X-Git-Url: http://git.liburcu.org/?a=blobdiff_plain;f=lttng-syscalls.c;h=70d2c323ce9207b191313488a87d80b464075b7b;hb=refs%2Fheads%2Fstable-2.7;hp=5023c2f9dcc2ff8c588ad159303255dabab92ac6;hpb=cb3ef14c052adc12da2b9e26aebf9fc6e7d82fa3;p=lttng-modules.git diff --git a/lttng-syscalls.c b/lttng-syscalls.c index 5023c2f9..70d2c323 100644 --- a/lttng-syscalls.c +++ b/lttng-syscalls.c @@ -27,10 +27,17 @@ #include #include #include +#include +#include +#include +#include #include #include +#include "lib/bitfield.h" #include "wrapper/tracepoint.h" +#include "wrapper/file.h" +#include "wrapper/rcu.h" #include "lttng-events.h" #ifndef CONFIG_COMPAT @@ -39,6 +46,11 @@ # endif #endif +/* in_compat_syscall appears in kernel 4.6. */ +#ifndef in_compat_syscall + #define in_compat_syscall() is_compat_task() +#endif + enum sc_type { SC_TYPE_ENTRY, SC_TYPE_EXIT, @@ -46,10 +58,15 @@ enum sc_type { SC_TYPE_COMPAT_EXIT, }; -#define SYSCALL_ENTRY_STR "syscall_entry_" -#define COMPAT_SYSCALL_ENTRY_STR "compat_syscall_entry_" -#define SYSCALL_EXIT_STR "syscall_exit_" -#define COMPAT_SYSCALL_EXIT_STR "compat_syscall_exit_" +#define SYSCALL_ENTRY_TOK syscall_entry_ +#define COMPAT_SYSCALL_ENTRY_TOK compat_syscall_entry_ +#define SYSCALL_EXIT_TOK syscall_exit_ +#define COMPAT_SYSCALL_EXIT_TOK compat_syscall_exit_ + +#define SYSCALL_ENTRY_STR __stringify(SYSCALL_ENTRY_TOK) +#define COMPAT_SYSCALL_ENTRY_STR __stringify(COMPAT_SYSCALL_ENTRY_TOK) +#define SYSCALL_EXIT_STR __stringify(SYSCALL_EXIT_TOK) +#define COMPAT_SYSCALL_EXIT_STR __stringify(COMPAT_SYSCALL_EXIT_TOK) static void syscall_entry_probe(void *__data, struct pt_regs *regs, long id); @@ -65,6 +82,7 @@ struct oldold_utsname; struct old_utsname; struct sel_arg_struct; struct mmap_arg_struct; +struct file_handle; #ifdef IA32_NR_syscalls #define NR_compat_syscalls IA32_NR_syscalls @@ -83,6 +101,7 @@ struct mmap_arg_struct; #define PARAMS(args...) args /* Handle unknown syscalls */ +#undef TRACE_SYSTEM #define TRACE_SYSTEM syscalls_unknown #include "instrumentation/syscalls/headers/syscalls_unknown.h" #undef TRACE_SYSTEM @@ -101,25 +120,24 @@ struct mmap_arg_struct; /* Hijack probe callback for system call enter */ #undef TP_PROBE_CB #define TP_PROBE_CB(_template) &syscall_entry_probe -#define SC_LTTNG_TRACEPOINT_EVENT(_name, _proto, _args, _struct, _assign, _printk) \ - LTTNG_TRACEPOINT_EVENT(syscall_enter_##_name, PARAMS(_proto), PARAMS(_args), \ - PARAMS(_struct), PARAMS(_assign), PARAMS(_printk)) -#define SC_LTTNG_TRACEPOINT_EVENT_CODE(_name, _proto, _args, _locvar, _code, _struct, _assign, _printk) \ - LTTNG_TRACEPOINT_EVENT_CODE(syscall_enter_##_name, PARAMS(_proto), PARAMS(_args), \ +#define SC_LTTNG_TRACEPOINT_EVENT(_name, _proto, _args, _fields) \ + LTTNG_TRACEPOINT_EVENT(syscall_entry_##_name, PARAMS(_proto), PARAMS(_args), \ + PARAMS(_fields)) +#define SC_LTTNG_TRACEPOINT_EVENT_CODE(_name, _proto, _args, _locvar, _code, _fields) \ + LTTNG_TRACEPOINT_EVENT_CODE(syscall_entry_##_name, PARAMS(_proto), PARAMS(_args), \ PARAMS(_locvar), PARAMS(_code), \ - PARAMS(_struct), PARAMS(_assign), PARAMS(_printk)) -#define SC_LTTNG_TRACEPOINT_EVENT_CLASS_NOARGS(_name, _struct, _assign, _printk) \ - LTTNG_TRACEPOINT_EVENT_CLASS_NOARGS(syscall_enter_##_name, PARAMS(_struct), PARAMS(_assign), \ - PARAMS(_printk)) + PARAMS(_fields)) +#define SC_LTTNG_TRACEPOINT_EVENT_CLASS_NOARGS(_name, _fields) \ + LTTNG_TRACEPOINT_EVENT_CLASS_NOARGS(syscall_entry_##_name, PARAMS(_fields)) #define SC_LTTNG_TRACEPOINT_EVENT_INSTANCE_NOARGS(_template, _name) \ - LTTNG_TRACEPOINT_EVENT_INSTANCE_NOARGS(syscall_enter_##_template, syscall_enter_##_name) + LTTNG_TRACEPOINT_EVENT_INSTANCE_NOARGS(syscall_entry_##_template, syscall_entry_##_name) #undef TRACE_SYSTEM -#define TRACE_SYSTEM syscall_enter_integers +#define TRACE_SYSTEM syscall_entry_integers #define TRACE_INCLUDE_FILE syscalls_integers #include "instrumentation/syscalls/headers/syscalls_integers.h" #undef TRACE_INCLUDE_FILE #undef TRACE_SYSTEM -#define TRACE_SYSTEM syscall_enter_pointers +#define TRACE_SYSTEM syscall_entry_pointers #define TRACE_INCLUDE_FILE syscalls_pointers #include "instrumentation/syscalls/headers/syscalls_pointers.h" #undef TRACE_INCLUDE_FILE @@ -134,26 +152,23 @@ struct mmap_arg_struct; /* Hijack probe callback for compat system call enter */ #define TP_PROBE_CB(_template) &syscall_entry_probe -#define SC_LTTNG_TRACEPOINT_EVENT(_name, _proto, _args, _struct, _assign, _printk) \ - LTTNG_TRACEPOINT_EVENT(compat_syscall_enter_##_name, PARAMS(_proto), PARAMS(_args), \ - PARAMS(_struct), PARAMS(_assign), \ - PARAMS(_printk)) -#define SC_LTTNG_TRACEPOINT_EVENT_CODE(_name, _proto, _args, _locvar, _code, _struct, _assign, _printk) \ - LTTNG_TRACEPOINT_EVENT_CODE(compat_syscall_enter_##_name, PARAMS(_proto), PARAMS(_args), \ - PARAMS(_locvar), PARAMS(_code), \ - PARAMS(_struct), PARAMS(_assign), PARAMS(_printk)) -#define SC_LTTNG_TRACEPOINT_EVENT_CLASS_NOARGS(_name, _struct, _assign, _printk) \ - LTTNG_TRACEPOINT_EVENT_CLASS_NOARGS(compat_syscall_enter_##_name, PARAMS(_struct), \ - PARAMS(_assign), PARAMS(_printk)) +#define SC_LTTNG_TRACEPOINT_EVENT(_name, _proto, _args, _fields) \ + LTTNG_TRACEPOINT_EVENT(compat_syscall_entry_##_name, PARAMS(_proto), PARAMS(_args), \ + PARAMS(_fields)) +#define SC_LTTNG_TRACEPOINT_EVENT_CODE(_name, _proto, _args, _locvar, _code, _fields) \ + LTTNG_TRACEPOINT_EVENT_CODE(compat_syscall_entry_##_name, PARAMS(_proto), PARAMS(_args), \ + PARAMS(_locvar), PARAMS(_code), PARAMS(_fields)) +#define SC_LTTNG_TRACEPOINT_EVENT_CLASS_NOARGS(_name, _fields) \ + LTTNG_TRACEPOINT_EVENT_CLASS_NOARGS(compat_syscall_entry_##_name, PARAMS(_fields)) #define SC_LTTNG_TRACEPOINT_EVENT_INSTANCE_NOARGS(_template, _name) \ - LTTNG_TRACEPOINT_EVENT_INSTANCE_NOARGS(compat_syscall_enter_##_template, \ - compat_syscall_enter_##_name) -#define TRACE_SYSTEM compat_syscall_enter_integers + LTTNG_TRACEPOINT_EVENT_INSTANCE_NOARGS(compat_syscall_entry_##_template, \ + compat_syscall_entry_##_name) +#define TRACE_SYSTEM compat_syscall_entry_integers #define TRACE_INCLUDE_FILE compat_syscalls_integers #include "instrumentation/syscalls/headers/compat_syscalls_integers.h" #undef TRACE_INCLUDE_FILE #undef TRACE_SYSTEM -#define TRACE_SYSTEM compat_syscall_enter_pointers +#define TRACE_SYSTEM compat_syscall_entry_pointers #define TRACE_INCLUDE_FILE compat_syscalls_pointers #include "instrumentation/syscalls/headers/compat_syscalls_pointers.h" #undef TRACE_INCLUDE_FILE @@ -181,16 +196,14 @@ struct mmap_arg_struct; /* Hijack probe callback for system call exit */ #define TP_PROBE_CB(_template) &syscall_exit_probe -#define SC_LTTNG_TRACEPOINT_EVENT(_name, _proto, _args, _struct, _assign, _printk) \ +#define SC_LTTNG_TRACEPOINT_EVENT(_name, _proto, _args, _fields) \ LTTNG_TRACEPOINT_EVENT(syscall_exit_##_name, PARAMS(_proto), PARAMS(_args), \ - PARAMS(_struct), PARAMS(_assign), PARAMS(_printk)) -#define SC_LTTNG_TRACEPOINT_EVENT_CODE(_name, _proto, _args, _locvar, _code, _struct, _assign, _printk) \ + PARAMS(_fields)) +#define SC_LTTNG_TRACEPOINT_EVENT_CODE(_name, _proto, _args, _locvar, _code, _fields) \ LTTNG_TRACEPOINT_EVENT_CODE(syscall_exit_##_name, PARAMS(_proto), PARAMS(_args), \ - PARAMS(_locvar), PARAMS(_code), \ - PARAMS(_struct), PARAMS(_assign), PARAMS(_printk)) -#define SC_LTTNG_TRACEPOINT_EVENT_CLASS_NOARGS(_name, _struct, _assign, _printk) \ - LTTNG_TRACEPOINT_EVENT_CLASS_NOARGS(syscall_exit_##_name, PARAMS(_struct), \ - PARAMS(_assign), PARAMS(_printk)) + PARAMS(_locvar), PARAMS(_code), PARAMS(_fields)) +#define SC_LTTNG_TRACEPOINT_EVENT_CLASS_NOARGS(_name, _fields) \ + LTTNG_TRACEPOINT_EVENT_CLASS_NOARGS(syscall_exit_##_name, PARAMS(_fields)) #define SC_LTTNG_TRACEPOINT_EVENT_INSTANCE_NOARGS(_template, _name) \ LTTNG_TRACEPOINT_EVENT_INSTANCE_NOARGS(syscall_exit_##_template, \ syscall_exit_##_name) @@ -215,16 +228,14 @@ struct mmap_arg_struct; /* Hijack probe callback for compat system call exit */ #define TP_PROBE_CB(_template) &syscall_exit_probe -#define SC_LTTNG_TRACEPOINT_EVENT(_name, _proto, _args, _struct, _assign, _printk) \ +#define SC_LTTNG_TRACEPOINT_EVENT(_name, _proto, _args, _fields) \ LTTNG_TRACEPOINT_EVENT(compat_syscall_exit_##_name, PARAMS(_proto), PARAMS(_args), \ - PARAMS(_struct), PARAMS(_assign), PARAMS(_printk)) -#define SC_LTTNG_TRACEPOINT_EVENT_CODE(_name, _proto, _args, _locvar, _code, _struct, _assign, _printk) \ + PARAMS(_fields)) +#define SC_LTTNG_TRACEPOINT_EVENT_CODE(_name, _proto, _args, _locvar, _code, _fields) \ LTTNG_TRACEPOINT_EVENT_CODE(compat_syscall_exit_##_name, PARAMS(_proto), PARAMS(_args), \ - PARAMS(_locvar), PARAMS(_code), \ - PARAMS(_struct), PARAMS(_assign), PARAMS(_printk)) -#define SC_LTTNG_TRACEPOINT_EVENT_CLASS_NOARGS(_name, _struct, _assign, _printk) \ - LTTNG_TRACEPOINT_EVENT_CLASS_NOARGS(compat_syscall_exit_##_name, PARAMS(_struct), \ - PARAMS(_assign), PARAMS(_printk)) + PARAMS(_locvar), PARAMS(_code), PARAMS(_fields)) +#define SC_LTTNG_TRACEPOINT_EVENT_CLASS_NOARGS(_name, _fields) \ + LTTNG_TRACEPOINT_EVENT_CLASS_NOARGS(compat_syscall_exit_##_name, PARAMS(_fields)) #define SC_LTTNG_TRACEPOINT_EVENT_INSTANCE_NOARGS(_template, _name) \ LTTNG_TRACEPOINT_EVENT_INSTANCE_NOARGS(compat_syscall_exit_##_template, \ compat_syscall_exit_##_name) @@ -269,10 +280,10 @@ struct trace_syscall_entry { #undef TRACE_SYSCALL_TABLE #define TRACE_SYSCALL_TABLE(_template, _name, _nr, _nrargs) \ [ _nr ] = { \ - .func = __event_probe__syscall_enter_##_template, \ + .func = __event_probe__syscall_entry_##_template, \ .nrargs = (_nrargs), \ - .fields = __event_fields___syscall_enter_##_template, \ - .desc = &__event_desc___syscall_enter_##_name, \ + .fields = __event_fields___syscall_entry_##_template, \ + .desc = &__event_desc___syscall_entry_##_name, \ }, /* Syscall enter tracing table */ @@ -284,10 +295,10 @@ static const struct trace_syscall_entry sc_table[] = { #undef TRACE_SYSCALL_TABLE #define TRACE_SYSCALL_TABLE(_template, _name, _nr, _nrargs) \ [ _nr ] = { \ - .func = __event_probe__compat_syscall_enter_##_template, \ + .func = __event_probe__compat_syscall_entry_##_template, \ .nrargs = (_nrargs), \ - .fields = __event_fields___compat_syscall_enter_##_template, \ - .desc = &__event_desc___compat_syscall_enter_##_name, \ + .fields = __event_fields___compat_syscall_entry_##_template, \ + .desc = &__event_desc___compat_syscall_entry_##_name, \ }, /* Compat syscall enter table */ @@ -348,10 +359,10 @@ static void syscall_entry_unknown(struct lttng_event *event, unsigned long args[UNKNOWN_SYSCALL_NRARGS]; syscall_get_arguments(current, regs, 0, UNKNOWN_SYSCALL_NRARGS, args); - if (unlikely(is_compat_task())) - __event_probe__compat_syscall_enter_unknown(event, id, args); + if (unlikely(in_compat_syscall())) + __event_probe__compat_syscall_entry_unknown(event, id, args); else - __event_probe__syscall_enter_unknown(event, id, args); + __event_probe__syscall_entry_unknown(event, id, args); } void syscall_entry_probe(void *__data, struct pt_regs *regs, long id) @@ -361,12 +372,12 @@ void syscall_entry_probe(void *__data, struct pt_regs *regs, long id) const struct trace_syscall_entry *table, *entry; size_t table_len; - if (unlikely(is_compat_task())) { + if (unlikely(in_compat_syscall())) { struct lttng_syscall_filter *filter; - filter = rcu_dereference(chan->sc_filter); + filter = lttng_rcu_dereference(chan->sc_filter); if (filter) { - if (id >= NR_compat_syscalls + if (id < 0 || id >= NR_compat_syscalls || !test_bit(id, filter->sc_compat)) { /* System call filtered out. */ return; @@ -378,9 +389,9 @@ void syscall_entry_probe(void *__data, struct pt_regs *regs, long id) } else { struct lttng_syscall_filter *filter; - filter = rcu_dereference(chan->sc_filter); + filter = lttng_rcu_dereference(chan->sc_filter); if (filter) { - if (id >= NR_syscalls + if (id < 0 || id >= NR_syscalls || !test_bit(id, filter->sc)) { /* System call filtered out. */ return; @@ -390,11 +401,11 @@ void syscall_entry_probe(void *__data, struct pt_regs *regs, long id) table_len = ARRAY_SIZE(sc_table); unknown_event = chan->sc_unknown; } - if (unlikely(id >= table_len)) { + if (unlikely(id < 0 || id >= table_len)) { syscall_entry_unknown(unknown_event, regs, id); return; } - if (unlikely(is_compat_task())) + if (unlikely(in_compat_syscall())) event = chan->compat_sc_table[id]; else event = chan->sc_table[id]; @@ -494,12 +505,12 @@ void syscall_entry_probe(void *__data, struct pt_regs *regs, long id) } static void syscall_exit_unknown(struct lttng_event *event, - struct pt_regs *regs, unsigned int id, long ret) + struct pt_regs *regs, int id, long ret) { unsigned long args[UNKNOWN_SYSCALL_NRARGS]; syscall_get_arguments(current, regs, 0, UNKNOWN_SYSCALL_NRARGS, args); - if (unlikely(is_compat_task())) + if (unlikely(in_compat_syscall())) __event_probe__compat_syscall_exit_unknown(event, id, ret, args); else @@ -515,12 +526,12 @@ void syscall_exit_probe(void *__data, struct pt_regs *regs, long ret) long id; id = syscall_get_nr(current, regs); - if (unlikely(is_compat_task())) { + if (unlikely(in_compat_syscall())) { struct lttng_syscall_filter *filter; - filter = rcu_dereference(chan->sc_filter); + filter = lttng_rcu_dereference(chan->sc_filter); if (filter) { - if (id >= NR_compat_syscalls + if (id < 0 || id >= NR_compat_syscalls || !test_bit(id, filter->sc_compat)) { /* System call filtered out. */ return; @@ -532,9 +543,9 @@ void syscall_exit_probe(void *__data, struct pt_regs *regs, long ret) } else { struct lttng_syscall_filter *filter; - filter = rcu_dereference(chan->sc_filter); + filter = lttng_rcu_dereference(chan->sc_filter); if (filter) { - if (id >= NR_syscalls + if (id < 0 || id >= NR_syscalls || !test_bit(id, filter->sc)) { /* System call filtered out. */ return; @@ -544,11 +555,11 @@ void syscall_exit_probe(void *__data, struct pt_regs *regs, long ret) table_len = ARRAY_SIZE(sc_exit_table); unknown_event = chan->sc_exit_unknown; } - if (unlikely(id >= table_len)) { + if (unlikely(id < 0 || id >= table_len)) { syscall_exit_unknown(unknown_event, regs, id, ret); return; } - if (unlikely(is_compat_task())) + if (unlikely(in_compat_syscall())) event = chan->compat_sc_exit_table[id]; else event = chan->sc_exit_table[id]; @@ -654,7 +665,10 @@ void syscall_exit_probe(void *__data, struct pt_regs *regs, long ret) } } -/* noinline to diminish caller stack size */ +/* + * noinline to diminish caller stack size. + * Should be called with sessions lock held. + */ static int fill_table(const struct trace_syscall_entry *table, size_t table_len, struct lttng_event **chan_table, struct lttng_channel *chan, @@ -703,9 +717,9 @@ int fill_table(const struct trace_syscall_entry *table, size_t table_len, strncat(ev.name, desc->name, LTTNG_KERNEL_SYM_NAME_LEN - strlen(ev.name) - 1); ev.name[LTTNG_KERNEL_SYM_NAME_LEN - 1] = '\0'; - ev.instrumentation = LTTNG_KERNEL_NOOP; - chan_table[i] = lttng_event_create(chan, &ev, filter, - desc); + ev.instrumentation = LTTNG_KERNEL_SYSCALL; + chan_table[i] = _lttng_event_create(chan, &ev, filter, + desc, ev.instrumentation); WARN_ON_ONCE(!chan_table[i]); if (IS_ERR(chan_table[i])) { /* @@ -720,6 +734,9 @@ int fill_table(const struct trace_syscall_entry *table, size_t table_len, return 0; } +/* + * Should be called with sessions lock held. + */ int lttng_syscalls_register(struct lttng_channel *chan, void *filter) { struct lttng_kernel_event ev; @@ -762,14 +779,15 @@ int lttng_syscalls_register(struct lttng_channel *chan, void *filter) #endif if (!chan->sc_unknown) { const struct lttng_event_desc *desc = - &__event_desc___syscall_enter_unknown; + &__event_desc___syscall_entry_unknown; memset(&ev, 0, sizeof(ev)); strncpy(ev.name, desc->name, LTTNG_KERNEL_SYM_NAME_LEN); ev.name[LTTNG_KERNEL_SYM_NAME_LEN - 1] = '\0'; - ev.instrumentation = LTTNG_KERNEL_NOOP; - chan->sc_unknown = lttng_event_create(chan, &ev, filter, - desc); + ev.instrumentation = LTTNG_KERNEL_SYSCALL; + chan->sc_unknown = _lttng_event_create(chan, &ev, filter, + desc, + ev.instrumentation); WARN_ON_ONCE(!chan->sc_unknown); if (IS_ERR(chan->sc_unknown)) { return PTR_ERR(chan->sc_unknown); @@ -778,14 +796,15 @@ int lttng_syscalls_register(struct lttng_channel *chan, void *filter) if (!chan->sc_compat_unknown) { const struct lttng_event_desc *desc = - &__event_desc___compat_syscall_enter_unknown; + &__event_desc___compat_syscall_entry_unknown; memset(&ev, 0, sizeof(ev)); strncpy(ev.name, desc->name, LTTNG_KERNEL_SYM_NAME_LEN); ev.name[LTTNG_KERNEL_SYM_NAME_LEN - 1] = '\0'; - ev.instrumentation = LTTNG_KERNEL_NOOP; - chan->sc_compat_unknown = lttng_event_create(chan, &ev, filter, - desc); + ev.instrumentation = LTTNG_KERNEL_SYSCALL; + chan->sc_compat_unknown = _lttng_event_create(chan, &ev, filter, + desc, + ev.instrumentation); WARN_ON_ONCE(!chan->sc_unknown); if (IS_ERR(chan->sc_compat_unknown)) { return PTR_ERR(chan->sc_compat_unknown); @@ -799,9 +818,10 @@ int lttng_syscalls_register(struct lttng_channel *chan, void *filter) memset(&ev, 0, sizeof(ev)); strncpy(ev.name, desc->name, LTTNG_KERNEL_SYM_NAME_LEN); ev.name[LTTNG_KERNEL_SYM_NAME_LEN - 1] = '\0'; - ev.instrumentation = LTTNG_KERNEL_NOOP; - chan->compat_sc_exit_unknown = lttng_event_create(chan, &ev, - filter, desc); + ev.instrumentation = LTTNG_KERNEL_SYSCALL; + chan->compat_sc_exit_unknown = _lttng_event_create(chan, &ev, + filter, desc, + ev.instrumentation); WARN_ON_ONCE(!chan->compat_sc_exit_unknown); if (IS_ERR(chan->compat_sc_exit_unknown)) { return PTR_ERR(chan->compat_sc_exit_unknown); @@ -815,9 +835,9 @@ int lttng_syscalls_register(struct lttng_channel *chan, void *filter) memset(&ev, 0, sizeof(ev)); strncpy(ev.name, desc->name, LTTNG_KERNEL_SYM_NAME_LEN); ev.name[LTTNG_KERNEL_SYM_NAME_LEN - 1] = '\0'; - ev.instrumentation = LTTNG_KERNEL_NOOP; - chan->sc_exit_unknown = lttng_event_create(chan, &ev, filter, - desc); + ev.instrumentation = LTTNG_KERNEL_SYSCALL; + chan->sc_exit_unknown = _lttng_event_create(chan, &ev, filter, + desc, ev.instrumentation); WARN_ON_ONCE(!chan->sc_exit_unknown); if (IS_ERR(chan->sc_exit_unknown)) { return PTR_ERR(chan->sc_exit_unknown); @@ -949,6 +969,12 @@ int get_compat_syscall_nr(const char *syscall_name) return syscall_nr; } +static +uint32_t get_sc_tables_len(void) +{ + return ARRAY_SIZE(sc_table) + ARRAY_SIZE(compat_sc_table); +} + int lttng_syscall_filter_enable(struct lttng_channel *chan, const char *name) { @@ -1022,6 +1048,8 @@ int lttng_syscall_filter_disable(struct lttng_channel *chan, WARN_ON_ONCE(!chan->sc_table); if (!chan->sc_filter) { + if (!chan->syscall_all) + return -EEXIST; filter = kzalloc(sizeof(struct lttng_syscall_filter), GFP_KERNEL); if (!filter) @@ -1033,6 +1061,20 @@ int lttng_syscall_filter_disable(struct lttng_channel *chan, filter = chan->sc_filter; } + if (!name) { + /* Fail if all syscalls are already disabled. */ + if (bitmap_empty(filter->sc, NR_syscalls) + && bitmap_empty(filter->sc_compat, + NR_compat_syscalls)) { + ret = -EEXIST; + goto error; + } + + /* Disable all system calls */ + bitmap_clear(filter->sc, 0, NR_syscalls); + bitmap_clear(filter->sc_compat, 0, NR_compat_syscalls); + goto apply_filter; + } syscall_nr = get_syscall_nr(name); compat_syscall_nr = get_compat_syscall_nr(name); if (syscall_nr < 0 && compat_syscall_nr < 0) { @@ -1040,19 +1082,20 @@ int lttng_syscall_filter_disable(struct lttng_channel *chan, goto error; } if (syscall_nr >= 0) { - if (!test_bit(syscall_nr, chan->sc_filter->sc)) { + if (!test_bit(syscall_nr, filter->sc)) { ret = -EEXIST; goto error; } - bitmap_clear(chan->sc_filter->sc, syscall_nr, 1); + bitmap_clear(filter->sc, syscall_nr, 1); } if (compat_syscall_nr >= 0) { - if (!test_bit(compat_syscall_nr, chan->sc_filter->sc_compat)) { + if (!test_bit(compat_syscall_nr, filter->sc_compat)) { ret = -EEXIST; goto error; } - bitmap_clear(chan->sc_filter->sc_compat, compat_syscall_nr, 1); + bitmap_clear(filter->sc_compat, compat_syscall_nr, 1); } +apply_filter: if (!chan->sc_filter) rcu_assign_pointer(chan->sc_filter, filter); chan->syscall_all = 0; @@ -1063,3 +1106,201 @@ error: kfree(filter); return ret; } + +static +const struct trace_syscall_entry *syscall_list_get_entry(loff_t *pos) +{ + const struct trace_syscall_entry *entry; + int iter = 0; + + for (entry = sc_table; + entry < sc_table + ARRAY_SIZE(sc_table); + entry++) { + if (iter++ >= *pos) + return entry; + } + for (entry = compat_sc_table; + entry < compat_sc_table + ARRAY_SIZE(compat_sc_table); + entry++) { + if (iter++ >= *pos) + return entry; + } + /* End of list */ + return NULL; +} + +static +void *syscall_list_start(struct seq_file *m, loff_t *pos) +{ + return (void *) syscall_list_get_entry(pos); +} + +static +void *syscall_list_next(struct seq_file *m, void *p, loff_t *ppos) +{ + (*ppos)++; + return (void *) syscall_list_get_entry(ppos); +} + +static +void syscall_list_stop(struct seq_file *m, void *p) +{ +} + +static +int get_sc_table(const struct trace_syscall_entry *entry, + const struct trace_syscall_entry **table, + unsigned int *bitness) +{ + if (entry >= sc_table && entry < sc_table + ARRAY_SIZE(sc_table)) { + if (bitness) + *bitness = BITS_PER_LONG; + if (table) + *table = sc_table; + return 0; + } + if (!(entry >= compat_sc_table + && entry < compat_sc_table + ARRAY_SIZE(compat_sc_table))) { + return -EINVAL; + } + if (bitness) + *bitness = 32; + if (table) + *table = compat_sc_table; + return 0; +} + +static +int syscall_list_show(struct seq_file *m, void *p) +{ + const struct trace_syscall_entry *table, *entry = p; + unsigned int bitness; + unsigned long index; + int ret; + const char *name; + + ret = get_sc_table(entry, &table, &bitness); + if (ret) + return ret; + if (!entry->desc) + return 0; + if (table == sc_table) { + index = entry - table; + name = &entry->desc->name[strlen(SYSCALL_ENTRY_STR)]; + } else { + index = (entry - table) + ARRAY_SIZE(sc_table); + name = &entry->desc->name[strlen(COMPAT_SYSCALL_ENTRY_STR)]; + } + seq_printf(m, "syscall { index = %lu; name = %s; bitness = %u; };\n", + index, name, bitness); + return 0; +} + +static +const struct seq_operations lttng_syscall_list_seq_ops = { + .start = syscall_list_start, + .next = syscall_list_next, + .stop = syscall_list_stop, + .show = syscall_list_show, +}; + +static +int lttng_syscall_list_open(struct inode *inode, struct file *file) +{ + return seq_open(file, <tng_syscall_list_seq_ops); +} + +const struct file_operations lttng_syscall_list_fops = { + .owner = THIS_MODULE, + .open = lttng_syscall_list_open, + .read = seq_read, + .llseek = seq_lseek, + .release = seq_release, +}; + +long lttng_channel_syscall_mask(struct lttng_channel *channel, + struct lttng_kernel_syscall_mask __user *usyscall_mask) +{ + uint32_t len, sc_tables_len, bitmask_len; + int ret = 0, bit; + char *tmp_mask; + struct lttng_syscall_filter *filter; + + ret = get_user(len, &usyscall_mask->len); + if (ret) + return ret; + sc_tables_len = get_sc_tables_len(); + bitmask_len = ALIGN(sc_tables_len, 8) >> 3; + if (len < sc_tables_len) { + return put_user(sc_tables_len, &usyscall_mask->len); + } + /* Array is large enough, we can copy array to user-space. */ + tmp_mask = kzalloc(bitmask_len, GFP_KERNEL); + if (!tmp_mask) + return -ENOMEM; + filter = channel->sc_filter; + + for (bit = 0; bit < ARRAY_SIZE(sc_table); bit++) { + bool state; + + if (channel->sc_table) { + if (filter) + state = test_bit(bit, filter->sc); + else + state = 1; + } else { + state = 0; + } + bt_bitfield_write_be(tmp_mask, char, bit, 1, state); + } + for (; bit < sc_tables_len; bit++) { + bool state; + + if (channel->compat_sc_table) { + if (filter) + state = test_bit(bit - ARRAY_SIZE(sc_table), + filter->sc_compat); + else + state = 1; + } else { + state = 0; + } + bt_bitfield_write_be(tmp_mask, char, bit, 1, state); + } + if (copy_to_user(usyscall_mask->mask, tmp_mask, bitmask_len)) + ret = -EFAULT; + kfree(tmp_mask); + return ret; +} + +int lttng_abi_syscall_list(void) +{ + struct file *syscall_list_file; + int file_fd, ret; + + file_fd = lttng_get_unused_fd(); + if (file_fd < 0) { + ret = file_fd; + goto fd_error; + } + + syscall_list_file = anon_inode_getfile("[lttng_syscall_list]", + <tng_syscall_list_fops, + NULL, O_RDWR); + if (IS_ERR(syscall_list_file)) { + ret = PTR_ERR(syscall_list_file); + goto file_error; + } + ret = lttng_syscall_list_fops.open(NULL, syscall_list_file); + if (ret < 0) + goto open_error; + fd_install(file_fd, syscall_list_file); + return file_fd; + +open_error: + fput(syscall_list_file); +file_error: + put_unused_fd(file_fd); +fd_error: + return ret; +}