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authorDan Williams <dan.j.williams@intel.com>2021-06-08 17:16:11 -0700
committerDan Williams <dan.j.williams@intel.com>2021-06-08 17:16:11 -0700
commit54ada34b4dfdb864ac602e13ff87581abe517ce9 (patch)
tree8c92ca68c13e86b71f9cbf05a1a432c3ba4ea67b /kernel/trace
parentcxl/pci: Fixup devm_cxl_iomap_block() to take a 'struct device *' (diff)
parentACPICA: Add the CFMWS structure definition to the CEDT table (diff)
Merge branch 'rafael/acpica/cfmws' into for-5.14/cxl
Pick up the definition of the CXL Fixed Memory Window Structure from Rafael's ACPICA development branch.
Diffstat (limited to 'kernel/trace')
-rw-r--r--kernel/trace/bpf_trace.c32
-rw-r--r--kernel/trace/trace.c31
2 files changed, 39 insertions, 24 deletions
diff --git a/kernel/trace/bpf_trace.c b/kernel/trace/bpf_trace.c
index d2d7cf6cfe83..7a52bc172841 100644
--- a/kernel/trace/bpf_trace.c
+++ b/kernel/trace/bpf_trace.c
@@ -215,16 +215,11 @@ 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)
{
- int ret = security_locked_down(LOCKDOWN_BPF_READ);
+ int ret;
- if (unlikely(ret < 0))
- goto fail;
ret = copy_from_kernel_nofault(dst, unsafe_ptr, size);
if (unlikely(ret < 0))
- goto fail;
- return ret;
-fail:
- memset(dst, 0, size);
+ memset(dst, 0, size);
return ret;
}
@@ -246,10 +241,7 @@ const struct bpf_func_proto bpf_probe_read_kernel_proto = {
static __always_inline int
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 fail;
+ int ret;
/*
* The strncpy_from_kernel_nofault() call will likely not fill the
@@ -262,11 +254,7 @@ bpf_probe_read_kernel_str_common(void *dst, u32 size, const void *unsafe_ptr)
*/
ret = strncpy_from_kernel_nofault(dst, unsafe_ptr, size);
if (unlikely(ret < 0))
- goto fail;
-
- return ret;
-fail:
- memset(dst, 0, size);
+ memset(dst, 0, size);
return ret;
}
@@ -1011,16 +999,20 @@ bpf_tracing_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
case BPF_FUNC_probe_read_user:
return &bpf_probe_read_user_proto;
case BPF_FUNC_probe_read_kernel:
- return &bpf_probe_read_kernel_proto;
+ return security_locked_down(LOCKDOWN_BPF_READ) < 0 ?
+ NULL : &bpf_probe_read_kernel_proto;
case BPF_FUNC_probe_read_user_str:
return &bpf_probe_read_user_str_proto;
case BPF_FUNC_probe_read_kernel_str:
- return &bpf_probe_read_kernel_str_proto;
+ return security_locked_down(LOCKDOWN_BPF_READ) < 0 ?
+ NULL : &bpf_probe_read_kernel_str_proto;
#ifdef CONFIG_ARCH_HAS_NON_OVERLAPPING_ADDRESS_SPACE
case BPF_FUNC_probe_read:
- return &bpf_probe_read_compat_proto;
+ return security_locked_down(LOCKDOWN_BPF_READ) < 0 ?
+ NULL : &bpf_probe_read_compat_proto;
case BPF_FUNC_probe_read_str:
- return &bpf_probe_read_compat_str_proto;
+ return security_locked_down(LOCKDOWN_BPF_READ) < 0 ?
+ NULL : &bpf_probe_read_compat_str_proto;
#endif
#ifdef CONFIG_CGROUPS
case BPF_FUNC_get_current_cgroup_id:
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index 560e4c8d3825..a21ef9cd2aae 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -3704,6 +3704,9 @@ void trace_check_vprintf(struct trace_iterator *iter, const char *fmt,
goto print;
while (*p) {
+ bool star = false;
+ int len = 0;
+
j = 0;
/* We only care about %s and variants */
@@ -3725,13 +3728,17 @@ void trace_check_vprintf(struct trace_iterator *iter, const char *fmt,
/* Need to test cases like %08.*s */
for (j = 1; p[i+j]; j++) {
if (isdigit(p[i+j]) ||
- p[i+j] == '*' ||
p[i+j] == '.')
continue;
+ if (p[i+j] == '*') {
+ star = true;
+ continue;
+ }
break;
}
if (p[i+j] == 's')
break;
+ star = false;
}
j = 0;
}
@@ -3744,6 +3751,9 @@ void trace_check_vprintf(struct trace_iterator *iter, const char *fmt,
iter->fmt[i] = '\0';
trace_seq_vprintf(&iter->seq, iter->fmt, ap);
+ if (star)
+ len = va_arg(ap, int);
+
/* The ap now points to the string data of the %s */
str = va_arg(ap, const char *);
@@ -3762,8 +3772,18 @@ void trace_check_vprintf(struct trace_iterator *iter, const char *fmt,
int ret;
/* Try to safely read the string */
- ret = strncpy_from_kernel_nofault(iter->fmt, str,
- iter->fmt_size);
+ if (star) {
+ if (len + 1 > iter->fmt_size)
+ len = iter->fmt_size - 1;
+ if (len < 0)
+ len = 0;
+ ret = copy_from_kernel_nofault(iter->fmt, str, len);
+ iter->fmt[len] = 0;
+ star = false;
+ } else {
+ ret = strncpy_from_kernel_nofault(iter->fmt, str,
+ iter->fmt_size);
+ }
if (ret < 0)
trace_seq_printf(&iter->seq, "(0x%px)", str);
else
@@ -3775,7 +3795,10 @@ void trace_check_vprintf(struct trace_iterator *iter, const char *fmt,
strncpy(iter->fmt, p + i, j + 1);
iter->fmt[j+1] = '\0';
}
- trace_seq_printf(&iter->seq, iter->fmt, str);
+ if (star)
+ trace_seq_printf(&iter->seq, iter->fmt, len, str);
+ else
+ trace_seq_printf(&iter->seq, iter->fmt, str);
p += i + j + 1;
}