From: Martynas Pumputis <m(a)lambda.lt>
[ Upstream commit 1bb54c4071f585ebef56ce8fdfe6026fa2cbcddd ]
Previously, bpf_num_possible_cpus() had a bug when calculating a
number of possible CPUs in the case of sparse CPU allocations, as
it was considering only the first range or element of
/sys/devices/system/cpu/possible.
E.g. in the case of "0,2-3" (CPU 1 is not available), the function
returned 1 instead of 3.
This patch fixes the function by making it parse all CPU ranges and
elements.
Signed-off-by: Martynas Pumputis <m(a)lambda.lt>
Acked-by: Yonghong Song <yhs(a)fb.com>
Signed-off-by: Daniel Borkmann <daniel(a)iogearbox.net>
Signed-off-by: Sasha Levin <sashal(a)kernel.org>
---
tools/testing/selftests/bpf/bpf_util.h | 30 +++++++++++++++++---------
1 file changed, 20 insertions(+), 10 deletions(-)
diff --git a/tools/testing/selftests/bpf/bpf_util.h b/tools/testing/selftests/bpf/bpf_util.h
index 315a44fa32af3..84fd6f1bf33e7 100644
--- a/tools/testing/selftests/bpf/bpf_util.h
+++ b/tools/testing/selftests/bpf/bpf_util.h
@@ -13,7 +13,7 @@ static inline unsigned int bpf_num_possible_cpus(void)
unsigned int start, end, possible_cpus = 0;
char buff[128];
FILE *fp;
- int n;
+ int len, n, i, j = 0;
fp = fopen(fcpu, "r");
if (!fp) {
@@ -21,17 +21,27 @@ static inline unsigned int bpf_num_possible_cpus(void)
exit(1);
}
- while (fgets(buff, sizeof(buff), fp)) {
- n = sscanf(buff, "%u-%u", &start, &end);
- if (n == 0) {
- printf("Failed to retrieve # possible CPUs!\n");
- exit(1);
- } else if (n == 1) {
- end = start;
+ if (!fgets(buff, sizeof(buff), fp)) {
+ printf("Failed to read %s!\n", fcpu);
+ exit(1);
+ }
+
+ len = strlen(buff);
+ for (i = 0; i <= len; i++) {
+ if (buff[i] == ',' || buff[i] == '\0') {
+ buff[i] = '\0';
+ n = sscanf(&buff[j], "%u-%u", &start, &end);
+ if (n <= 0) {
+ printf("Failed to retrieve # possible CPUs!\n");
+ exit(1);
+ } else if (n == 1) {
+ end = start;
+ }
+ possible_cpus += end - start + 1;
+ j = i + 1;
}
- possible_cpus = start == 0 ? end + 1 : 0;
- break;
}
+
fclose(fp);
return possible_cpus;
--
2.19.1
On Wed, Nov 28, 2018 at 12:56 PM Rob Herring <robh(a)kernel.org> wrote:
>
> On Wed, Nov 28, 2018 at 1:38 PM Brendan Higgins
> <brendanhiggins(a)google.com> wrote:
> >
> > Migrate tests without any cleanup, or modifying test logic in anyway to
> > run under KUnit using the KUnit expectation and assertion API.
>
> Nice! You beat me to it. This is probably going to conflict with what
> is in the DT tree for 4.21. Also, please Cc the DT list for
> drivers/of/ changes.
>
> Looks good to me, but a few mostly formatting comments below.
I just realized that we never talked about your other comments, and I
still have some questions. (Sorry, it was the last thing I looked at
while getting v4 ready.) No worries if you don't get to it before I
send v4 out, I just didn't want you to think I was ignoring you.
>
> >
> > Signed-off-by: Brendan Higgins <brendanhiggins(a)google.com>
> > ---
> > drivers/of/Kconfig | 1 +
> > drivers/of/unittest.c | 1405 ++++++++++++++++++++++-------------------
> > 2 files changed, 752 insertions(+), 654 deletions(-)
> >
<snip>
> > diff --git a/drivers/of/unittest.c b/drivers/of/unittest.c
> > index 41b49716ac75f..a5ef44730ffdb 100644
> > --- a/drivers/of/unittest.c
> > +++ b/drivers/of/unittest.c
<snip>
> > -
> > -static void __init of_unittest_find_node_by_name(void)
> > +static void of_unittest_find_node_by_name(struct kunit *test)
>
> Why do we have to drop __init everywhere? The tests run later?
>From the standpoint of a unit test __init doesn't really make any
sense, right? I know that right now we are running as part of a
kernel, but the goal should be that a unit test is not part of a
kernel and we just include what we need.
Even so, that's the future. For now, I did not put the KUnit
infrastructure in the .init section because I didn't think it belonged
there. In practice, KUnit only knows how to run during the init phase
of the kernel, but I don't think it should be restricted there. You
should be able to run tests whenever you want because you should be
able to test anything right? I figured any restriction on that is
misleading and will potentially get in the way at worst, and
unnecessary at best especially since people shouldn't build a
production kernel with all kinds of unit tests inside.
>
> > {
> > struct device_node *np;
> > const char *options, *name;
> >
<snip>
> >
> >
> > - np = of_find_node_by_path("/testcase-data/missing-path");
> > - unittest(!np, "non-existent path returned node %pOF\n", np);
> > + KUNIT_EXPECT_EQ_MSG(test,
> > + of_find_node_by_path("/testcase-data/missing-path"),
> > + NULL,
> > + "non-existent path returned node %pOF\n", np);
>
> 1 tab indent would help with less vertical code (in general, not this
> one so much).
Will do.
>
> > of_node_put(np);
> >
> > - np = of_find_node_by_path("missing-alias");
> > - unittest(!np, "non-existent alias returned node %pOF\n", np);
> > + KUNIT_EXPECT_EQ_MSG(test, of_find_node_by_path("missing-alias"), NULL,
> > + "non-existent alias returned node %pOF\n", np);
> > of_node_put(np);
> >
> > - np = of_find_node_by_path("testcase-alias/missing-path");
> > - unittest(!np, "non-existent alias with relative path returned node %pOF\n", np);
> > + KUNIT_EXPECT_EQ_MSG(test,
> > + of_find_node_by_path("testcase-alias/missing-path"),
> > + NULL,
> > + "non-existent alias with relative path returned node %pOF\n",
> > + np);
> > of_node_put(np);
> >
<snip>
> >
> > -static void __init of_unittest_property_string(void)
> > +static void of_unittest_property_string(struct kunit *test)
> > {
> > const char *strings[4];
> > struct device_node *np;
> > int rc;
> >
> > np = of_find_node_by_path("/testcase-data/phandle-tests/consumer-a");
> > - if (!np) {
> > - pr_err("No testcase data in device tree\n");
> > - return;
> > - }
> > -
> > - rc = of_property_match_string(np, "phandle-list-names", "first");
> > - unittest(rc == 0, "first expected:0 got:%i\n", rc);
> > - rc = of_property_match_string(np, "phandle-list-names", "second");
> > - unittest(rc == 1, "second expected:1 got:%i\n", rc);
> > - rc = of_property_match_string(np, "phandle-list-names", "third");
> > - unittest(rc == 2, "third expected:2 got:%i\n", rc);
> > - rc = of_property_match_string(np, "phandle-list-names", "fourth");
> > - unittest(rc == -ENODATA, "unmatched string; rc=%i\n", rc);
> > - rc = of_property_match_string(np, "missing-property", "blah");
> > - unittest(rc == -EINVAL, "missing property; rc=%i\n", rc);
> > - rc = of_property_match_string(np, "empty-property", "blah");
> > - unittest(rc == -ENODATA, "empty property; rc=%i\n", rc);
> > - rc = of_property_match_string(np, "unterminated-string", "blah");
> > - unittest(rc == -EILSEQ, "unterminated string; rc=%i\n", rc);
> > + KUNIT_ASSERT_NOT_ERR_OR_NULL(test, np);
> > +
> > + KUNIT_EXPECT_EQ(test,
> > + of_property_match_string(np,
> > + "phandle-list-names",
> > + "first"),
> > + 0);
> > + KUNIT_EXPECT_EQ(test,
> > + of_property_match_string(np,
> > + "phandle-list-names",
> > + "second"),
> > + 1);
>
> Fewer lines on these would be better even if we go over 80 chars.
On the of_property_match_string(...), I have no opinion. I will do
whatever you like best.
Nevertheless, as far as the KUNIT_EXPECT_*(...), I do have an opinion: I am
trying to establish a good, readable convention. Given an expect statement
structured as
```
KUNIT_EXPECT_*(
test,
expect_arg_0, ..., expect_arg_n,
fmt_str, fmt_arg_0, ..., fmt_arg_n)
```
where `test` is the `struct kunit` context argument, `expect_arg_{0, ..., n}`
are the arguments the expectations is being made about (so in the above example,
`of_property_match_string(...)` and `1`), and `fmt_*` is the optional format
string that comes at the end of some expectations.
The pattern I had been trying to promote is the following:
1) If everything fits on 1 line, do that.
2) If you must make a line split, prefer to keep `test` on its own line,
`expect_arg_{0, ..., n}` should be kept together, if possible, and the format
string should follow the conventions already most commonly used with format
strings.
3) If you must split up `expect_arg_{0, ..., n}` each argument should get its
own line and should not share a line with either `test` or any `fmt_*`.
The reason I care about this so much is because expectations should be
extremely easy to read; they are the most important part of a unit
test because they tell you what the test is verifying. I am not
married to the formatting I proposed above, but I want something that
will be extremely easy to identify the arguments that the expectation
is on. Maybe that means that I need to add some syntactic fluff to
make it clearer, I don't know, but this is definitely something we
need to get right, especially in the earliest examples.
>
> > + KUNIT_EXPECT_EQ(test,
> > + of_property_match_string(np,
> > + "phandle-list-names",
> > + "third"),
> > + 2);
> > + KUNIT_EXPECT_EQ_MSG(test,
> > + of_property_match_string(np,
> > + "phandle-list-names",
> > + "fourth"),
> > + -ENODATA,
> > + "unmatched string");
> > + KUNIT_EXPECT_EQ_MSG(test,
> > + of_property_match_string(np,
> > + "missing-property",
> > + "blah"),
> > + -EINVAL,
> > + "missing property");
> > + KUNIT_EXPECT_EQ_MSG(test,
> > + of_property_match_string(np,
> > + "empty-property",
> > + "blah"),
> > + -ENODATA,
> > + "empty property");
> > + KUNIT_EXPECT_EQ_MSG(test,
> > + of_property_match_string(np,
> > + "unterminated-string",
> > + "blah"),
> > + -EILSEQ,
> > + "unterminated string");
<snip>
> > /* test insertion of a bus with parent devices */
> > -static void __init of_unittest_overlay_10(void)
> > +static void of_unittest_overlay_10(struct kunit *test)
> > {
> > - int ret;
> > char *child_path;
> >
> > /* device should disable */
> > - ret = of_unittest_apply_overlay_check(10, 10, 0, 1, PDEV_OVERLAY);
> > - if (unittest(ret == 0,
> > - "overlay test %d failed; overlay application\n", 10))
> > - return;
> > + KUNIT_ASSERT_EQ_MSG(test,
> > + of_unittest_apply_overlay_check(test,
> > + 10,
> > + 10,
> > + 0,
> > + 1,
> > + PDEV_OVERLAY),
>
> I prefer putting multiple args on a line and having fewer lines.
Looking at this now, I tend to agree, but I don't think I saw a
consistent way to break them up for these functions. I figured there
should be some type of pattern.
>
> > + 0,
> > + "overlay test %d failed; overlay application\n",
> > + 10);
> >
> > child_path = kasprintf(GFP_KERNEL, "%s/test-unittest101",
> > unittest_path(10, PDEV_OVERLAY));
> > - if (unittest(child_path, "overlay test %d failed; kasprintf\n", 10))
> > - return;
> > + KUNIT_ASSERT_NOT_ERR_OR_NULL(test, child_path);
> >
> > - ret = of_path_device_type_exists(child_path, PDEV_OVERLAY);
> > + KUNIT_EXPECT_TRUE_MSG(test,
> > + of_path_device_type_exists(child_path,
> > + PDEV_OVERLAY),
> > + "overlay test %d failed; no child device\n", 10);
> > kfree(child_path);
> > -
> > - unittest(ret, "overlay test %d failed; no child device\n", 10);
> > }
<snip>
arm64 has a feature called Top Byte Ignore, which allows to embed pointer
tags into the top byte of each pointer. Userspace programs (such as
HWASan, a memory debugging tool [1]) might use this feature and pass
tagged user pointers to the kernel through syscalls or other interfaces.
Right now the kernel is already able to handle user faults with tagged
pointers, due to these patches:
1. 81cddd65 ("arm64: traps: fix userspace cache maintenance emulation on a
tagged pointer")
2. 7dcd9dd8 ("arm64: hw_breakpoint: fix watchpoint matching for tagged
pointers")
3. 276e9327 ("arm64: entry: improve data abort handling of tagged
pointers")
When passing tagged pointers to syscalls, there's a special case of such a
pointer being passed to one of the memory syscalls (mmap, mprotect, etc.).
These syscalls don't do memory accesses but rather deal with memory
ranges, hence an untagged pointer is better suited.
This patchset extends tagged pointer support to non-memory syscalls. This
is done by reusing the untagged_addr macro to untag user pointers when the
kernel performs pointer checking to find out whether the pointer comes
from userspace (most notably in access_ok). The untagging is done only
when the pointer is being checked, the tag is preserved as the pointer
makes its way through the kernel.
One of the alternative approaches to untagging that was considered is to
completely strip the pointer tag as the pointer enters the kernel with
some kind of a syscall wrapper, but that won't work with the countless
number of different ioctl calls. With this approach we would need a custom
wrapper for each ioctl variation, which doesn't seem practical.
The following testing approaches has been taken to find potential issues
with user pointer untagging:
1. Static testing (with sparse [2] and separately with a custom static
analyzer based on Clang) to track casts of __user pointers to integer
types to find places where untagging needs to be done.
2. Dynamic testing: adding BUG_ON(has_tag(addr)) to find_vma() and running
a modified syzkaller version that passes tagged pointers to the kernel.
Based on the results of the testing the requried patches have been added
to the patchset.
This patchset has been merged into the Pixel 2 kernel tree and is now
being used to enable testing of Pixel 2 phones with HWASan.
This patchset is a prerequisite for ARM's memory tagging hardware feature
support [3].
Thanks!
[1] http://clang.llvm.org/docs/HardwareAssistedAddressSanitizerDesign.html
[2] https://github.com/lucvoo/sparse-dev/commit/5f960cb10f56ec2017c128ef9d16060…
[3] https://community.arm.com/processors/b/blog/posts/arm-a-profile-architectur…
Changes in v9:
- Rebased onto 4.20-rc6.
- Used u64 instead of __u64 in type casts in the untagged_addr macro for
arm64.
- Added braces around (addr) in the untagged_addr macro for other arches.
Changes in v8:
- Rebased onto 65102238 (4.20-rc1).
- Added a note to the cover letter on why syscall wrappers/shims that untag
user pointers won't work.
- Added a note to the cover letter that this patchset has been merged into
the Pixel 2 kernel tree.
- Documentation fixes, in particular added a list of syscalls that don't
support tagged user pointers.
Changes in v7:
- Rebased onto 17b57b18 (4.19-rc6).
- Dropped the "arm64: untag user address in __do_user_fault" patch, since
the existing patches already handle user faults properly.
- Dropped the "usb, arm64: untag user addresses in devio" patch, since the
passed pointer must come from a vma and therefore be untagged.
- Dropped the "arm64: annotate user pointers casts detected by sparse"
patch (see the discussion to the replies of the v6 of this patchset).
- Added more context to the cover letter.
- Updated Documentation/arm64/tagged-pointers.txt.
Changes in v6:
1 From 502466b9652c57a23af3bd72124144319212f30b Mon Sep 17 00:00:00 2001
- Added annotations for user pointer casts found by sparse.
1 From 502466b9652c57a23af3bd72124144319212f30b Mon Sep 17 00:00:00 2001
- Rebased onto 050cdc6c (4.19-rc1+).
1 From 502466b9652c57a23af3bd72124144319212f30b Mon Sep 17 00:00:00 2001
Changes in v5:
- Added 3 new patches that add untagging to places found with static
analysis.
- Rebased onto 44c929e1 (4.18-rc8).
Changes in v4:
- Added a selftest for checking that passing tagged pointers to the
kernel succeeds.
- Rebased onto 81e97f013 (4.18-rc1+).
Changes in v3:
- Rebased onto e5c51f30 (4.17-rc6+).
- Added linux-arch@ to the list of recipients.
Changes in v2:
- Rebased onto 2d618bdf (4.17-rc3+).
- Removed excessive untagging in gup.c.
- Removed untagging pointers returned from __uaccess_mask_ptr.
Changes in v1:
- Rebased onto 4.17-rc1.
Changes in RFC v2:
- Added "#ifndef untagged_addr..." fallback in linux/uaccess.h instead of
defining it for each arch individually.
- Updated Documentation/arm64/tagged-pointers.txt.
- Dropped "mm, arm64: untag user addresses in memory syscalls".
- Rebased onto 3eb2ce82 (4.16-rc7).
Reviewed-by: Luc Van Oostenryck <luc.vanoostenryck(a)gmail.com>
Signed-off-by: Andrey Konovalov <andreyknvl(a)google.com>
Andrey Konovalov (8):
arm64: add type casts to untagged_addr macro
uaccess: add untagged_addr definition for other arches
arm64: untag user addresses in access_ok and __uaccess_mask_ptr
mm, arm64: untag user addresses in mm/gup.c
lib, arm64: untag addrs passed to strncpy_from_user and strnlen_user
fs, arm64: untag user address in copy_mount_options
arm64: update Documentation/arm64/tagged-pointers.txt
selftests, arm64: add a selftest for passing tagged pointers to kernel
Documentation/arm64/tagged-pointers.txt | 25 +++++++++++--------
arch/arm64/include/asm/uaccess.h | 14 +++++++----
fs/namespace.c | 2 +-
include/linux/uaccess.h | 4 +++
lib/strncpy_from_user.c | 2 ++
lib/strnlen_user.c | 2 ++
mm/gup.c | 4 +++
tools/testing/selftests/arm64/.gitignore | 1 +
tools/testing/selftests/arm64/Makefile | 11 ++++++++
.../testing/selftests/arm64/run_tags_test.sh | 12 +++++++++
tools/testing/selftests/arm64/tags_test.c | 19 ++++++++++++++
11 files changed, 80 insertions(+), 16 deletions(-)
create mode 100644 tools/testing/selftests/arm64/.gitignore
create mode 100644 tools/testing/selftests/arm64/Makefile
create mode 100755 tools/testing/selftests/arm64/run_tags_test.sh
create mode 100644 tools/testing/selftests/arm64/tags_test.c
--
2.20.0.rc2.403.gdbc3b29805-goog
In environments where tput is not available, we get the following
error
$ ./ftracetest: 163: [: Illegal number:
because ncolors is an empty string. Fix that by setting it to 0 if the
tput command fails.
Acked-by: Steven Rostedt (VMware) <rostedt(a)goodmis.org>
Acked-by: Masami Hiramatsu <mhiramat(a)kernel.org>
Signed-off-by: Juerg Haefliger <juergh(a)canonical.com>
---
tools/testing/selftests/ftrace/ftracetest | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/tools/testing/selftests/ftrace/ftracetest b/tools/testing/selftests/ftrace/ftracetest
index 75244db70331..fc755e1b50f1 100755
--- a/tools/testing/selftests/ftrace/ftracetest
+++ b/tools/testing/selftests/ftrace/ftracetest
@@ -154,13 +154,13 @@ fi
# Define text colors
# Check available colors on the terminal, if any
-ncolors=`tput colors 2>/dev/null`
+ncolors=`tput colors 2>/dev/null || echo 0`
color_reset=
color_red=
color_green=
color_blue=
# If stdout exists and number of colors is eight or more, use them
-if [ -t 1 -a "$ncolors" -a "$ncolors" -ge 8 ]; then
+if [ -t 1 -a "$ncolors" -ge 8 ]; then
color_reset="\e[0m"
color_red="\e[31m"
color_green="\e[32m"
--
2.19.1