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Diffstat (limited to 'kernel/trace/bpf_trace.c')
-rw-r--r--kernel/trace/bpf_trace.c162
1 files changed, 99 insertions, 63 deletions
diff --git a/kernel/trace/bpf_trace.c b/kernel/trace/bpf_trace.c
index 3744372a24e2..e729c9e587a0 100644
--- a/kernel/trace/bpf_trace.c
+++ b/kernel/trace/bpf_trace.c
@@ -136,17 +136,23 @@ static const struct bpf_func_proto bpf_override_return_proto = {
};
#endif
-BPF_CALL_3(bpf_probe_read_user, void *, dst, u32, size,
- const void __user *, unsafe_ptr)
+static __always_inline int
+bpf_probe_read_user_common(void *dst, u32 size, const void __user *unsafe_ptr)
{
- int ret = probe_user_read(dst, unsafe_ptr, size);
+ int ret;
+ ret = probe_user_read(dst, unsafe_ptr, size);
if (unlikely(ret < 0))
memset(dst, 0, size);
-
return ret;
}
+BPF_CALL_3(bpf_probe_read_user, void *, dst, u32, size,
+ const void __user *, unsafe_ptr)
+{
+ return bpf_probe_read_user_common(dst, size, unsafe_ptr);
+}
+
const struct bpf_func_proto bpf_probe_read_user_proto = {
.func = bpf_probe_read_user,
.gpl_only = true,
@@ -156,17 +162,24 @@ const struct bpf_func_proto bpf_probe_read_user_proto = {
.arg3_type = ARG_ANYTHING,
};
-BPF_CALL_3(bpf_probe_read_user_str, void *, dst, u32, size,
- const void __user *, unsafe_ptr)
+static __always_inline int
+bpf_probe_read_user_str_common(void *dst, u32 size,
+ const void __user *unsafe_ptr)
{
- int ret = strncpy_from_unsafe_user(dst, unsafe_ptr, size);
+ int ret;
+ ret = strncpy_from_user_nofault(dst, unsafe_ptr, size);
if (unlikely(ret < 0))
memset(dst, 0, size);
-
return ret;
}
+BPF_CALL_3(bpf_probe_read_user_str, void *, dst, u32, size,
+ const void __user *, unsafe_ptr)
+{
+ return bpf_probe_read_user_str_common(dst, size, unsafe_ptr);
+}
+
const struct bpf_func_proto bpf_probe_read_user_str_proto = {
.func = bpf_probe_read_user_str,
.gpl_only = true,
@@ -177,25 +190,25 @@ const struct bpf_func_proto bpf_probe_read_user_str_proto = {
};
static __always_inline int
-bpf_probe_read_kernel_common(void *dst, u32 size, const void *unsafe_ptr,
- const bool compat)
+bpf_probe_read_kernel_common(void *dst, u32 size, const void *unsafe_ptr)
{
int ret = security_locked_down(LOCKDOWN_BPF_READ);
if (unlikely(ret < 0))
- goto out;
- ret = compat ? probe_kernel_read(dst, unsafe_ptr, size) :
- probe_kernel_read_strict(dst, unsafe_ptr, size);
+ goto fail;
+ ret = probe_kernel_read(dst, unsafe_ptr, size);
if (unlikely(ret < 0))
-out:
- memset(dst, 0, size);
+ goto fail;
+ return ret;
+fail:
+ memset(dst, 0, size);
return ret;
}
BPF_CALL_3(bpf_probe_read_kernel, void *, dst, u32, size,
const void *, unsafe_ptr)
{
- return bpf_probe_read_kernel_common(dst, size, unsafe_ptr, false);
+ return bpf_probe_read_kernel_common(dst, size, unsafe_ptr);
}
const struct bpf_func_proto bpf_probe_read_kernel_proto = {
@@ -207,50 +220,37 @@ const struct bpf_func_proto bpf_probe_read_kernel_proto = {
.arg3_type = ARG_ANYTHING,
};
-BPF_CALL_3(bpf_probe_read_compat, void *, dst, u32, size,
- const void *, unsafe_ptr)
-{
- return bpf_probe_read_kernel_common(dst, size, unsafe_ptr, true);
-}
-
-static const struct bpf_func_proto bpf_probe_read_compat_proto = {
- .func = bpf_probe_read_compat,
- .gpl_only = true,
- .ret_type = RET_INTEGER,
- .arg1_type = ARG_PTR_TO_UNINIT_MEM,
- .arg2_type = ARG_CONST_SIZE_OR_ZERO,
- .arg3_type = ARG_ANYTHING,
-};
-
static __always_inline int
-bpf_probe_read_kernel_str_common(void *dst, u32 size, const void *unsafe_ptr,
- const bool compat)
+bpf_probe_read_kernel_str_common(void *dst, u32 size, const void *unsafe_ptr)
{
int ret = security_locked_down(LOCKDOWN_BPF_READ);
if (unlikely(ret < 0))
- goto out;
+ goto fail;
+
/*
- * The strncpy_from_unsafe_*() call will likely not fill the entire
- * buffer, but that's okay in this circumstance as we're probing
+ * The strncpy_from_kernel_nofault() call will likely not fill the
+ * entire buffer, but that's okay in this circumstance as we're probing
* arbitrary memory anyway similar to bpf_probe_read_*() and might
* as well probe the stack. Thus, memory is explicitly cleared
* only in error case, so that improper users ignoring return
* code altogether don't copy garbage; otherwise length of string
* is returned that can be used for bpf_perf_event_output() et al.
*/
- ret = compat ? strncpy_from_unsafe(dst, unsafe_ptr, size) :
- strncpy_from_unsafe_strict(dst, unsafe_ptr, size);
+ ret = strncpy_from_kernel_nofault(dst, unsafe_ptr, size);
if (unlikely(ret < 0))
-out:
- memset(dst, 0, size);
+ goto fail;
+
+ return 0;
+fail:
+ memset(dst, 0, size);
return ret;
}
BPF_CALL_3(bpf_probe_read_kernel_str, void *, dst, u32, size,
const void *, unsafe_ptr)
{
- return bpf_probe_read_kernel_str_common(dst, size, unsafe_ptr, false);
+ return bpf_probe_read_kernel_str_common(dst, size, unsafe_ptr);
}
const struct bpf_func_proto bpf_probe_read_kernel_str_proto = {
@@ -262,10 +262,34 @@ const struct bpf_func_proto bpf_probe_read_kernel_str_proto = {
.arg3_type = ARG_ANYTHING,
};
+#ifdef CONFIG_ARCH_HAS_NON_OVERLAPPING_ADDRESS_SPACE
+BPF_CALL_3(bpf_probe_read_compat, void *, dst, u32, size,
+ const void *, unsafe_ptr)
+{
+ if ((unsigned long)unsafe_ptr < TASK_SIZE) {
+ return bpf_probe_read_user_common(dst, size,
+ (__force void __user *)unsafe_ptr);
+ }
+ return bpf_probe_read_kernel_common(dst, size, unsafe_ptr);
+}
+
+static const struct bpf_func_proto bpf_probe_read_compat_proto = {
+ .func = bpf_probe_read_compat,
+ .gpl_only = true,
+ .ret_type = RET_INTEGER,
+ .arg1_type = ARG_PTR_TO_UNINIT_MEM,
+ .arg2_type = ARG_CONST_SIZE_OR_ZERO,
+ .arg3_type = ARG_ANYTHING,
+};
+
BPF_CALL_3(bpf_probe_read_compat_str, void *, dst, u32, size,
const void *, unsafe_ptr)
{
- return bpf_probe_read_kernel_str_common(dst, size, unsafe_ptr, true);
+ if ((unsigned long)unsafe_ptr < TASK_SIZE) {
+ return bpf_probe_read_user_str_common(dst, size,
+ (__force void __user *)unsafe_ptr);
+ }
+ return bpf_probe_read_kernel_str_common(dst, size, unsafe_ptr);
}
static const struct bpf_func_proto bpf_probe_read_compat_str_proto = {
@@ -276,6 +300,7 @@ static const struct bpf_func_proto bpf_probe_read_compat_str_proto = {
.arg2_type = ARG_CONST_SIZE_OR_ZERO,
.arg3_type = ARG_ANYTHING,
};
+#endif /* CONFIG_ARCH_HAS_NON_OVERLAPPING_ADDRESS_SPACE */
BPF_CALL_3(bpf_probe_write_user, void __user *, unsafe_ptr, const void *, src,
u32, size)
@@ -324,6 +349,31 @@ static const struct bpf_func_proto *bpf_get_probe_write_proto(void)
return &bpf_probe_write_user_proto;
}
+static void bpf_trace_copy_string(char *buf, void *unsafe_ptr, char fmt_ptype,
+ size_t bufsz)
+{
+ void __user *user_ptr = (__force void __user *)unsafe_ptr;
+
+ buf[0] = 0;
+
+ switch (fmt_ptype) {
+ case 's':
+#ifdef CONFIG_ARCH_HAS_NON_OVERLAPPING_ADDRESS_SPACE
+ if ((unsigned long)unsafe_ptr < TASK_SIZE) {
+ strncpy_from_user_nofault(buf, user_ptr, bufsz);
+ break;
+ }
+ fallthrough;
+#endif
+ case 'k':
+ strncpy_from_kernel_nofault(buf, unsafe_ptr, bufsz);
+ break;
+ case 'u':
+ strncpy_from_user_nofault(buf, user_ptr, bufsz);
+ break;
+ }
+}
+
/*
* Only limited trace_printk() conversion specifiers allowed:
* %d %i %u %x %ld %li %lu %lx %lld %lli %llu %llx %p %pks %pus %s
@@ -406,24 +456,8 @@ fmt_str:
break;
}
- buf[0] = 0;
- switch (fmt_ptype) {
- case 's':
-#ifdef CONFIG_ARCH_HAS_NON_OVERLAPPING_ADDRESS_SPACE
- strncpy_from_unsafe(buf, unsafe_ptr,
- sizeof(buf));
- break;
-#endif
- case 'k':
- strncpy_from_unsafe_strict(buf, unsafe_ptr,
- sizeof(buf));
- break;
- case 'u':
- strncpy_from_unsafe_user(buf,
- (__force void __user *)unsafe_ptr,
- sizeof(buf));
- break;
- }
+ bpf_trace_copy_string(buf, unsafe_ptr, fmt_ptype,
+ sizeof(buf));
goto fmt_next;
}
@@ -579,15 +613,17 @@ BPF_CALL_5(bpf_seq_printf, struct seq_file *, m, char *, fmt, u32, fmt_size,
}
if (fmt[i] == 's') {
+ void *unsafe_ptr;
+
/* try our best to copy */
if (memcpy_cnt >= MAX_SEQ_PRINTF_MAX_MEMCPY) {
err = -E2BIG;
goto out;
}
- err = strncpy_from_unsafe_strict(bufs->buf[memcpy_cnt],
- (void *) (long) args[fmt_cnt],
- MAX_SEQ_PRINTF_STR_LEN);
+ unsafe_ptr = (void *)(long)args[fmt_cnt];
+ err = strncpy_from_kernel_nofault(bufs->buf[memcpy_cnt],
+ unsafe_ptr, MAX_SEQ_PRINTF_STR_LEN);
if (err < 0)
bufs->buf[memcpy_cnt][0] = '\0';
params[fmt_cnt] = (u64)(long)bufs->buf[memcpy_cnt];
generated by cgit v1.2.3-70-g09d2 (git 2.47.1) at 2025-01-09 02:15:09 +0000