
@@ -337,6 +346,7 @@ static int brk_handler(unsigned long addr, unsigned int esr,
 
        return 0;
 }
+NOKPROBE_SYMBOL(brk_handler);
 
 int aarch32_break_handler(struct pt_regs *regs)
 {
@@ -381,6 +391,7 @@ int aarch32_break_handler(struct pt_regs *regs)
        force_sig_info(SIGTRAP, &info, current);
        return 0;
 }
+NOKPROBE_SYMBOL(aarch32_break_handler);
 
 static int __init debug_traps_init(void)
 {
@@ -402,6 +413,7 @@ void user_rewind_single_step(struct task_struct *task)
        if (test_ti_thread_flag(task_thread_info(task), TIF_SINGLESTEP))
                set_regs_spsr_ss(task_pt_regs(task));
 }
+NOKPROBE_SYMBOL(user_rewind_single_step);
 
 void user_fastforward_single_step(struct task_struct *task)
 {
@@ -417,6 +429,7 @@ void kernel_enable_single_step(struct pt_regs *regs)
        mdscr_write(mdscr_read() | DBG_MDSCR_SS);
        enable_debug_monitors(DBG_ACTIVE_EL1);
 }
+NOKPROBE_SYMBOL(kernel_enable_single_step);
 
 void kernel_disable_single_step(void)
 {
@@ -424,12 +437,14 @@ void kernel_disable_single_step(void)
        mdscr_write(mdscr_read() & ~DBG_MDSCR_SS);
        disable_debug_monitors(DBG_ACTIVE_EL1);
 }
+NOKPROBE_SYMBOL(kernel_disable_single_step);
 
 int kernel_active_single_step(void)
 {
        WARN_ON(!irqs_disabled());
        return mdscr_read() & DBG_MDSCR_SS;
 }
+NOKPROBE_SYMBOL(kernel_active_single_step);
 
 /* ptrace API */
 void user_enable_single_step(struct task_struct *task)
@@ -439,8 +454,10 @@ void user_enable_single_step(struct task_struct *task)
        if (!test_and_set_ti_thread_flag(ti, TIF_SINGLESTEP))
                set_regs_spsr_ss(task_pt_regs(task));
 }
+NOKPROBE_SYMBOL(user_enable_single_step);
 
 void user_disable_single_step(struct task_struct *task)
 {
        clear_ti_thread_flag(task_thread_info(task), TIF_SINGLESTEP);
 }
+NOKPROBE_SYMBOL(user_disable_single_step);

diff --git a/arch/arm64/kernel/hw_breakpoint.c b/arch/arm64/kernel/hw_breakpoint.c
index b45c95d34b8323e74992e0a4a56e6da0e1257c60..367a954f9937979c574a805bab2e3cbad706d202 100644 (file)
--- a/arch/arm64/kernel/hw_breakpoint.c
+++ b/arch/arm64/kernel/hw_breakpoint.c
@@ -24,6 +24,7 @@
 #include <linux/cpu_pm.h>
 #include <linux/errno.h>
 #include <linux/hw_breakpoint.h>
+#include <linux/kprobes.h>
 #include <linux/perf_event.h>
 #include <linux/ptrace.h>
 #include <linux/smp.h>
@@ -127,6 +128,7 @@ static u64 read_wb_reg(int reg, int n)
 
        return val;
 }
+NOKPROBE_SYMBOL(read_wb_reg);
 
 static void write_wb_reg(int reg, int n, u64 val)
 {
@@ -140,6 +142,7 @@ static void write_wb_reg(int reg, int n, u64 val)
        }
        isb();
 }
+NOKPROBE_SYMBOL(write_wb_reg);
 
 /*
  * Convert a breakpoint privilege level to the corresponding exception
@@ -157,6 +160,7 @@ static enum dbg_active_el debug_exception_level(int privilege)
                return -EINVAL;
        }
 }
+NOKPROBE_SYMBOL(debug_exception_level);
 
 enum hw_breakpoint_ops {
        HW_BREAKPOINT_INSTALL,
@@ -575,6 +579,7 @@ static void toggle_bp_registers(int reg, enum dbg_active_el el, int enable)
                write_wb_reg(reg, i, ctrl);
        }
 }
+NOKPROBE_SYMBOL(toggle_bp_registers);
 
 /*
  * Debug exception handlers.
@@ -654,6 +659,7 @@ unlock:
 
        return 0;
 }
+NOKPROBE_SYMBOL(breakpoint_handler);
 
 static int watchpoint_handler(unsigned long addr, unsigned int esr,
                              struct pt_regs *regs)
@@ -756,6 +762,7 @@ unlock:
 
        return 0;
 }
+NOKPROBE_SYMBOL(watchpoint_handler);
 
 /*
  * Handle single-step exception.
@@ -813,6 +820,7 @@ int reinstall_suspended_bps(struct pt_regs *regs)
 
        return !handled_exception;
 }
+NOKPROBE_SYMBOL(reinstall_suspended_bps);
 
 /*
  * Context-switcher for restoring suspended breakpoints.

diff --git a/arch/arm64/kernel/kgdb.c b/arch/arm64/kernel/kgdb.c
index bcac81e600b9af09341cffdd80d83880626f77b2..814d0c51b2f91b2e2e696ad81ec8066f3ed0d5be 100644 (file)
--- a/arch/arm64/kernel/kgdb.c
+++ b/arch/arm64/kernel/kgdb.c
@@ -22,6 +22,7 @@
 #include <linux/irq.h>
 #include <linux/kdebug.h>
 #include <linux/kgdb.h>
+#include <linux/kprobes.h>
 #include <asm/traps.h>
 
 struct dbg_reg_def_t dbg_reg_def[DBG_MAX_REG_NUM] = {
@@ -218,6 +219,7 @@ static int kgdb_brk_fn(struct pt_regs *regs, unsigned int esr)
        kgdb_handle_exception(1, SIGTRAP, 0, regs);
        return 0;
 }
+NOKPROBE_SYMBOL(kgdb_brk_fn)
 
 static int kgdb_compiled_brk_fn(struct pt_regs *regs, unsigned int esr)
 {
@@ -226,12 +228,14 @@ static int kgdb_compiled_brk_fn(struct pt_regs *regs, unsigned int esr)
 
        return 0;
 }
+NOKPROBE_SYMBOL(kgdb_compiled_brk_fn);
 
 static int kgdb_step_brk_fn(struct pt_regs *regs, unsigned int esr)
 {
        kgdb_handle_exception(1, SIGTRAP, 0, regs);
        return 0;
 }
+NOKPROBE_SYMBOL(kgdb_step_brk_fn);
 
 static struct break_hook kgdb_brkpt_hook = {
        .esr_mask       = 0xffffffff,