From 55a55fec5015b326235873b925a5882ac56ecaa2 Mon Sep 17 00:00:00 2001 From: Marco Elver Date: Mon, 9 Aug 2021 13:25:12 +0200 Subject: kcsan: Add ability to pass instruction pointer of access to reporting Add the ability to pass an explicitly set instruction pointer of access from check_access() all the way through to reporting. In preparation of using it in reporting. Signed-off-by: Marco Elver Signed-off-by: Paul E. McKenney --- kernel/kcsan/core.c | 55 ++++++++++++++++++++++++++++----------------------- kernel/kcsan/kcsan.h | 8 ++++---- kernel/kcsan/report.c | 20 ++++++++++--------- 3 files changed, 45 insertions(+), 38 deletions(-) (limited to 'kernel/kcsan') diff --git a/kernel/kcsan/core.c b/kernel/kcsan/core.c index 76e67d1e02d4..bffd1d95addb 100644 --- a/kernel/kcsan/core.c +++ b/kernel/kcsan/core.c @@ -350,6 +350,7 @@ void kcsan_restore_irqtrace(struct task_struct *task) static noinline void kcsan_found_watchpoint(const volatile void *ptr, size_t size, int type, + unsigned long ip, atomic_long_t *watchpoint, long encoded_watchpoint) { @@ -396,7 +397,7 @@ static noinline void kcsan_found_watchpoint(const volatile void *ptr, if (consumed) { kcsan_save_irqtrace(current); - kcsan_report_set_info(ptr, size, type, watchpoint - watchpoints); + kcsan_report_set_info(ptr, size, type, ip, watchpoint - watchpoints); kcsan_restore_irqtrace(current); } else { /* @@ -416,7 +417,7 @@ static noinline void kcsan_found_watchpoint(const volatile void *ptr, } static noinline void -kcsan_setup_watchpoint(const volatile void *ptr, size_t size, int type) +kcsan_setup_watchpoint(const volatile void *ptr, size_t size, int type, unsigned long ip) { const bool is_write = (type & KCSAN_ACCESS_WRITE) != 0; const bool is_assert = (type & KCSAN_ACCESS_ASSERT) != 0; @@ -568,8 +569,8 @@ kcsan_setup_watchpoint(const volatile void *ptr, size_t size, int type) if (is_assert && value_change == KCSAN_VALUE_CHANGE_TRUE) atomic_long_inc(&kcsan_counters[KCSAN_COUNTER_ASSERT_FAILURES]); - kcsan_report_known_origin(ptr, size, type, value_change, - watchpoint - watchpoints, + kcsan_report_known_origin(ptr, size, type, ip, + value_change, watchpoint - watchpoints, old, new, access_mask); } else if (value_change == KCSAN_VALUE_CHANGE_TRUE) { /* Inferring a race, since the value should not have changed. */ @@ -578,8 +579,10 @@ kcsan_setup_watchpoint(const volatile void *ptr, size_t size, int type) if (is_assert) atomic_long_inc(&kcsan_counters[KCSAN_COUNTER_ASSERT_FAILURES]); - if (IS_ENABLED(CONFIG_KCSAN_REPORT_RACE_UNKNOWN_ORIGIN) || is_assert) - kcsan_report_unknown_origin(ptr, size, type, old, new, access_mask); + if (IS_ENABLED(CONFIG_KCSAN_REPORT_RACE_UNKNOWN_ORIGIN) || is_assert) { + kcsan_report_unknown_origin(ptr, size, type, ip, + old, new, access_mask); + } } /* @@ -596,8 +599,8 @@ out: user_access_restore(ua_flags); } -static __always_inline void check_access(const volatile void *ptr, size_t size, - int type) +static __always_inline void +check_access(const volatile void *ptr, size_t size, int type, unsigned long ip) { const bool is_write = (type & KCSAN_ACCESS_WRITE) != 0; atomic_long_t *watchpoint; @@ -625,13 +628,12 @@ static __always_inline void check_access(const volatile void *ptr, size_t size, */ if (unlikely(watchpoint != NULL)) - kcsan_found_watchpoint(ptr, size, type, watchpoint, - encoded_watchpoint); + kcsan_found_watchpoint(ptr, size, type, ip, watchpoint, encoded_watchpoint); else { struct kcsan_ctx *ctx = get_ctx(); /* Call only once in fast-path. */ if (unlikely(should_watch(ptr, size, type, ctx))) - kcsan_setup_watchpoint(ptr, size, type); + kcsan_setup_watchpoint(ptr, size, type, ip); else if (unlikely(ctx->scoped_accesses.prev)) kcsan_check_scoped_accesses(); } @@ -757,7 +759,7 @@ kcsan_begin_scoped_access(const volatile void *ptr, size_t size, int type, { struct kcsan_ctx *ctx = get_ctx(); - __kcsan_check_access(ptr, size, type); + check_access(ptr, size, type, _RET_IP_); ctx->disable_count++; /* Disable KCSAN, in case list debugging is on. */ @@ -802,7 +804,7 @@ EXPORT_SYMBOL(kcsan_end_scoped_access); void __kcsan_check_access(const volatile void *ptr, size_t size, int type) { - check_access(ptr, size, type); + check_access(ptr, size, type, _RET_IP_); } EXPORT_SYMBOL(__kcsan_check_access); @@ -823,7 +825,7 @@ EXPORT_SYMBOL(__kcsan_check_access); void __tsan_read##size(void *ptr); \ void __tsan_read##size(void *ptr) \ { \ - check_access(ptr, size, 0); \ + check_access(ptr, size, 0, _RET_IP_); \ } \ EXPORT_SYMBOL(__tsan_read##size); \ void __tsan_unaligned_read##size(void *ptr) \ @@ -832,7 +834,7 @@ EXPORT_SYMBOL(__kcsan_check_access); void __tsan_write##size(void *ptr); \ void __tsan_write##size(void *ptr) \ { \ - check_access(ptr, size, KCSAN_ACCESS_WRITE); \ + check_access(ptr, size, KCSAN_ACCESS_WRITE, _RET_IP_); \ } \ EXPORT_SYMBOL(__tsan_write##size); \ void __tsan_unaligned_write##size(void *ptr) \ @@ -842,7 +844,8 @@ EXPORT_SYMBOL(__kcsan_check_access); void __tsan_read_write##size(void *ptr) \ { \ check_access(ptr, size, \ - KCSAN_ACCESS_COMPOUND | KCSAN_ACCESS_WRITE); \ + KCSAN_ACCESS_COMPOUND | KCSAN_ACCESS_WRITE, \ + _RET_IP_); \ } \ EXPORT_SYMBOL(__tsan_read_write##size); \ void __tsan_unaligned_read_write##size(void *ptr) \ @@ -858,14 +861,14 @@ DEFINE_TSAN_READ_WRITE(16); void __tsan_read_range(void *ptr, size_t size); void __tsan_read_range(void *ptr, size_t size) { - check_access(ptr, size, 0); + check_access(ptr, size, 0, _RET_IP_); } EXPORT_SYMBOL(__tsan_read_range); void __tsan_write_range(void *ptr, size_t size); void __tsan_write_range(void *ptr, size_t size) { - check_access(ptr, size, KCSAN_ACCESS_WRITE); + check_access(ptr, size, KCSAN_ACCESS_WRITE, _RET_IP_); } EXPORT_SYMBOL(__tsan_write_range); @@ -886,7 +889,8 @@ EXPORT_SYMBOL(__tsan_write_range); IS_ALIGNED((unsigned long)ptr, size); \ if (IS_ENABLED(CONFIG_KCSAN_IGNORE_ATOMICS) && is_atomic) \ return; \ - check_access(ptr, size, is_atomic ? KCSAN_ACCESS_ATOMIC : 0); \ + check_access(ptr, size, is_atomic ? KCSAN_ACCESS_ATOMIC : 0, \ + _RET_IP_); \ } \ EXPORT_SYMBOL(__tsan_volatile_read##size); \ void __tsan_unaligned_volatile_read##size(void *ptr) \ @@ -901,7 +905,8 @@ EXPORT_SYMBOL(__tsan_write_range); return; \ check_access(ptr, size, \ KCSAN_ACCESS_WRITE | \ - (is_atomic ? KCSAN_ACCESS_ATOMIC : 0)); \ + (is_atomic ? KCSAN_ACCESS_ATOMIC : 0), \ + _RET_IP_); \ } \ EXPORT_SYMBOL(__tsan_volatile_write##size); \ void __tsan_unaligned_volatile_write##size(void *ptr) \ @@ -955,7 +960,7 @@ EXPORT_SYMBOL(__tsan_init); u##bits __tsan_atomic##bits##_load(const u##bits *ptr, int memorder) \ { \ if (!IS_ENABLED(CONFIG_KCSAN_IGNORE_ATOMICS)) { \ - check_access(ptr, bits / BITS_PER_BYTE, KCSAN_ACCESS_ATOMIC); \ + check_access(ptr, bits / BITS_PER_BYTE, KCSAN_ACCESS_ATOMIC, _RET_IP_); \ } \ return __atomic_load_n(ptr, memorder); \ } \ @@ -965,7 +970,7 @@ EXPORT_SYMBOL(__tsan_init); { \ if (!IS_ENABLED(CONFIG_KCSAN_IGNORE_ATOMICS)) { \ check_access(ptr, bits / BITS_PER_BYTE, \ - KCSAN_ACCESS_WRITE | KCSAN_ACCESS_ATOMIC); \ + KCSAN_ACCESS_WRITE | KCSAN_ACCESS_ATOMIC, _RET_IP_); \ } \ __atomic_store_n(ptr, v, memorder); \ } \ @@ -978,7 +983,7 @@ EXPORT_SYMBOL(__tsan_init); if (!IS_ENABLED(CONFIG_KCSAN_IGNORE_ATOMICS)) { \ check_access(ptr, bits / BITS_PER_BYTE, \ KCSAN_ACCESS_COMPOUND | KCSAN_ACCESS_WRITE | \ - KCSAN_ACCESS_ATOMIC); \ + KCSAN_ACCESS_ATOMIC, _RET_IP_); \ } \ return __atomic_##op##suffix(ptr, v, memorder); \ } \ @@ -1010,7 +1015,7 @@ EXPORT_SYMBOL(__tsan_init); if (!IS_ENABLED(CONFIG_KCSAN_IGNORE_ATOMICS)) { \ check_access(ptr, bits / BITS_PER_BYTE, \ KCSAN_ACCESS_COMPOUND | KCSAN_ACCESS_WRITE | \ - KCSAN_ACCESS_ATOMIC); \ + KCSAN_ACCESS_ATOMIC, _RET_IP_); \ } \ return __atomic_compare_exchange_n(ptr, exp, val, weak, mo, fail_mo); \ } \ @@ -1025,7 +1030,7 @@ EXPORT_SYMBOL(__tsan_init); if (!IS_ENABLED(CONFIG_KCSAN_IGNORE_ATOMICS)) { \ check_access(ptr, bits / BITS_PER_BYTE, \ KCSAN_ACCESS_COMPOUND | KCSAN_ACCESS_WRITE | \ - KCSAN_ACCESS_ATOMIC); \ + KCSAN_ACCESS_ATOMIC, _RET_IP_); \ } \ __atomic_compare_exchange_n(ptr, &exp, val, 0, mo, fail_mo); \ return exp; \ diff --git a/kernel/kcsan/kcsan.h b/kernel/kcsan/kcsan.h index f36e25c497ed..ae33c2a7f07e 100644 --- a/kernel/kcsan/kcsan.h +++ b/kernel/kcsan/kcsan.h @@ -121,7 +121,7 @@ enum kcsan_value_change { * to be consumed by the reporting thread. No report is printed yet. */ void kcsan_report_set_info(const volatile void *ptr, size_t size, int access_type, - int watchpoint_idx); + unsigned long ip, int watchpoint_idx); /* * The calling thread observed that the watchpoint it set up was hit and @@ -129,14 +129,14 @@ void kcsan_report_set_info(const volatile void *ptr, size_t size, int access_typ * thread. */ void kcsan_report_known_origin(const volatile void *ptr, size_t size, int access_type, - enum kcsan_value_change value_change, int watchpoint_idx, - u64 old, u64 new, u64 mask); + unsigned long ip, enum kcsan_value_change value_change, + int watchpoint_idx, u64 old, u64 new, u64 mask); /* * No other thread was observed to race with the access, but the data value * before and after the stall differs. Reports a race of "unknown origin". */ void kcsan_report_unknown_origin(const volatile void *ptr, size_t size, int access_type, - u64 old, u64 new, u64 mask); + unsigned long ip, u64 old, u64 new, u64 mask); #endif /* _KERNEL_KCSAN_KCSAN_H */ diff --git a/kernel/kcsan/report.c b/kernel/kcsan/report.c index 21137929d428..50c4119f5cc0 100644 --- a/kernel/kcsan/report.c +++ b/kernel/kcsan/report.c @@ -31,6 +31,7 @@ struct access_info { int access_type; int task_pid; int cpu_id; + unsigned long ip; }; /* @@ -576,21 +577,22 @@ discard: } static struct access_info prepare_access_info(const volatile void *ptr, size_t size, - int access_type) + int access_type, unsigned long ip) { return (struct access_info) { .ptr = ptr, .size = size, .access_type = access_type, .task_pid = in_task() ? task_pid_nr(current) : -1, - .cpu_id = raw_smp_processor_id() + .cpu_id = raw_smp_processor_id(), + .ip = ip, }; } void kcsan_report_set_info(const volatile void *ptr, size_t size, int access_type, - int watchpoint_idx) + unsigned long ip, int watchpoint_idx) { - const struct access_info ai = prepare_access_info(ptr, size, access_type); + const struct access_info ai = prepare_access_info(ptr, size, access_type, ip); unsigned long flags; kcsan_disable_current(); @@ -603,10 +605,10 @@ void kcsan_report_set_info(const volatile void *ptr, size_t size, int access_typ } void kcsan_report_known_origin(const volatile void *ptr, size_t size, int access_type, - enum kcsan_value_change value_change, int watchpoint_idx, - u64 old, u64 new, u64 mask) + unsigned long ip, enum kcsan_value_change value_change, + int watchpoint_idx, u64 old, u64 new, u64 mask) { - const struct access_info ai = prepare_access_info(ptr, size, access_type); + const struct access_info ai = prepare_access_info(ptr, size, access_type, ip); struct other_info *other_info = &other_infos[watchpoint_idx]; unsigned long flags = 0; @@ -637,9 +639,9 @@ out: } void kcsan_report_unknown_origin(const volatile void *ptr, size_t size, int access_type, - u64 old, u64 new, u64 mask) + unsigned long ip, u64 old, u64 new, u64 mask) { - const struct access_info ai = prepare_access_info(ptr, size, access_type); + const struct access_info ai = prepare_access_info(ptr, size, access_type, ip); unsigned long flags; kcsan_disable_current(); -- cgit