From 672a2bf84061f0f19acfc5869f5b3689759a55a8 Mon Sep 17 00:00:00 2001 From: Song Chen Date: Fri, 30 Dec 2022 14:33:38 +0800 Subject: kernel/trace: Provide default impelentations defined in trace_probe_tmpl.h There are 6 function definitions in trace_probe_tmpl.h, they are: 1, fetch_store_strlen 2, fetch_store_string 3, fetch_store_strlen_user 4, fetch_store_string_user 5, probe_mem_read 6, probe_mem_read_user Every C file which includes trace_probe_tmpl.h has to implement them, otherwise it gets warnings and errors. However, some of them are identical, like kprobe and eprobe, as a result, there is a lot redundant code in those 2 files. This patch would like to provide default behaviors for those functions which kprobe and eprobe can share by just including trace_probe_kernel.h with trace_probe_tmpl.h together. It removes redundant code, increases readability, and more importantly, makes it easier to introduce a new feature based on trace probe (it's possible). Link: https://lore.kernel.org/all/1672382018-18347-1-git-send-email-chensong_2000@189.cn/ Signed-off-by: Song Chen Reported-by: kernel test robot Acked-by: Masami Hiramatsu (Google) Signed-off-by: Masami Hiramatsu (Google) --- kernel/trace/trace_eprobe.c | 55 ++------------------------------------- kernel/trace/trace_events_synth.c | 6 ++--- kernel/trace/trace_kprobe.c | 54 -------------------------------------- kernel/trace/trace_probe_kernel.h | 30 ++++++++++++++++----- 4 files changed, 29 insertions(+), 116 deletions(-) diff --git a/kernel/trace/trace_eprobe.c b/kernel/trace/trace_eprobe.c index 9d0ebcffb539..846546395d62 100644 --- a/kernel/trace/trace_eprobe.c +++ b/kernel/trace/trace_eprobe.c @@ -320,7 +320,8 @@ print_eprobe_event(struct trace_iterator *iter, int flags, return trace_handle_return(s); } -static unsigned long get_event_field(struct fetch_insn *code, void *rec) +static nokprobe_inline unsigned long +get_event_field(struct fetch_insn *code, void *rec) { struct ftrace_event_field *field = code->data; unsigned long val; @@ -454,58 +455,6 @@ process_fetch_insn(struct fetch_insn *code, void *rec, void *dest, } NOKPROBE_SYMBOL(process_fetch_insn) -/* Return the length of string -- including null terminal byte */ -static nokprobe_inline int -fetch_store_strlen_user(unsigned long addr) -{ - return kern_fetch_store_strlen_user(addr); -} - -/* Return the length of string -- including null terminal byte */ -static nokprobe_inline int -fetch_store_strlen(unsigned long addr) -{ - return kern_fetch_store_strlen(addr); -} - -/* - * Fetch a null-terminated string from user. Caller MUST set *(u32 *)buf - * with max length and relative data location. - */ -static nokprobe_inline int -fetch_store_string_user(unsigned long addr, void *dest, void *base) -{ - return kern_fetch_store_string_user(addr, dest, base); -} - -/* - * Fetch a null-terminated string. Caller MUST set *(u32 *)buf with max - * length and relative data location. - */ -static nokprobe_inline int -fetch_store_string(unsigned long addr, void *dest, void *base) -{ - return kern_fetch_store_string(addr, dest, base); -} - -static nokprobe_inline int -probe_mem_read_user(void *dest, void *src, size_t size) -{ - const void __user *uaddr = (__force const void __user *)src; - - return copy_from_user_nofault(dest, uaddr, size); -} - -static nokprobe_inline int -probe_mem_read(void *dest, void *src, size_t size) -{ -#ifdef CONFIG_ARCH_HAS_NON_OVERLAPPING_ADDRESS_SPACE - if ((unsigned long)src < TASK_SIZE) - return probe_mem_read_user(dest, src, size); -#endif - return copy_from_kernel_nofault(dest, src, size); -} - /* eprobe handler */ static inline void __eprobe_trace_func(struct eprobe_data *edata, void *rec) diff --git a/kernel/trace/trace_events_synth.c b/kernel/trace/trace_events_synth.c index 67592eed0be8..76590f50930c 100644 --- a/kernel/trace/trace_events_synth.c +++ b/kernel/trace/trace_events_synth.c @@ -420,12 +420,12 @@ static unsigned int trace_string(struct synth_trace_event *entry, data_offset += event->n_u64 * sizeof(u64); data_offset += data_size; - len = kern_fetch_store_strlen((unsigned long)str_val); + len = fetch_store_strlen((unsigned long)str_val); data_offset |= len << 16; *(u32 *)&entry->fields[*n_u64] = data_offset; - ret = kern_fetch_store_string((unsigned long)str_val, &entry->fields[*n_u64], entry); + ret = fetch_store_string((unsigned long)str_val, &entry->fields[*n_u64], entry); (*n_u64)++; } else { @@ -473,7 +473,7 @@ static notrace void trace_event_raw_event_synth(void *__data, val_idx = var_ref_idx[field_pos]; str_val = (char *)(long)var_ref_vals[val_idx]; - len = kern_fetch_store_strlen((unsigned long)str_val); + len = fetch_store_strlen((unsigned long)str_val); fields_size += len; } diff --git a/kernel/trace/trace_kprobe.c b/kernel/trace/trace_kprobe.c index 086e1e14f89e..d32c6244ef99 100644 --- a/kernel/trace/trace_kprobe.c +++ b/kernel/trace/trace_kprobe.c @@ -1218,60 +1218,6 @@ static const struct file_operations kprobe_profile_ops = { .release = seq_release, }; -/* Kprobe specific fetch functions */ - -/* Return the length of string -- including null terminal byte */ -static nokprobe_inline int -fetch_store_strlen_user(unsigned long addr) -{ - return kern_fetch_store_strlen_user(addr); -} - -/* Return the length of string -- including null terminal byte */ -static nokprobe_inline int -fetch_store_strlen(unsigned long addr) -{ - return kern_fetch_store_strlen(addr); -} - -/* - * Fetch a null-terminated string from user. Caller MUST set *(u32 *)buf - * with max length and relative data location. - */ -static nokprobe_inline int -fetch_store_string_user(unsigned long addr, void *dest, void *base) -{ - return kern_fetch_store_string_user(addr, dest, base); -} - -/* - * Fetch a null-terminated string. Caller MUST set *(u32 *)buf with max - * length and relative data location. - */ -static nokprobe_inline int -fetch_store_string(unsigned long addr, void *dest, void *base) -{ - return kern_fetch_store_string(addr, dest, base); -} - -static nokprobe_inline int -probe_mem_read_user(void *dest, void *src, size_t size) -{ - const void __user *uaddr = (__force const void __user *)src; - - return copy_from_user_nofault(dest, uaddr, size); -} - -static nokprobe_inline int -probe_mem_read(void *dest, void *src, size_t size) -{ -#ifdef CONFIG_ARCH_HAS_NON_OVERLAPPING_ADDRESS_SPACE - if ((unsigned long)src < TASK_SIZE) - return probe_mem_read_user(dest, src, size); -#endif - return copy_from_kernel_nofault(dest, src, size); -} - /* Note that we don't verify it, since the code does not come from user space */ static int process_fetch_insn(struct fetch_insn *code, void *rec, void *dest, diff --git a/kernel/trace/trace_probe_kernel.h b/kernel/trace/trace_probe_kernel.h index 77dbd9ff9782..c4e1d4c03a85 100644 --- a/kernel/trace/trace_probe_kernel.h +++ b/kernel/trace/trace_probe_kernel.h @@ -12,7 +12,7 @@ */ /* Return the length of string -- including null terminal byte */ static nokprobe_inline int -kern_fetch_store_strlen_user(unsigned long addr) +fetch_store_strlen_user(unsigned long addr) { const void __user *uaddr = (__force const void __user *)addr; int ret; @@ -29,14 +29,14 @@ kern_fetch_store_strlen_user(unsigned long addr) /* Return the length of string -- including null terminal byte */ static nokprobe_inline int -kern_fetch_store_strlen(unsigned long addr) +fetch_store_strlen(unsigned long addr) { int ret, len = 0; u8 c; #ifdef CONFIG_ARCH_HAS_NON_OVERLAPPING_ADDRESS_SPACE if (addr < TASK_SIZE) - return kern_fetch_store_strlen_user(addr); + return fetch_store_strlen_user(addr); #endif do { @@ -63,7 +63,7 @@ static nokprobe_inline void set_data_loc(int ret, void *dest, void *__dest, void * with max length and relative data location. */ static nokprobe_inline int -kern_fetch_store_string_user(unsigned long addr, void *dest, void *base) +fetch_store_string_user(unsigned long addr, void *dest, void *base) { const void __user *uaddr = (__force const void __user *)addr; int maxlen = get_loc_len(*(u32 *)dest); @@ -86,7 +86,7 @@ kern_fetch_store_string_user(unsigned long addr, void *dest, void *base) * length and relative data location. */ static nokprobe_inline int -kern_fetch_store_string(unsigned long addr, void *dest, void *base) +fetch_store_string(unsigned long addr, void *dest, void *base) { int maxlen = get_loc_len(*(u32 *)dest); void *__dest; @@ -94,7 +94,7 @@ kern_fetch_store_string(unsigned long addr, void *dest, void *base) #ifdef CONFIG_ARCH_HAS_NON_OVERLAPPING_ADDRESS_SPACE if ((unsigned long)addr < TASK_SIZE) - return kern_fetch_store_string_user(addr, dest, base); + return fetch_store_string_user(addr, dest, base); #endif if (unlikely(!maxlen)) @@ -112,4 +112,22 @@ kern_fetch_store_string(unsigned long addr, void *dest, void *base) return ret; } +static nokprobe_inline int +probe_mem_read_user(void *dest, void *src, size_t size) +{ + const void __user *uaddr = (__force const void __user *)src; + + return copy_from_user_nofault(dest, uaddr, size); +} + +static nokprobe_inline int +probe_mem_read(void *dest, void *src, size_t size) +{ +#ifdef CONFIG_ARCH_HAS_NON_OVERLAPPING_ADDRESS_SPACE + if ((unsigned long)src < TASK_SIZE) + return probe_mem_read_user(dest, src, size); +#endif + return copy_from_kernel_nofault(dest, src, size); +} + #endif /* __TRACE_PROBE_KERNEL_H_ */ -- cgit v1.2.3