This patchset improves KASAN reports by making them to have
call_rcu() call stack information. It is useful for programmers
to solve use-after-free or double-free memory issue.
The KASAN report was as follows(cleaned up slightly):
BUG: KASAN: use-after-free in kasan_rcu_reclaim+0x58/0x60
Freed by task 0:
save_stack+0x24/0x50
__kasan_slab_free+0x110/0x178
kasan_slab_free+0x10/0x18
kfree+0x98/0x270
kasan_rcu_reclaim+0x1c/0x60
rcu_core+0x8b4/0x10f8
rcu_core_si+0xc/0x18
efi_header_end+0x238/0xa6c
First call_rcu() call stack:
save_stack+0x24/0x50
kasan_record_callrcu+0xc8/0xd8
call_rcu+0x190/0x580
kasan_rcu_uaf+0x1d8/0x278
Last call_rcu() call stack:
(stack is not available)
Generic KASAN will record first and last call_rcu() call stack
and print two call_rcu() call stack in KASAN report.
This feature doesn't increase the cost of memory consumption. It is
only suitable for generic KASAN.
[1]https://bugzilla.kernel.org/show_bug.cgi?id=198437
[2]https://groups.google.com/forum/#!searchin/kasan-dev/better$20stack$20traces$20for$20rcu%7Csort:date/kasan-dev/KQsjT_88hDE/7rNUZprRBgAJ
Changes since v2:
- remove new config option, default enable it in generic KASAN
- test this feature in SLAB/SLUB, it is pass.
- modify macro to be more clearly
- modify documentation
Walter Wu (3):
rcu/kasan: record and print call_rcu() call stack
kasan: record and print the free track
kasan: update documentation for generic kasan
Documentation/dev-tools/kasan.rst | 6 ++++++
include/linux/kasan.h | 2 ++
kernel/rcu/tree.c | 4 ++++
lib/Kconfig.kasan | 2 ++
mm/kasan/common.c | 26 ++++----------------------
mm/kasan/generic.c | 50 ++++++++++++++++++++++++++++++++++++++++++++++++++
mm/kasan/kasan.h | 23 +++++++++++++++++++++++
mm/kasan/report.c | 47 +++++++++++++++++++++--------------------------
mm/kasan/tags.c | 37 +++++++++++++++++++++++++++++++++++++
9 files changed, 149 insertions(+), 48 deletions(-)
On Mon, May 11, 2020 at 4:24 AM Walter Wu <[email protected]> wrote:
>
> This patchset improves KASAN reports by making them to have
> call_rcu() call stack information. It is useful for programmers
> to solve use-after-free or double-free memory issue.
Hi Walter,
I am looking at this now.
I've upload the change to gerrit [1]
https://linux-review.googlesource.com/c/linux/kernel/git/torvalds/linux/+/2458
I am not capable enough to meaningfully review such changes in this format...
[1] https://linux.googlesource.com/Documentation
> The KASAN report was as follows(cleaned up slightly):
>
> BUG: KASAN: use-after-free in kasan_rcu_reclaim+0x58/0x60
>
> Freed by task 0:
> save_stack+0x24/0x50
> __kasan_slab_free+0x110/0x178
> kasan_slab_free+0x10/0x18
> kfree+0x98/0x270
> kasan_rcu_reclaim+0x1c/0x60
> rcu_core+0x8b4/0x10f8
> rcu_core_si+0xc/0x18
> efi_header_end+0x238/0xa6c
>
> First call_rcu() call stack:
> save_stack+0x24/0x50
> kasan_record_callrcu+0xc8/0xd8
> call_rcu+0x190/0x580
> kasan_rcu_uaf+0x1d8/0x278
>
> Last call_rcu() call stack:
> (stack is not available)
>
> Generic KASAN will record first and last call_rcu() call stack
> and print two call_rcu() call stack in KASAN report.
>
> This feature doesn't increase the cost of memory consumption. It is
> only suitable for generic KASAN.
>
> [1]https://bugzilla.kernel.org/show_bug.cgi?id=198437
> [2]https://groups.google.com/forum/#!searchin/kasan-dev/better$20stack$20traces$20for$20rcu%7Csort:date/kasan-dev/KQsjT_88hDE/7rNUZprRBgAJ
>
> Changes since v2:
> - remove new config option, default enable it in generic KASAN
> - test this feature in SLAB/SLUB, it is pass.
> - modify macro to be more clearly
> - modify documentation
>
> Walter Wu (3):
> rcu/kasan: record and print call_rcu() call stack
> kasan: record and print the free track
> kasan: update documentation for generic kasan
>
> Documentation/dev-tools/kasan.rst | 6 ++++++
> include/linux/kasan.h | 2 ++
> kernel/rcu/tree.c | 4 ++++
> lib/Kconfig.kasan | 2 ++
> mm/kasan/common.c | 26 ++++----------------------
> mm/kasan/generic.c | 50 ++++++++++++++++++++++++++++++++++++++++++++++++++
> mm/kasan/kasan.h | 23 +++++++++++++++++++++++
> mm/kasan/report.c | 47 +++++++++++++++++++++--------------------------
> mm/kasan/tags.c | 37 +++++++++++++++++++++++++++++++++++++
> 9 files changed, 149 insertions(+), 48 deletions(-)
>
> --
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On Mon, 2020-05-11 at 12:01 +0200, 'Dmitry Vyukov' via kasan-dev wrote:
> On Mon, May 11, 2020 at 4:24 AM Walter Wu <[email protected]> wrote:
> >
> > This patchset improves KASAN reports by making them to have
> > call_rcu() call stack information. It is useful for programmers
> > to solve use-after-free or double-free memory issue.
>
> Hi Walter,
>
> I am looking at this now.
>
> I've upload the change to gerrit [1]
> https://linux-review.googlesource.com/c/linux/kernel/git/torvalds/linux/+/2458
>
> I am not capable enough to meaningfully review such changes in this format...
>
> [1] https://linux.googlesource.com/Documentation
>
Hi Dmitry,
I don't fully understand your meaning, our patchset's format has
problem? or?
>
> > The KASAN report was as follows(cleaned up slightly):
> >
> > BUG: KASAN: use-after-free in kasan_rcu_reclaim+0x58/0x60
> >
> > Freed by task 0:
> > save_stack+0x24/0x50
> > __kasan_slab_free+0x110/0x178
> > kasan_slab_free+0x10/0x18
> > kfree+0x98/0x270
> > kasan_rcu_reclaim+0x1c/0x60
> > rcu_core+0x8b4/0x10f8
> > rcu_core_si+0xc/0x18
> > efi_header_end+0x238/0xa6c
> >
> > First call_rcu() call stack:
> > save_stack+0x24/0x50
> > kasan_record_callrcu+0xc8/0xd8
> > call_rcu+0x190/0x580
> > kasan_rcu_uaf+0x1d8/0x278
> >
> > Last call_rcu() call stack:
> > (stack is not available)
> >
> > Generic KASAN will record first and last call_rcu() call stack
> > and print two call_rcu() call stack in KASAN report.
> >
> > This feature doesn't increase the cost of memory consumption. It is
> > only suitable for generic KASAN.
> >
> > [1]https://bugzilla.kernel.org/show_bug.cgi?id=198437
> > [2]https://groups.google.com/forum/#!searchin/kasan-dev/better$20stack$20traces$20for$20rcu%7Csort:date/kasan-dev/KQsjT_88hDE/7rNUZprRBgAJ
> >
> > Changes since v2:
> > - remove new config option, default enable it in generic KASAN
> > - test this feature in SLAB/SLUB, it is pass.
> > - modify macro to be more clearly
> > - modify documentation
> >
> > Walter Wu (3):
> > rcu/kasan: record and print call_rcu() call stack
> > kasan: record and print the free track
> > kasan: update documentation for generic kasan
> >
> > Documentation/dev-tools/kasan.rst | 6 ++++++
> > include/linux/kasan.h | 2 ++
> > kernel/rcu/tree.c | 4 ++++
> > lib/Kconfig.kasan | 2 ++
> > mm/kasan/common.c | 26 ++++----------------------
> > mm/kasan/generic.c | 50 ++++++++++++++++++++++++++++++++++++++++++++++++++
> > mm/kasan/kasan.h | 23 +++++++++++++++++++++++
> > mm/kasan/report.c | 47 +++++++++++++++++++++--------------------------
> > mm/kasan/tags.c | 37 +++++++++++++++++++++++++++++++++++++
> > 9 files changed, 149 insertions(+), 48 deletions(-)
> >
> > --
> > You received this message because you are subscribed to the Google Groups "kasan-dev" group.
> > To unsubscribe from this group and stop receiving emails from it, send an email to [email protected].
> > To view this discussion on the web visit https://groups.google.com/d/msgid/kasan-dev/20200511022359.15063-1-walter-zh.wu%40mediatek.com.
>
On Mon, May 11, 2020 at 12:32 PM Walter Wu <[email protected]> wrote:
>
> On Mon, 2020-05-11 at 12:01 +0200, 'Dmitry Vyukov' via kasan-dev wrote:
> > On Mon, May 11, 2020 at 4:24 AM Walter Wu <[email protected]> wrote:
> > >
> > > This patchset improves KASAN reports by making them to have
> > > call_rcu() call stack information. It is useful for programmers
> > > to solve use-after-free or double-free memory issue.
> >
> > Hi Walter,
> >
> > I am looking at this now.
> >
> > I've upload the change to gerrit [1]
> > https://linux-review.googlesource.com/c/linux/kernel/git/torvalds/linux/+/2458
> >
> > I am not capable enough to meaningfully review such changes in this format...
> >
> > [1] https://linux.googlesource.com/Documentation
> >
>
> Hi Dmitry,
>
> I don't fully understand your meaning, our patchset's format has
> problem? or?
No, it does not have any problems. Your patch format is standard for kernel.
It's just complex patches in the standard kernel format that are hard
to review for me.
> > > The KASAN report was as follows(cleaned up slightly):
> > >
> > > BUG: KASAN: use-after-free in kasan_rcu_reclaim+0x58/0x60
> > >
> > > Freed by task 0:
> > > save_stack+0x24/0x50
> > > __kasan_slab_free+0x110/0x178
> > > kasan_slab_free+0x10/0x18
> > > kfree+0x98/0x270
> > > kasan_rcu_reclaim+0x1c/0x60
> > > rcu_core+0x8b4/0x10f8
> > > rcu_core_si+0xc/0x18
> > > efi_header_end+0x238/0xa6c
> > >
> > > First call_rcu() call stack:
> > > save_stack+0x24/0x50
> > > kasan_record_callrcu+0xc8/0xd8
> > > call_rcu+0x190/0x580
> > > kasan_rcu_uaf+0x1d8/0x278
> > >
> > > Last call_rcu() call stack:
> > > (stack is not available)
> > >
> > > Generic KASAN will record first and last call_rcu() call stack
> > > and print two call_rcu() call stack in KASAN report.
> > >
> > > This feature doesn't increase the cost of memory consumption. It is
> > > only suitable for generic KASAN.
> > >
> > > [1]https://bugzilla.kernel.org/show_bug.cgi?id=198437
> > > [2]https://groups.google.com/forum/#!searchin/kasan-dev/better$20stack$20traces$20for$20rcu%7Csort:date/kasan-dev/KQsjT_88hDE/7rNUZprRBgAJ
> > >
> > > Changes since v2:
> > > - remove new config option, default enable it in generic KASAN
> > > - test this feature in SLAB/SLUB, it is pass.
> > > - modify macro to be more clearly
> > > - modify documentation
> > >
> > > Walter Wu (3):
> > > rcu/kasan: record and print call_rcu() call stack
> > > kasan: record and print the free track
> > > kasan: update documentation for generic kasan
> > >
> > > Documentation/dev-tools/kasan.rst | 6 ++++++
> > > include/linux/kasan.h | 2 ++
> > > kernel/rcu/tree.c | 4 ++++
> > > lib/Kconfig.kasan | 2 ++
> > > mm/kasan/common.c | 26 ++++----------------------
> > > mm/kasan/generic.c | 50 ++++++++++++++++++++++++++++++++++++++++++++++++++
> > > mm/kasan/kasan.h | 23 +++++++++++++++++++++++
> > > mm/kasan/report.c | 47 +++++++++++++++++++++--------------------------
> > > mm/kasan/tags.c | 37 +++++++++++++++++++++++++++++++++++++
> > > 9 files changed, 149 insertions(+), 48 deletions(-)
> > >
> > > --
> > > You received this message because you are subscribed to the Google Groups "kasan-dev" group.
> > > To unsubscribe from this group and stop receiving emails from it, send an email to [email protected].
> > > To view this discussion on the web visit https://groups.google.com/d/msgid/kasan-dev/20200511022359.15063-1-walter-zh.wu%40mediatek.com.
> >
>
> --
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