diff --git a/arch/arm64/include/asm/brk-imm.h b/arch/arm64/include/asm/brk-imm.h index 2945fe6cd863c2..fec9e138464101 100644 --- a/arch/arm64/include/asm/brk-imm.h +++ b/arch/arm64/include/asm/brk-imm.h @@ -23,5 +23,6 @@ #define KGDB_COMPILED_DBG_BRK_IMM 0x401 #define BUG_BRK_IMM 0x800 #define KASAN_BRK_IMM 0x900 +#define KASAN_BRK_MASK 0x0ff #endif diff --git a/arch/arm64/include/asm/debug-monitors.h b/arch/arm64/include/asm/debug-monitors.h index a44cf522542961..7d37cfa5cc1665 100644 --- a/arch/arm64/include/asm/debug-monitors.h +++ b/arch/arm64/include/asm/debug-monitors.h @@ -94,18 +94,24 @@ struct step_hook { int (*fn)(struct pt_regs *regs, unsigned int esr); }; -void register_step_hook(struct step_hook *hook); -void unregister_step_hook(struct step_hook *hook); +void register_user_step_hook(struct step_hook *hook); +void unregister_user_step_hook(struct step_hook *hook); + +void register_kernel_step_hook(struct step_hook *hook); +void unregister_kernel_step_hook(struct step_hook *hook); struct break_hook { struct list_head node; - u32 esr_val; - u32 esr_mask; int (*fn)(struct pt_regs *regs, unsigned int esr); + u16 imm; + u16 mask; /* These bits are ignored when comparing with imm */ }; -void register_break_hook(struct break_hook *hook); -void unregister_break_hook(struct break_hook *hook); +void register_user_break_hook(struct break_hook *hook); +void unregister_user_break_hook(struct break_hook *hook); + +void register_kernel_break_hook(struct break_hook *hook); +void unregister_kernel_break_hook(struct break_hook *hook); u8 debug_monitors_arch(void); diff --git a/arch/arm64/kernel/debug-monitors.c b/arch/arm64/kernel/debug-monitors.c index 744229d10ca8d2..9b3fd7fa5b4363 100644 --- a/arch/arm64/kernel/debug-monitors.c +++ b/arch/arm64/kernel/debug-monitors.c @@ -163,25 +163,46 @@ static void clear_regs_spsr_ss(struct pt_regs *regs) } NOKPROBE_SYMBOL(clear_regs_spsr_ss); -/* EL1 Single Step Handler hooks */ -static LIST_HEAD(step_hook); -static DEFINE_SPINLOCK(step_hook_lock); +static DEFINE_SPINLOCK(debug_hook_lock); +static LIST_HEAD(user_step_hook); +static LIST_HEAD(kernel_step_hook); -void register_step_hook(struct step_hook *hook) +static void register_debug_hook(struct list_head *node, struct list_head *list) { - spin_lock(&step_hook_lock); - list_add_rcu(&hook->node, &step_hook); - spin_unlock(&step_hook_lock); + spin_lock(&debug_hook_lock); + list_add_rcu(node, list); + spin_unlock(&debug_hook_lock); + } -void unregister_step_hook(struct step_hook *hook) +static void unregister_debug_hook(struct list_head *node) { - spin_lock(&step_hook_lock); - list_del_rcu(&hook->node); - spin_unlock(&step_hook_lock); + spin_lock(&debug_hook_lock); + list_del_rcu(node); + spin_unlock(&debug_hook_lock); synchronize_rcu(); } +void register_user_step_hook(struct step_hook *hook) +{ + register_debug_hook(&hook->node, &user_step_hook); +} + +void unregister_user_step_hook(struct step_hook *hook) +{ + unregister_debug_hook(&hook->node); +} + +void register_kernel_step_hook(struct step_hook *hook) +{ + register_debug_hook(&hook->node, &kernel_step_hook); +} + +void unregister_kernel_step_hook(struct step_hook *hook) +{ + unregister_debug_hook(&hook->node); +} + /* * Call registered single step handlers * There is no Syndrome info to check for determining the handler. @@ -191,11 +212,14 @@ void unregister_step_hook(struct step_hook *hook) static int call_step_hook(struct pt_regs *regs, unsigned int esr) { struct step_hook *hook; + struct list_head *list; int retval = DBG_HOOK_ERROR; + list = user_mode(regs) ? &user_step_hook : &kernel_step_hook; + rcu_read_lock(); - list_for_each_entry_rcu(hook, &step_hook, node) { + list_for_each_entry_rcu(hook, list, node) { retval = hook->fn(regs, esr); if (retval == DBG_HOOK_HANDLED) break; @@ -264,33 +288,44 @@ static int single_step_handler(unsigned long unused, unsigned int esr, } NOKPROBE_SYMBOL(single_step_handler); -static LIST_HEAD(break_hook); -static DEFINE_SPINLOCK(break_hook_lock); +static LIST_HEAD(user_break_hook); +static LIST_HEAD(kernel_break_hook); -void register_break_hook(struct break_hook *hook) +void register_user_break_hook(struct break_hook *hook) { - spin_lock(&break_hook_lock); - list_add_rcu(&hook->node, &break_hook); - spin_unlock(&break_hook_lock); + register_debug_hook(&hook->node, &user_break_hook); } -void unregister_break_hook(struct break_hook *hook) +void unregister_user_break_hook(struct break_hook *hook) { - spin_lock(&break_hook_lock); - list_del_rcu(&hook->node); - spin_unlock(&break_hook_lock); - synchronize_rcu(); + unregister_debug_hook(&hook->node); +} + +void register_kernel_break_hook(struct break_hook *hook) +{ + register_debug_hook(&hook->node, &kernel_break_hook); +} + +void unregister_kernel_break_hook(struct break_hook *hook) +{ + unregister_debug_hook(&hook->node); } static int call_break_hook(struct pt_regs *regs, unsigned int esr) { struct break_hook *hook; + struct list_head *list; int (*fn)(struct pt_regs *regs, unsigned int esr) = NULL; + list = user_mode(regs) ? &user_break_hook : &kernel_break_hook; + rcu_read_lock(); - list_for_each_entry_rcu(hook, &break_hook, node) - if ((esr & hook->esr_mask) == hook->esr_val) + list_for_each_entry_rcu(hook, list, node) { + unsigned int comment = esr & BRK64_ESR_MASK; + + if ((comment & ~hook->mask) == hook->imm) fn = hook->fn; + } rcu_read_unlock(); return fn ? fn(regs, esr) : DBG_HOOK_ERROR; diff --git a/arch/arm64/kernel/kgdb.c b/arch/arm64/kernel/kgdb.c index 691854b77c7fe6..4c01f299aeb215 100644 --- a/arch/arm64/kernel/kgdb.c +++ b/arch/arm64/kernel/kgdb.c @@ -275,15 +275,13 @@ static int kgdb_step_brk_fn(struct pt_regs *regs, unsigned int esr) NOKPROBE_SYMBOL(kgdb_step_brk_fn); static struct break_hook kgdb_brkpt_hook = { - .esr_mask = 0xffffffff, - .esr_val = (u32)ESR_ELx_VAL_BRK64(KGDB_DYN_DBG_BRK_IMM), - .fn = kgdb_brk_fn + .fn = kgdb_brk_fn, + .imm = KGDB_DYN_DBG_BRK_IMM, }; static struct break_hook kgdb_compiled_brkpt_hook = { - .esr_mask = 0xffffffff, - .esr_val = (u32)ESR_ELx_VAL_BRK64(KGDB_COMPILED_DBG_BRK_IMM), - .fn = kgdb_compiled_brk_fn + .fn = kgdb_compiled_brk_fn, + .imm = KGDB_COMPILED_DBG_BRK_IMM, }; static struct step_hook kgdb_step_hook = { @@ -332,9 +330,9 @@ int kgdb_arch_init(void) if (ret != 0) return ret; - register_break_hook(&kgdb_brkpt_hook); - register_break_hook(&kgdb_compiled_brkpt_hook); - register_step_hook(&kgdb_step_hook); + register_kernel_break_hook(&kgdb_brkpt_hook); + register_kernel_break_hook(&kgdb_compiled_brkpt_hook); + register_kernel_step_hook(&kgdb_step_hook); return 0; } @@ -345,9 +343,9 @@ int kgdb_arch_init(void) */ void kgdb_arch_exit(void) { - unregister_break_hook(&kgdb_brkpt_hook); - unregister_break_hook(&kgdb_compiled_brkpt_hook); - unregister_step_hook(&kgdb_step_hook); + unregister_kernel_break_hook(&kgdb_brkpt_hook); + unregister_kernel_break_hook(&kgdb_compiled_brkpt_hook); + unregister_kernel_step_hook(&kgdb_step_hook); unregister_die_notifier(&kgdb_notifier); } diff --git a/arch/arm64/kernel/probes/uprobes.c b/arch/arm64/kernel/probes/uprobes.c index 636ca0119c0efa..7d6ea88796a6bf 100644 --- a/arch/arm64/kernel/probes/uprobes.c +++ b/arch/arm64/kernel/probes/uprobes.c @@ -195,8 +195,7 @@ static int uprobe_single_step_handler(struct pt_regs *regs, /* uprobe breakpoint handler hook */ static struct break_hook uprobes_break_hook = { - .esr_mask = BRK64_ESR_MASK, - .esr_val = BRK64_ESR_UPROBES, + .imm = BRK64_ESR_UPROBES, .fn = uprobe_breakpoint_handler, }; @@ -207,8 +206,8 @@ static struct step_hook uprobes_step_hook = { static int __init arch_init_uprobes(void) { - register_break_hook(&uprobes_break_hook); - register_step_hook(&uprobes_step_hook); + register_user_break_hook(&uprobes_break_hook); + register_user_step_hook(&uprobes_step_hook); return 0; } diff --git a/arch/arm64/kernel/traps.c b/arch/arm64/kernel/traps.c index 8ad119c3f665d4..85fdc3d7c5566c 100644 --- a/arch/arm64/kernel/traps.c +++ b/arch/arm64/kernel/traps.c @@ -969,9 +969,8 @@ static int bug_handler(struct pt_regs *regs, unsigned int esr) } static struct break_hook bug_break_hook = { - .esr_val = 0xf2000000 | BUG_BRK_IMM, - .esr_mask = 0xffffffff, .fn = bug_handler, + .imm = BUG_BRK_IMM, }; #ifdef CONFIG_KASAN_SW_TAGS @@ -1016,13 +1015,10 @@ static int kasan_handler(struct pt_regs *regs, unsigned int esr) return DBG_HOOK_HANDLED; } -#define KASAN_ESR_VAL (0xf2000000 | KASAN_BRK_IMM) -#define KASAN_ESR_MASK 0xffffff00 - static struct break_hook kasan_break_hook = { - .esr_val = KASAN_ESR_VAL, - .esr_mask = KASAN_ESR_MASK, - .fn = kasan_handler, + .fn = kasan_handler, + .imm = KASAN_BRK_IMM, + .mask = KASAN_BRK_MASK, }; #endif @@ -1034,7 +1030,9 @@ int __init early_brk64(unsigned long addr, unsigned int esr, struct pt_regs *regs) { #ifdef CONFIG_KASAN_SW_TAGS - if ((esr & KASAN_ESR_MASK) == KASAN_ESR_VAL) + unsigned int comment = esr & BRK64_ESR_MASK; + + if ((comment & ~KASAN_BRK_MASK) == KASAN_BRK_IMM) return kasan_handler(regs, esr) != DBG_HOOK_HANDLED; #endif return bug_handler(regs, esr) != DBG_HOOK_HANDLED; @@ -1043,8 +1041,8 @@ int __init early_brk64(unsigned long addr, unsigned int esr, /* This registration must happen early, before debug_traps_init(). */ void __init trap_init(void) { - register_break_hook(&bug_break_hook); + register_kernel_break_hook(&bug_break_hook); #ifdef CONFIG_KASAN_SW_TAGS - register_break_hook(&kasan_break_hook); + register_kernel_break_hook(&kasan_break_hook); #endif }