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Subject[PATCH RFC V2] kernel/trace: move functions in trace_probe_tmpl.h to trace_probe.c
Date
I found there are simlilar implementation of functions like
process_fetch_insn, fetch_store* and probe_mem* respectively in
kprobe/uprobe/eprobe, they have a lot in common and their differences
can be merged. I have tried this idea in them and passed the selftest,
below is the report:

1, sudo ./ftracetest test.d/kprobe/
[sudo] kylin 的密码:
=== Ftrace unit tests ===
[1] Kprobe dynamic event - adding and removing [PASS]
......
[12] Kprobe dynamic event - probing module [UNRESOLVED]
......
[21] Uprobe event parser error log check [PASS]

2, sudo ./ftracetest test.d/dynevent/
=== Ftrace unit tests ===
[1] Generic dynamic event - add/remove eprobe events [PASS]
[2] Generic dynamic event - add/remove kprobe events [PASS]
......

You may have had the same idea at the first place, then turned to
put those functions in trace_probe_tmpl.h for the reason i'm not
aware of. Nevertheless, let me know if you like this idea.

---
v2:
1, bugfix:error: no member named 'utask' in 'struct task_struct'

Signed-off-by: Song Chen <chensong_2000@189.cn>
Reported-by: kernel test robot <lkp@intel.com>
---
kernel/trace/trace_eprobe.c | 194 +--------------
kernel/trace/trace_kprobe.c | 125 +---------
kernel/trace/trace_probe.c | 472 ++++++++++++++++++++++++++++++++++++
kernel/trace/trace_probe.h | 11 +
kernel/trace/trace_uprobe.c | 177 +-------------
5 files changed, 503 insertions(+), 476 deletions(-)

diff --git a/kernel/trace/trace_eprobe.c b/kernel/trace/trace_eprobe.c
index 5dd0617e5df6..e6de612aa4e0 100644
--- a/kernel/trace/trace_eprobe.c
+++ b/kernel/trace/trace_eprobe.c
@@ -15,8 +15,6 @@

#include "trace_dynevent.h"
#include "trace_probe.h"
-#include "trace_probe_tmpl.h"
-#include "trace_probe_kernel.h"

#define EPROBE_EVENT_SYSTEM "eprobes"

@@ -310,7 +308,7 @@ print_eprobe_event(struct trace_iterator *iter, int flags,

trace_seq_putc(s, ')');

- if (print_probe_args(s, tp->args, tp->nr_args,
+ if (trace_probe_print_args(s, tp->args, tp->nr_args,
(u8 *)&field[1], field) < 0)
goto out;

@@ -319,192 +317,6 @@ 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)
-{
- struct ftrace_event_field *field = code->data;
- unsigned long val;
- void *addr;
-
- addr = rec + field->offset;
-
- if (is_string_field(field)) {
- switch (field->filter_type) {
- case FILTER_DYN_STRING:
- val = (unsigned long)(rec + (*(unsigned int *)addr & 0xffff));
- break;
- case FILTER_RDYN_STRING:
- val = (unsigned long)(addr + (*(unsigned int *)addr & 0xffff));
- break;
- case FILTER_STATIC_STRING:
- val = (unsigned long)addr;
- break;
- case FILTER_PTR_STRING:
- val = (unsigned long)(*(char *)addr);
- break;
- default:
- WARN_ON_ONCE(1);
- return 0;
- }
- return val;
- }
-
- switch (field->size) {
- case 1:
- if (field->is_signed)
- val = *(char *)addr;
- else
- val = *(unsigned char *)addr;
- break;
- case 2:
- if (field->is_signed)
- val = *(short *)addr;
- else
- val = *(unsigned short *)addr;
- break;
- case 4:
- if (field->is_signed)
- val = *(int *)addr;
- else
- val = *(unsigned int *)addr;
- break;
- default:
- if (field->is_signed)
- val = *(long *)addr;
- else
- val = *(unsigned long *)addr;
- break;
- }
- return val;
-}
-
-static int get_eprobe_size(struct trace_probe *tp, void *rec)
-{
- struct fetch_insn *code;
- struct probe_arg *arg;
- int i, len, ret = 0;
-
- for (i = 0; i < tp->nr_args; i++) {
- arg = tp->args + i;
- if (arg->dynamic) {
- unsigned long val;
-
- code = arg->code;
- retry:
- switch (code->op) {
- case FETCH_OP_TP_ARG:
- val = get_event_field(code, rec);
- break;
- case FETCH_OP_IMM:
- val = code->immediate;
- break;
- case FETCH_OP_COMM:
- val = (unsigned long)current->comm;
- break;
- case FETCH_OP_DATA:
- val = (unsigned long)code->data;
- break;
- case FETCH_NOP_SYMBOL: /* Ignore a place holder */
- code++;
- goto retry;
- default:
- continue;
- }
- code++;
- len = process_fetch_insn_bottom(code, val, NULL, NULL);
- if (len > 0)
- ret += len;
- }
- }
-
- return ret;
-}
-
-/* Kprobe specific fetch functions */
-
-/* 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,
- void *base)
-{
- unsigned long val;
-
- retry:
- switch (code->op) {
- case FETCH_OP_TP_ARG:
- val = get_event_field(code, rec);
- break;
- case FETCH_OP_IMM:
- val = code->immediate;
- break;
- case FETCH_OP_COMM:
- val = (unsigned long)current->comm;
- break;
- case FETCH_OP_DATA:
- val = (unsigned long)code->data;
- break;
- case FETCH_NOP_SYMBOL: /* Ignore a place holder */
- code++;
- goto retry;
- default:
- return -EILSEQ;
- }
- code++;
- return process_fetch_insn_bottom(code, val, dest, base);
-}
-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)
@@ -520,7 +332,7 @@ __eprobe_trace_func(struct eprobe_data *edata, void *rec)
if (trace_trigger_soft_disabled(edata->file))
return;

- dsize = get_eprobe_size(&edata->ep->tp, rec);
+ dsize = trace_probe_get_data_size(&edata->ep->tp, rec);

entry = trace_event_buffer_reserve(&fbuffer, edata->file,
sizeof(*entry) + edata->ep->tp.size + dsize);
@@ -529,7 +341,7 @@ __eprobe_trace_func(struct eprobe_data *edata, void *rec)
return;

entry = fbuffer.entry = ring_buffer_event_data(fbuffer.event);
- store_trace_args(&entry[1], &edata->ep->tp, rec, sizeof(*entry), dsize);
+ trace_probe_store_args(&entry[1], &edata->ep->tp, rec, sizeof(*entry), dsize);

trace_event_buffer_commit(&fbuffer);
}
diff --git a/kernel/trace/trace_kprobe.c b/kernel/trace/trace_kprobe.c
index 5a75b039e586..d734602f2898 100644
--- a/kernel/trace/trace_kprobe.c
+++ b/kernel/trace/trace_kprobe.c
@@ -19,8 +19,6 @@
#include "trace_dynevent.h"
#include "trace_kprobe_selftest.h"
#include "trace_probe.h"
-#include "trace_probe_tmpl.h"
-#include "trace_probe_kernel.h"

#define KPROBE_EVENT_SYSTEM "kprobes"
#define KRETPROBE_MAXACTIVE_MAX 4096
@@ -1218,109 +1216,6 @@ 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,
- void *base)
-{
- struct pt_regs *regs = rec;
- unsigned long val;
-
-retry:
- /* 1st stage: get value from context */
- switch (code->op) {
- case FETCH_OP_REG:
- val = regs_get_register(regs, code->param);
- break;
- case FETCH_OP_STACK:
- val = regs_get_kernel_stack_nth(regs, code->param);
- break;
- case FETCH_OP_STACKP:
- val = kernel_stack_pointer(regs);
- break;
- case FETCH_OP_RETVAL:
- val = regs_return_value(regs);
- break;
- case FETCH_OP_IMM:
- val = code->immediate;
- break;
- case FETCH_OP_COMM:
- val = (unsigned long)current->comm;
- break;
- case FETCH_OP_DATA:
- val = (unsigned long)code->data;
- break;
-#ifdef CONFIG_HAVE_FUNCTION_ARG_ACCESS_API
- case FETCH_OP_ARG:
- val = regs_get_kernel_argument(regs, code->param);
- break;
-#endif
- case FETCH_NOP_SYMBOL: /* Ignore a place holder */
- code++;
- goto retry;
- default:
- return -EILSEQ;
- }
- code++;
-
- return process_fetch_insn_bottom(code, val, dest, base);
-}
-NOKPROBE_SYMBOL(process_fetch_insn)
-
/* Kprobe handler */
static nokprobe_inline void
__kprobe_trace_func(struct trace_kprobe *tk, struct pt_regs *regs,
@@ -1336,7 +1231,7 @@ __kprobe_trace_func(struct trace_kprobe *tk, struct pt_regs *regs,
if (trace_trigger_soft_disabled(trace_file))
return;

- dsize = __get_data_size(&tk->tp, regs);
+ dsize = trace_probe_get_data_size(&tk->tp, regs);

entry = trace_event_buffer_reserve(&fbuffer, trace_file,
sizeof(*entry) + tk->tp.size + dsize);
@@ -1346,7 +1241,7 @@ __kprobe_trace_func(struct trace_kprobe *tk, struct pt_regs *regs,
fbuffer.regs = regs;
entry = fbuffer.entry = ring_buffer_event_data(fbuffer.event);
entry->ip = (unsigned long)tk->rp.kp.addr;
- store_trace_args(&entry[1], &tk->tp, regs, sizeof(*entry), dsize);
+ trace_probe_store_args(&entry[1], &tk->tp, regs, sizeof(*entry), dsize);

trace_event_buffer_commit(&fbuffer);
}
@@ -1377,7 +1272,7 @@ __kretprobe_trace_func(struct trace_kprobe *tk, struct kretprobe_instance *ri,
if (trace_trigger_soft_disabled(trace_file))
return;

- dsize = __get_data_size(&tk->tp, regs);
+ dsize = trace_probe_get_data_size(&tk->tp, regs);

entry = trace_event_buffer_reserve(&fbuffer, trace_file,
sizeof(*entry) + tk->tp.size + dsize);
@@ -1388,7 +1283,7 @@ __kretprobe_trace_func(struct trace_kprobe *tk, struct kretprobe_instance *ri,
entry = fbuffer.entry = ring_buffer_event_data(fbuffer.event);
entry->func = (unsigned long)tk->rp.kp.addr;
entry->ret_ip = get_kretprobe_retaddr(ri);
- store_trace_args(&entry[1], &tk->tp, regs, sizeof(*entry), dsize);
+ trace_probe_store_args(&entry[1], &tk->tp, regs, sizeof(*entry), dsize);

trace_event_buffer_commit(&fbuffer);
}
@@ -1426,7 +1321,7 @@ print_kprobe_event(struct trace_iterator *iter, int flags,

trace_seq_putc(s, ')');

- if (print_probe_args(s, tp->args, tp->nr_args,
+ if (trace_probe_print_args(s, tp->args, tp->nr_args,
(u8 *)&field[1], field) < 0)
goto out;

@@ -1461,7 +1356,7 @@ print_kretprobe_event(struct trace_iterator *iter, int flags,

trace_seq_putc(s, ')');

- if (print_probe_args(s, tp->args, tp->nr_args,
+ if (trace_probe_print_args(s, tp->args, tp->nr_args,
(u8 *)&field[1], field) < 0)
goto out;

@@ -1536,7 +1431,7 @@ kprobe_perf_func(struct trace_kprobe *tk, struct pt_regs *regs)
if (hlist_empty(head))
return 0;

- dsize = __get_data_size(&tk->tp, regs);
+ dsize = trace_probe_get_data_size(&tk->tp, regs);
__size = sizeof(*entry) + tk->tp.size + dsize;
size = ALIGN(__size + sizeof(u32), sizeof(u64));
size -= sizeof(u32);
@@ -1547,7 +1442,7 @@ kprobe_perf_func(struct trace_kprobe *tk, struct pt_regs *regs)

entry->ip = (unsigned long)tk->rp.kp.addr;
memset(&entry[1], 0, dsize);
- store_trace_args(&entry[1], &tk->tp, regs, sizeof(*entry), dsize);
+ trace_probe_store_args(&entry[1], &tk->tp, regs, sizeof(*entry), dsize);
perf_trace_buf_submit(entry, size, rctx, call->event.type, 1, regs,
head, NULL);
return 0;
@@ -1572,7 +1467,7 @@ kretprobe_perf_func(struct trace_kprobe *tk, struct kretprobe_instance *ri,
if (hlist_empty(head))
return;

- dsize = __get_data_size(&tk->tp, regs);
+ dsize = trace_probe_get_data_size(&tk->tp, regs);
__size = sizeof(*entry) + tk->tp.size + dsize;
size = ALIGN(__size + sizeof(u32), sizeof(u64));
size -= sizeof(u32);
@@ -1583,7 +1478,7 @@ kretprobe_perf_func(struct trace_kprobe *tk, struct kretprobe_instance *ri,

entry->func = (unsigned long)tk->rp.kp.addr;
entry->ret_ip = get_kretprobe_retaddr(ri);
- store_trace_args(&entry[1], &tk->tp, regs, sizeof(*entry), dsize);
+ trace_probe_store_args(&entry[1], &tk->tp, regs, sizeof(*entry), dsize);
perf_trace_buf_submit(entry, size, rctx, call->event.type, 1, regs,
head, NULL);
}
diff --git a/kernel/trace/trace_probe.c b/kernel/trace/trace_probe.c
index 36dff277de46..b2aa1f08ee3a 100644
--- a/kernel/trace/trace_probe.c
+++ b/kernel/trace/trace_probe.c
@@ -12,6 +12,7 @@
#define pr_fmt(fmt) "trace_probe: " fmt

#include "trace_probe.h"
+#include "trace_probe_kernel.h"

#undef C
#define C(a, b) b
@@ -1218,3 +1219,474 @@ int trace_probe_create(const char *raw_command, int (*createfn)(int, const char

return ret;
}
+
+/*
+ * Fetch a null-terminated string. Caller MUST set *(u32 *)dest with max
+ * length and relative data location.
+ */
+static nokprobe_inline int
+user_fetch_store_string(unsigned long addr, void *dest, void *base)
+{
+ long ret;
+ u32 loc = *(u32 *)dest;
+ int maxlen = get_loc_len(loc);
+ u8 *dst = get_loc_data(dest, base);
+ void __user *src = (void __force __user *) addr;
+
+ if (unlikely(!maxlen))
+ return -ENOMEM;
+
+ if (addr == FETCH_TOKEN_COMM)
+ ret = strlcpy(dst, current->comm, maxlen);
+ else
+ ret = strncpy_from_user(dst, src, maxlen);
+ if (ret >= 0) {
+ if (ret == maxlen)
+ dst[ret - 1] = '\0';
+ else
+ /*
+ * Include the terminating null byte. In this case it
+ * was copied by strncpy_from_user but not accounted
+ * for in ret.
+ */
+ ret++;
+ *(u32 *)dest = make_data_loc(ret, (void *)dst - base);
+ }
+
+ return ret;
+}
+
+static nokprobe_inline int
+user_fetch_store_string_user(unsigned long addr, void *dest, void *base)
+{
+ return user_fetch_store_string(addr, dest, base);
+}
+
+/* Return the length of string -- including null terminal byte */
+static nokprobe_inline int
+user_fetch_store_strlen(unsigned long addr)
+{
+ int len;
+ void __user *vaddr = (void __force __user *) addr;
+
+ if (addr == FETCH_TOKEN_COMM)
+ len = strlen(current->comm) + 1;
+ else
+ len = strnlen_user(vaddr, MAX_STRING_SIZE);
+
+ return (len > MAX_STRING_SIZE) ? 0 : len;
+}
+
+static nokprobe_inline int
+user_fetch_store_strlen_user(unsigned long addr)
+{
+ return user_fetch_store_strlen(addr);
+}
+
+static nokprobe_inline void
+fetch_store_raw(unsigned long val, struct fetch_insn *code, void *buf)
+{
+ switch (code->size) {
+ case 1:
+ *(u8 *)buf = (u8)val;
+ break;
+ case 2:
+ *(u16 *)buf = (u16)val;
+ break;
+ case 4:
+ *(u32 *)buf = (u32)val;
+ break;
+ case 8:
+ //TBD: 32bit signed
+ *(u64 *)buf = (u64)val;
+ break;
+ default:
+ *(unsigned long *)buf = val;
+ }
+}
+
+static nokprobe_inline void
+fetch_apply_bitfield(struct fetch_insn *code, void *buf)
+{
+ switch (code->basesize) {
+ case 1:
+ *(u8 *)buf <<= code->lshift;
+ *(u8 *)buf >>= code->rshift;
+ break;
+ case 2:
+ *(u16 *)buf <<= code->lshift;
+ *(u16 *)buf >>= code->rshift;
+ break;
+ case 4:
+ *(u32 *)buf <<= code->lshift;
+ *(u32 *)buf >>= code->rshift;
+ break;
+ case 8:
+ *(u64 *)buf <<= code->lshift;
+ *(u64 *)buf >>= code->rshift;
+ break;
+ }
+}
+
+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);
+}
+
+/* From the 2nd stage, routine is same */
+static nokprobe_inline int
+process_fetch_insn_bottom(struct fetch_insn *code, unsigned long val,
+ void *dest, void *base, int flags)
+{
+ struct fetch_insn *s3 = NULL;
+ int total = 0, ret = 0, i = 0;
+ u32 loc = 0;
+ unsigned long lval = val;
+ int is_uprobe = flags & TRACE_EVENT_FL_UPROBE;
+
+stage2:
+ /* 2nd stage: dereference memory if needed */
+ do {
+ if (code->op == FETCH_OP_DEREF) {
+ lval = val;
+ ret = probe_mem_read(&val, (void *)val + code->offset,
+ sizeof(val));
+ } else if (code->op == FETCH_OP_UDEREF) {
+ lval = val;
+ ret = probe_mem_read_user(&val,
+ (void *)val + code->offset, sizeof(val));
+ } else
+ break;
+ if (ret)
+ return ret;
+ code++;
+ } while (1);
+
+ s3 = code;
+stage3:
+ /* 3rd stage: store value to buffer */
+ if (unlikely(!dest)) {
+ if (code->op == FETCH_OP_ST_STRING) {
+ if (is_uprobe)
+ ret = user_fetch_store_strlen(val + code->offset);
+ else
+ ret = kern_fetch_store_strlen(val + code->offset);
+ code++;
+ goto array;
+ } else if (code->op == FETCH_OP_ST_USTRING) {
+ if (is_uprobe)
+ ret += user_fetch_store_strlen_user(val + code->offset);
+ else
+ ret += kern_fetch_store_strlen_user(val + code->offset);
+ code++;
+ goto array;
+ } else
+ return -EILSEQ;
+ }
+
+ switch (code->op) {
+ case FETCH_OP_ST_RAW:
+ fetch_store_raw(val, code, dest);
+ break;
+ case FETCH_OP_ST_MEM:
+ probe_mem_read(dest, (void *)val + code->offset, code->size);
+ break;
+ case FETCH_OP_ST_UMEM:
+ probe_mem_read_user(dest, (void *)val + code->offset, code->size);
+ break;
+ case FETCH_OP_ST_STRING:
+ loc = *(u32 *)dest;
+ if (is_uprobe)
+ ret = user_fetch_store_string(val + code->offset, dest, base);
+ else
+ ret = kern_fetch_store_string(val + code->offset, dest, base);
+ break;
+ case FETCH_OP_ST_USTRING:
+ loc = *(u32 *)dest;
+ if (is_uprobe)
+ ret = user_fetch_store_string_user(val + code->offset, dest, base);
+ else
+ ret = kern_fetch_store_string_user(val + code->offset, dest, base);
+ break;
+ default:
+ return -EILSEQ;
+ }
+ code++;
+
+ /* 4th stage: modify stored value if needed */
+ if (code->op == FETCH_OP_MOD_BF) {
+ fetch_apply_bitfield(code, dest);
+ code++;
+ }
+
+array:
+ /* the last stage: Loop on array */
+ if (code->op == FETCH_OP_LP_ARRAY) {
+ total += ret;
+ if (++i < code->param) {
+ code = s3;
+ if (s3->op != FETCH_OP_ST_STRING &&
+ s3->op != FETCH_OP_ST_USTRING) {
+ dest += s3->size;
+ val += s3->size;
+ goto stage3;
+ }
+ code--;
+ val = lval + sizeof(char *);
+ if (dest) {
+ dest += sizeof(u32);
+ *(u32 *)dest = update_data_loc(loc, ret);
+ }
+ goto stage2;
+ }
+ code++;
+ ret = total;
+ }
+
+ return code->op == FETCH_OP_END ? ret : -EILSEQ;
+}
+
+static unsigned long get_event_field(struct fetch_insn *code, void *rec)
+{
+ struct ftrace_event_field *field = code->data;
+ unsigned long val;
+ void *addr;
+
+ addr = rec + field->offset;
+
+ if (is_string_field(field)) {
+ switch (field->filter_type) {
+ case FILTER_DYN_STRING:
+ val = (unsigned long)(rec + (*(unsigned int *)addr & 0xffff));
+ break;
+ case FILTER_RDYN_STRING:
+ val = (unsigned long)(addr + (*(unsigned int *)addr & 0xffff));
+ break;
+ case FILTER_STATIC_STRING:
+ val = (unsigned long)addr;
+ break;
+ case FILTER_PTR_STRING:
+ val = (unsigned long)(*(char *)addr);
+ break;
+ default:
+ WARN_ON_ONCE(1);
+ return 0;
+ }
+ return val;
+ }
+
+ switch (field->size) {
+ case 1:
+ if (field->is_signed)
+ val = *(char *)addr;
+ else
+ val = *(unsigned char *)addr;
+ break;
+ case 2:
+ if (field->is_signed)
+ val = *(short *)addr;
+ else
+ val = *(unsigned short *)addr;
+ break;
+ case 4:
+ if (field->is_signed)
+ val = *(int *)addr;
+ else
+ val = *(unsigned int *)addr;
+ break;
+ default:
+ if (field->is_signed)
+ val = *(long *)addr;
+ else
+ val = *(unsigned long *)addr;
+ break;
+ }
+ return val;
+}
+
+#ifdef CONFIG_STACK_GROWSUP
+static unsigned long adjust_stack_addr(unsigned long addr, unsigned int n)
+{
+ return addr - (n * sizeof(long));
+}
+#else
+static unsigned long adjust_stack_addr(unsigned long addr, unsigned int n)
+{
+ return addr + (n * sizeof(long));
+}
+#endif
+
+static unsigned long get_user_stack_nth(struct pt_regs *regs, unsigned int n)
+{
+ unsigned long ret;
+ unsigned long addr = user_stack_pointer(regs);
+
+ addr = adjust_stack_addr(addr, n);
+
+ if (copy_from_user(&ret, (void __force __user *) addr, sizeof(ret)))
+ return 0;
+
+ return ret;
+}
+
+#ifdef CONFIG_UPROBES
+static unsigned long translate_user_vaddr(unsigned long file_offset)
+{
+ unsigned long base_addr;
+ struct uprobe_dispatch_data *udd;
+
+ udd = (void *) current->utask->vaddr;
+
+ base_addr = udd->bp_addr - udd->offset;
+ return base_addr + file_offset;
+}
+#endif
+
+/* 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,
+ void *base, int flags)
+{
+ struct pt_regs *regs = rec;
+ unsigned long val;
+ int is_uprobe = flags & TRACE_EVENT_FL_UPROBE;
+
+retry:
+ /* 1st stage: get value from context */
+ switch (code->op) {
+ case FETCH_OP_REG:
+ val = regs_get_register(regs, code->param);
+ break;
+ case FETCH_OP_STACK:
+ if (is_uprobe)
+ val = get_user_stack_nth(regs, code->param);
+ else
+ val = regs_get_kernel_stack_nth(regs, code->param);
+ break;
+ case FETCH_OP_STACKP:
+ if (is_uprobe)
+ val = user_stack_pointer(regs);
+ else
+ val = kernel_stack_pointer(regs);
+ break;
+ case FETCH_OP_RETVAL:
+ val = regs_return_value(regs);
+ break;
+ case FETCH_OP_IMM:
+ val = code->immediate;
+ break;
+ case FETCH_OP_COMM:
+ val = (unsigned long)current->comm;
+ break;
+ case FETCH_OP_DATA:
+ val = (unsigned long)code->data;
+ break;
+#ifdef CONFIG_HAVE_FUNCTION_ARG_ACCESS_API
+ case FETCH_OP_ARG:
+ val = regs_get_kernel_argument(regs, code->param);
+ break;
+#endif
+ case FETCH_NOP_SYMBOL: /* Ignore a place holder */
+ code++;
+ goto retry;
+ case FETCH_OP_TP_ARG:
+ val = get_event_field(code, rec);
+ break;
+#ifdef CONFIG_UPROBES
+ case FETCH_OP_FOFFS:
+ val = translate_user_vaddr(code->immediate);
+ break;
+#endif
+ default:
+ return -EILSEQ;
+ }
+ code++;
+
+ return process_fetch_insn_bottom(code, val, dest, base, flags);
+}
+NOKPROBE_SYMBOL(process_fetch_insn)
+
+/* Sum up total data length for dynamic arrays (strings) */
+int trace_probe_get_data_size(struct trace_probe *tp, struct pt_regs *regs)
+{
+ struct probe_arg *arg;
+ int i, len, ret = 0;
+ struct trace_event_call *call = trace_probe_event_call(tp);
+
+ for (i = 0; i < tp->nr_args; i++) {
+ arg = tp->args + i;
+ if (unlikely(arg->dynamic)) {
+ len = process_fetch_insn(arg->code, regs, NULL, NULL, call->flags);
+ if (len > 0)
+ ret += len;
+ }
+ }
+
+ return ret;
+}
+
+void trace_probe_store_args(void *data, struct trace_probe *tp, void *rec,
+ int header_size, int maxlen)
+{
+ struct probe_arg *arg;
+ void *base = data - header_size;
+ void *dyndata = data + tp->size;
+ u32 *dl; /* Data location */
+ int ret, i;
+ struct trace_event_call *call = trace_probe_event_call(tp);
+
+ for (i = 0; i < tp->nr_args; i++) {
+ arg = tp->args + i;
+ dl = data + arg->offset;
+ /* Point the dynamic data area if needed */
+ if (unlikely(arg->dynamic))
+ *dl = make_data_loc(maxlen, dyndata - base);
+ ret = process_fetch_insn(arg->code, rec, dl, base, call->flags);
+ if (unlikely(ret < 0 && arg->dynamic)) {
+ *dl = make_data_loc(0, dyndata - base);
+ } else {
+ dyndata += ret;
+ maxlen -= ret;
+ }
+ }
+}
+
+int trace_probe_print_args(struct trace_seq *s, struct probe_arg *args, int nr_args,
+ u8 *data, void *field)
+{
+ void *p;
+ int i, j;
+
+ for (i = 0; i < nr_args; i++) {
+ struct probe_arg *a = args + i;
+
+ trace_seq_printf(s, " %s=", a->name);
+ if (likely(!a->count)) {
+ if (!a->type->print(s, data + a->offset, field))
+ return -ENOMEM;
+ continue;
+ }
+ trace_seq_putc(s, '{');
+ p = data + a->offset;
+ for (j = 0; j < a->count; j++) {
+ if (!a->type->print(s, p, field))
+ return -ENOMEM;
+ trace_seq_putc(s, j == a->count - 1 ? '}' : ',');
+ p += a->type->size;
+ }
+ }
+ return 0;
+}
diff --git a/kernel/trace/trace_probe.h b/kernel/trace/trace_probe.h
index de38f1c03776..918466087583 100644
--- a/kernel/trace/trace_probe.h
+++ b/kernel/trace/trace_probe.h
@@ -223,6 +223,12 @@ struct probe_arg {
const struct fetch_type *type; /* Type of this argument */
};

+struct uprobe_dispatch_data {
+ struct trace_uprobe *tu;
+ unsigned long bp_addr;
+ unsigned long offset;
+};
+
struct trace_uprobe_filter {
rwlock_t rwlock;
int nr_systemwide;
@@ -343,6 +349,11 @@ int trace_probe_compare_arg_type(struct trace_probe *a, struct trace_probe *b);
bool trace_probe_match_command_args(struct trace_probe *tp,
int argc, const char **argv);
int trace_probe_create(const char *raw_command, int (*createfn)(int, const char **));
+int trace_probe_get_data_size(struct trace_probe *tp, struct pt_regs *regs);
+void trace_probe_store_args(void *data, struct trace_probe *tp, void *rec,
+ int header_size, int maxlen);
+int trace_probe_print_args(struct trace_seq *s, struct probe_arg *args, int nr_args,
+ u8 *data, void *field);

#define trace_probe_for_each_link(pos, tp) \
list_for_each_entry(pos, &(tp)->event->files, list)
diff --git a/kernel/trace/trace_uprobe.c b/kernel/trace/trace_uprobe.c
index fb58e86dd117..abce09295f05 100644
--- a/kernel/trace/trace_uprobe.c
+++ b/kernel/trace/trace_uprobe.c
@@ -20,7 +20,6 @@

#include "trace_dynevent.h"
#include "trace_probe.h"
-#include "trace_probe_tmpl.h"

#define UPROBE_EVENT_SYSTEM "uprobes"

@@ -88,174 +87,10 @@ static struct trace_uprobe *to_trace_uprobe(struct dyn_event *ev)
static int register_uprobe_event(struct trace_uprobe *tu);
static int unregister_uprobe_event(struct trace_uprobe *tu);

-struct uprobe_dispatch_data {
- struct trace_uprobe *tu;
- unsigned long bp_addr;
-};
-
static int uprobe_dispatcher(struct uprobe_consumer *con, struct pt_regs *regs);
static int uretprobe_dispatcher(struct uprobe_consumer *con,
unsigned long func, struct pt_regs *regs);

-#ifdef CONFIG_STACK_GROWSUP
-static unsigned long adjust_stack_addr(unsigned long addr, unsigned int n)
-{
- return addr - (n * sizeof(long));
-}
-#else
-static unsigned long adjust_stack_addr(unsigned long addr, unsigned int n)
-{
- return addr + (n * sizeof(long));
-}
-#endif
-
-static unsigned long get_user_stack_nth(struct pt_regs *regs, unsigned int n)
-{
- unsigned long ret;
- unsigned long addr = user_stack_pointer(regs);
-
- addr = adjust_stack_addr(addr, n);
-
- if (copy_from_user(&ret, (void __force __user *) addr, sizeof(ret)))
- return 0;
-
- return ret;
-}
-
-/*
- * Uprobes-specific fetch functions
- */
-static nokprobe_inline int
-probe_mem_read(void *dest, void *src, size_t size)
-{
- void __user *vaddr = (void __force __user *)src;
-
- return copy_from_user(dest, vaddr, size) ? -EFAULT : 0;
-}
-
-static nokprobe_inline int
-probe_mem_read_user(void *dest, void *src, size_t size)
-{
- return probe_mem_read(dest, src, size);
-}
-
-/*
- * Fetch a null-terminated string. Caller MUST set *(u32 *)dest with max
- * length and relative data location.
- */
-static nokprobe_inline int
-fetch_store_string(unsigned long addr, void *dest, void *base)
-{
- long ret;
- u32 loc = *(u32 *)dest;
- int maxlen = get_loc_len(loc);
- u8 *dst = get_loc_data(dest, base);
- void __user *src = (void __force __user *) addr;
-
- if (unlikely(!maxlen))
- return -ENOMEM;
-
- if (addr == FETCH_TOKEN_COMM)
- ret = strlcpy(dst, current->comm, maxlen);
- else
- ret = strncpy_from_user(dst, src, maxlen);
- if (ret >= 0) {
- if (ret == maxlen)
- dst[ret - 1] = '\0';
- else
- /*
- * Include the terminating null byte. In this case it
- * was copied by strncpy_from_user but not accounted
- * for in ret.
- */
- ret++;
- *(u32 *)dest = make_data_loc(ret, (void *)dst - base);
- }
-
- return ret;
-}
-
-static nokprobe_inline int
-fetch_store_string_user(unsigned long addr, void *dest, void *base)
-{
- return fetch_store_string(addr, dest, base);
-}
-
-/* Return the length of string -- including null terminal byte */
-static nokprobe_inline int
-fetch_store_strlen(unsigned long addr)
-{
- int len;
- void __user *vaddr = (void __force __user *) addr;
-
- if (addr == FETCH_TOKEN_COMM)
- len = strlen(current->comm) + 1;
- else
- len = strnlen_user(vaddr, MAX_STRING_SIZE);
-
- return (len > MAX_STRING_SIZE) ? 0 : len;
-}
-
-static nokprobe_inline int
-fetch_store_strlen_user(unsigned long addr)
-{
- return fetch_store_strlen(addr);
-}
-
-static unsigned long translate_user_vaddr(unsigned long file_offset)
-{
- unsigned long base_addr;
- struct uprobe_dispatch_data *udd;
-
- udd = (void *) current->utask->vaddr;
-
- base_addr = udd->bp_addr - udd->tu->offset;
- return base_addr + file_offset;
-}
-
-/* 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,
- void *base)
-{
- struct pt_regs *regs = rec;
- unsigned long val;
-
- /* 1st stage: get value from context */
- switch (code->op) {
- case FETCH_OP_REG:
- val = regs_get_register(regs, code->param);
- break;
- case FETCH_OP_STACK:
- val = get_user_stack_nth(regs, code->param);
- break;
- case FETCH_OP_STACKP:
- val = user_stack_pointer(regs);
- break;
- case FETCH_OP_RETVAL:
- val = regs_return_value(regs);
- break;
- case FETCH_OP_IMM:
- val = code->immediate;
- break;
- case FETCH_OP_COMM:
- val = FETCH_TOKEN_COMM;
- break;
- case FETCH_OP_DATA:
- val = (unsigned long)code->data;
- break;
- case FETCH_OP_FOFFS:
- val = translate_user_vaddr(code->immediate);
- break;
- default:
- return -EILSEQ;
- }
- code++;
-
- return process_fetch_insn_bottom(code, val, dest, base);
-}
-NOKPROBE_SYMBOL(process_fetch_insn)
-
static inline void init_trace_uprobe_filter(struct trace_uprobe_filter *filter)
{
rwlock_init(&filter->rwlock);
@@ -1041,7 +876,7 @@ print_uprobe_event(struct trace_iterator *iter, int flags, struct trace_event *e
data = DATAOF_TRACE_ENTRY(entry, false);
}

- if (print_probe_args(s, tu->tp.args, tu->tp.nr_args, data, entry) < 0)
+ if (trace_probe_print_args(s, tu->tp.args, tu->tp.nr_args, data, entry) < 0)
goto out;

trace_seq_putc(s, '\n');
@@ -1485,6 +1320,7 @@ static int uprobe_dispatcher(struct uprobe_consumer *con, struct pt_regs *regs)
tu->nhit++;

udd.tu = tu;
+ udd.offset = tu->offset;
udd.bp_addr = instruction_pointer(regs);

current->utask->vaddr = (unsigned long) &udd;
@@ -1492,11 +1328,11 @@ static int uprobe_dispatcher(struct uprobe_consumer *con, struct pt_regs *regs)
if (WARN_ON_ONCE(!uprobe_cpu_buffer))
return 0;

- dsize = __get_data_size(&tu->tp, regs);
+ dsize = trace_probe_get_data_size(&tu->tp, regs);
esize = SIZEOF_TRACE_ENTRY(is_ret_probe(tu));

ucb = uprobe_buffer_get();
- store_trace_args(ucb->buf, &tu->tp, regs, esize, dsize);
+ trace_probe_store_args(ucb->buf, &tu->tp, regs, esize, dsize);

if (trace_probe_test_flag(&tu->tp, TP_FLAG_TRACE))
ret |= uprobe_trace_func(tu, regs, ucb, dsize);
@@ -1520,6 +1356,7 @@ static int uretprobe_dispatcher(struct uprobe_consumer *con,
tu = container_of(con, struct trace_uprobe, consumer);

udd.tu = tu;
+ udd.offset = tu->offset;
udd.bp_addr = func;

current->utask->vaddr = (unsigned long) &udd;
@@ -1527,11 +1364,11 @@ static int uretprobe_dispatcher(struct uprobe_consumer *con,
if (WARN_ON_ONCE(!uprobe_cpu_buffer))
return 0;

- dsize = __get_data_size(&tu->tp, regs);
+ dsize = trace_probe_get_data_size(&tu->tp, regs);
esize = SIZEOF_TRACE_ENTRY(is_ret_probe(tu));

ucb = uprobe_buffer_get();
- store_trace_args(ucb->buf, &tu->tp, regs, esize, dsize);
+ trace_probe_store_args(ucb->buf, &tu->tp, regs, esize, dsize);

if (trace_probe_test_flag(&tu->tp, TP_FLAG_TRACE))
uretprobe_trace_func(tu, func, regs, ucb, dsize);
--
2.25.1
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