If the no_hash_pointers command line parameter is set, then
printk("%p") will print pointers as unhashed, which is useful for
debugging purposes. This change applies to any function that uses
vsprintf, such as print_hex_dump() and seq_buf_printf().
A large warning message is displayed if this option is enabled.
Unhashed pointers expose kernel addresses, which can be a security
risk.
Also update test_printf to skip the hashed pointer tests if the
command-line option is set.
Signed-off-by: Timur Tabi <timur@kernel.org>
Acked-by: Petr Mladek <pmladek@suse.com>
Acked-by: Randy Dunlap <rdunlap@infradead.org>
Acked-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Acked-by: Marco Elver <elver@google.com>
Signed-off-by: Petr Mladek <pmladek@suse.com>
Link: https://lore.kernel.org/r/20210214161348.369023-4-timur@kernel.org
Bug: 177201466
Bug: 180086542
(cherry picked from commit 5ead723a20e0447bc7db33dc3070b420e5f80aa6)
Signed-off-by: Alexander Potapenko <glider@google.com>
Change-Id: I9680bb5e076da9f766a66e6076e5c39291188e40
Update the kselftest framework to allow client drivers to
specify that some tests were skipped.
Signed-off-by: Timur Tabi <timur@kernel.org>
Reviewed-by: Petr Mladek <pmladek@suse.com>
Tested-by: Petr Mladek <pmladek@suse.com>
Acked-by: Marco Elver <elver@google.com>
Signed-off-by: Petr Mladek <pmladek@suse.com>
Link: https://lore.kernel.org/r/20210214161348.369023-3-timur@kernel.org
Bug: 177201466
Bug: 180086542
(cherry picked from commit d9d4de2309cd1721421c6488f1bb5744d2c83a39)
Signed-off-by: Alexander Potapenko <glider@google.com>
Change-Id: Ifbfd5c75c207d9491dd8d7d5133ea30d12a85b12
Instead of defining the total/failed test counters manually,
test drivers that are clients of kselftest should use the
macro created for this purpose.
Signed-off-by: Timur Tabi <timur@kernel.org>
Reviewed-by: Petr Mladek <pmladek@suse.com>
Acked-by: Marco Elver <elver@google.com>
Signed-off-by: Petr Mladek <pmladek@suse.com>
Link: https://lore.kernel.org/r/20210214161348.369023-2-timur@kernel.org
Bug: 177201466
Bug: 180086542
(cherry picked from commit 4e89a78779647ca7ee2967551c599633fe9d3647)
Signed-off-by: Alexander Potapenko <glider@google.com>
Change-Id: I5d60024e8214548ef1ee3a4e48b0dbc50a8adde9
Make it possible to trace KASAN error reporting. A good usecase is
watching for trace events from the userspace to detect and process memory
corruption reports from the kernel.
Link: https://lkml.kernel.org/r/20210121131915.1331302-4-glider@google.com
Signed-off-by: Alexander Potapenko <glider@google.com>
Suggested-by: Marco Elver <elver@google.com>
Cc: Andrey Konovalov <andreyknvl@google.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Petr Mladek <pmladek@suse.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Bug: 177201466
(cherry picked from commit 99bbc9fba9b0c8956b817dd21ecb510da8b676dc
https://github.com/hnaz/linux-mm v5.11-rc4-mmots-2021-01-21-20-10)
[glider: resolved conflicts in mm/kasan/report.c]
Test: CONFIG_KFENCE_KUNIT_TEST=y passes on Cuttlefish
Signed-off-by: Alexander Potapenko <glider@google.com>
Change-Id: I60ca062373d13f08ed4ed05bee341a8c28619407
Make it possible to trace KFENCE error reporting. A good usecase is
watching for trace events from the userspace to detect and process memory
corruption reports from the kernel.
Link: https://lkml.kernel.org/r/20210121131915.1331302-3-glider@google.com
Signed-off-by: Alexander Potapenko <glider@google.com>
Suggested-by: Marco Elver <elver@google.com>
Cc: Andrey Konovalov <andreyknvl@google.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Petr Mladek <pmladek@suse.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Bug: 177201466
(cherry picked from commit 2eb9559621418b844b29d2b56d9962ac019f600b
https://github.com/hnaz/linux-mm v5.11-rc4-mmots-2021-01-21-20-10)
Test: CONFIG_KFENCE_KUNIT_TEST=y passes on Cuttlefish
Signed-off-by: Alexander Potapenko <glider@google.com>
Change-Id: I991cd1eee48d107bcdf5e1c0d9194e6a386b9bdf
Patch series "Add error_report_end tracepoint to KFENCE and KASAN", v3.
This patchset adds a tracepoint, error_repor_end, that is to be used by
KFENCE, KASAN, and potentially other bug detection tools, when they print
an error report. One of the possible use cases is userspace collection of
kernel error reports: interested parties can subscribe to the tracing
event via tracefs, and get notified when an error report occurs.
This patch (of 3):
Introduce error_report_end tracepoint. It can be used in debugging tools
like KASAN, KFENCE, etc. to provide extensions to the error reporting
mechanisms (e.g. allow tests hook into error reporting, ease error report
collection from production kernels). Another benefit would be making use
of ftrace for debugging or benchmarking the tools themselves.
Should we need it, the tracepoint name leaves us with the possibility to
introduce a complementary error_report_start tracepoint in the future.
Link: https://lkml.kernel.org/r/20210121131915.1331302-1-glider@google.com
Link: https://lkml.kernel.org/r/20210121131915.1331302-2-glider@google.com
Signed-off-by: Alexander Potapenko <glider@google.com>
Suggested-by: Marco Elver <elver@google.com>
Cc: Andrey Konovalov <andreyknvl@google.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Petr Mladek <pmladek@suse.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Bug: 177201466
(cherry picked from commit ba7612c00686f204f7bca4ceb7394a9e705e84bd
https://github.com/hnaz/linux-mm v5.11-rc4-mmots-2021-01-21-20-10)
Test: CONFIG_KFENCE_KUNIT_TEST=y passes on Cuttlefish
Signed-off-by: Alexander Potapenko <glider@google.com>
Change-Id: Ic86e29982c04dad4b3b7889a424f37b22cc5f22b
Show the access type in KFENCE reports by plumbing through read/write
information from the page fault handler. Update the documentation and
test accordingly.
Link: https://lkml.kernel.org/r/20210111091544.3287013-2-elver@google.com
Signed-off-by: Marco Elver <elver@google.com>
Suggested-by: Jörn Engel <joern@purestorage.com>
Reviewed-by: Jörn Engel <joern@purestorage.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Marco Elver <elver@google.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Jann Horn <jannh@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Bug: 177201466
(cherry picked from commit e29117c1fbf30d27d5afe41cf34263e1fd8e4f04
https://github.com/hnaz/linux-mm v5.11-rc4-mmots-2021-01-21-20-10)
Test: CONFIG_KFENCE_KUNIT_TEST=y passes on Cuttlefish
Signed-off-by: Alexander Potapenko <glider@google.com>
Change-Id: I2e9bb224292cf92ac828232c51cd57024ac56d7d
Fix a typo/accidental copy-paste that resulted in the obviously
incorrect 'GFP_KERNEL * 2' expression.
Link: https://lkml.kernel.org/r/X9lHQExmHGvETxY4@elver.google.com
Signed-off-by: Marco Elver <elver@google.com>
Reported-by: kernel test robot <lkp@intel.com>
Acked-by: Alexander Potapenko <glider@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Bug: 177201466
(cherry picked from commit 161c8770c371ca3992565d8f1db1ad4a88a562e9
https://github.com/hnaz/linux-mm v5.11-rc4-mmots-2021-01-21-20-10)
Test: CONFIG_KFENCE_KUNIT_TEST=y passes on Cuttlefish
Signed-off-by: Alexander Potapenko <glider@google.com>
Change-Id: I4c26617c64fd2e6d410e6e793bb0eebf8fc87e55
Add KFENCE test suite, testing various error detection scenarios. Makes
use of KUnit for test organization. Since KFENCE's interface to obtain
error reports is via the console, the test verifies that KFENCE outputs
expected reports to the console.
Link: https://lkml.kernel.org/r/20201103175841.3495947-9-elver@google.com
Signed-off-by: Alexander Potapenko <glider@google.com>
Signed-off-by: Marco Elver <elver@google.com>
Reviewed-by: Dmitry Vyukov <dvyukov@google.com>
Co-developed-by: Alexander Potapenko <glider@google.com>
Reviewed-by: Jann Horn <jannh@google.com>
Cc: Andrey Konovalov <andreyknvl@google.com>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Christopher Lameter <cl@linux.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Eric Dumazet <edumazet@google.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Hillf Danton <hdanton@sina.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Joern Engel <joern@purestorage.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Paul E. McKenney <paulmck@kernel.org>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: SeongJae Park <sjpark@amazon.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Will Deacon <will@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Bug: 177201466
(cherry picked from commit d6364119849bb0432e9a46e9699519ea9ff1bb77
https://github.com/hnaz/linux-mm v5.11-rc4-mmots-2021-01-21-20-10)
[glider: removed memcg sanity checks from the tests]
Test: CONFIG_KFENCE_KUNIT_TEST=y passes on Cuttlefish
Signed-off-by: Alexander Potapenko <glider@google.com>
Change-Id: I733090d4109a795c078fe8090c46b19cdfe9413f
Make KFENCE compatible with KASAN. Currently this helps test KFENCE
itself, where KASAN can catch potential corruptions to KFENCE state, or
other corruptions that may be a result of freepointer corruptions in the
main allocators.
Link: https://lkml.kernel.org/r/20201103175841.3495947-7-elver@google.com
Signed-off-by: Marco Elver <elver@google.com>
Signed-off-by: Alexander Potapenko <glider@google.com>
Reviewed-by: Dmitry Vyukov <dvyukov@google.com>
Reviewed-by: Jann Horn <jannh@google.com>
Co-developed-by: Marco Elver <elver@google.com>
Cc: Andrey Konovalov <andreyknvl@google.com>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Christopher Lameter <cl@linux.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Eric Dumazet <edumazet@google.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Hillf Danton <hdanton@sina.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Joern Engel <joern@purestorage.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Paul E. McKenney <paulmck@kernel.org>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: SeongJae Park <sjpark@amazon.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Will Deacon <will@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Bug: 177201466
(cherry picked from commit 8ab944ae627dc9fb165bff68acc465751a0b8de2
https://github.com/hnaz/linux-mm v5.11-rc4-mmots-2021-01-21-20-10)
[glider: resolved a conflict in mm/kasan/generic.c]
Test: CONFIG_KFENCE_KUNIT_TEST=y passes on Cuttlefish
Signed-off-by: Alexander Potapenko <glider@google.com>
Change-Id: I2f862c2e514e7fcff50a019048c8f0d22f46e6c4
Inserts KFENCE hooks into the SLUB allocator.
To pass the originally requested size to KFENCE, add an argument
'orig_size' to slab_alloc*(). The additional argument is required to
preserve the requested original size for kmalloc() allocations, which
uses size classes (e.g. an allocation of 272 bytes will return an object
of size 512). Therefore, kmem_cache::size does not represent the
kmalloc-caller's requested size, and we must introduce the argument
'orig_size' to propagate the originally requested size to KFENCE.
Without the originally requested size, we would not be able to detect
out-of-bounds accesses for objects placed at the end of a KFENCE object
page if that object is not equal to the kmalloc-size class it was
bucketed into.
When KFENCE is disabled, there is no additional overhead, since
slab_alloc*() functions are __always_inline.
Link: https://lkml.kernel.org/r/20201103175841.3495947-6-elver@google.com
Signed-off-by: Marco Elver <elver@google.com>
Signed-off-by: Alexander Potapenko <glider@google.com>
Reviewed-by: Dmitry Vyukov <dvyukov@google.com>
Reviewed-by: Jann Horn <jannh@google.com>
Co-developed-by: Marco Elver <elver@google.com>
Cc: Andrey Konovalov <andreyknvl@google.com>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Christopher Lameter <cl@linux.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Eric Dumazet <edumazet@google.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Hillf Danton <hdanton@sina.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Joern Engel <joern@purestorage.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Paul E. McKenney <paulmck@kernel.org>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: SeongJae Park <sjpark@amazon.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Will Deacon <will@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Bug: 177201466
(cherry picked from commit 5aa4d4f541f500cd63f814ae39bea55024ed5c6b
https://github.com/hnaz/linux-mm v5.11-rc4-mmots-2021-01-21-20-10)
[glider: dropped changes to include/linux/slub_def.h,
fixed conflict in mm/slub.c,
always pass root cache pointer to kfence_alloc()]
Test: CONFIG_KFENCE_KUNIT_TEST=y passes on Cuttlefish
Signed-off-by: Alexander Potapenko <glider@google.com>
Change-Id: Iacfc22088087cb920107a595f71b09e21d5f2f47
Inserts KFENCE hooks into the SLAB allocator.
To pass the originally requested size to KFENCE, add an argument
'orig_size' to slab_alloc*(). The additional argument is required to
preserve the requested original size for kmalloc() allocations, which
uses size classes (e.g. an allocation of 272 bytes will return an object
of size 512). Therefore, kmem_cache::size does not represent the
kmalloc-caller's requested size, and we must introduce the argument
'orig_size' to propagate the originally requested size to KFENCE.
Without the originally requested size, we would not be able to detect
out-of-bounds accesses for objects placed at the end of a KFENCE object
page if that object is not equal to the kmalloc-size class it was
bucketed into.
When KFENCE is disabled, there is no additional overhead, since
slab_alloc*() functions are __always_inline.
Link: https://lkml.kernel.org/r/20201103175841.3495947-5-elver@google.com
Signed-off-by: Marco Elver <elver@google.com>
Signed-off-by: Alexander Potapenko <glider@google.com>
Reviewed-by: Dmitry Vyukov <dvyukov@google.com>
Co-developed-by: Marco Elver <elver@google.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Andrey Konovalov <andreyknvl@google.com>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Eric Dumazet <edumazet@google.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Hillf Danton <hdanton@sina.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jann Horn <jannh@google.com>
Cc: Joern Engel <joern@purestorage.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Kees Cook <keescook@chromium.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Paul E. McKenney <paulmck@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: SeongJae Park <sjpark@amazon.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Will Deacon <will@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Bug: 177201466
(cherry picked from commit 840c0553e89413319d67971a321bcc07114da9b8
https://github.com/hnaz/linux-mm v5.11-rc4-mmots-2021-01-21-20-10)
[glider: resolved minor API change in mm/slab_common.c,
dropped changes to include/linux/slab_def.h,
resolved conflicts in mm/slab.c,
always pass root cache pointer to kfence_alloc]
Test: CONFIG_KFENCE_KUNIT_TEST=y passes on Cuttlefish
Signed-off-by: Alexander Potapenko <glider@google.com>
Change-Id: Iab2ba9c7b06b9a234d93ba892be639941861f8ab
Currently in CONFIG_SLAB init_on_free happens too late, and heap objects
go to the heap quarantine not being erased.
Lets move init_on_free clearing before calling kasan_slab_free(). In that
case heap quarantine will store erased objects, similarly to CONFIG_SLUB=y
behavior.
Link: https://lkml.kernel.org/r/20201210183729.1261524-1-alex.popov@linux.com
Signed-off-by: Alexander Popov <alex.popov@linux.com>
Reviewed-by: Alexander Potapenko <glider@google.com>
Acked-by: David Rientjes <rientjes@google.com>
Acked-by: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Pekka Enberg <penberg@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Bug: 177201466
(cherry picked from commit a32d654db543843a5ffb248feaec1a909718addd
https://github.com/hnaz/linux-mm v5.11-rc4-mmots-2021-01-21-20-10)
Test: CONFIG_KFENCE_KUNIT_TEST=y passes on Cuttlefish
Signed-off-by: Alexander Potapenko <glider@google.com>
Change-Id: I2bf5e70c1524619526efd792bbdd959b813af1e4
Instead of removing the fault handling portion of the stack trace based on
the fault handler's name, just use struct pt_regs directly.
Change kfence_handle_page_fault() to take a struct pt_regs, and plumb it
through to kfence_report_error() for out-of-bounds, use-after-free, or
invalid access errors, where pt_regs is used to generate the stack trace.
If the kernel is a DEBUG_KERNEL, also show registers for more information.
Link: https://lkml.kernel.org/r/20201105092133.2075331-1-elver@google.com
Signed-off-by: Marco Elver <elver@google.com>
Suggested-by: Mark Rutland <mark.rutland@arm.com>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Jann Horn <jannh@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Bug: 177201466
(cherry picked from commit 54a5abe9b5d542ee71836439cc662efe178c8211
https://github.com/hnaz/linux-mm v5.11-rc4-mmots-2021-01-21-20-10)
Test: CONFIG_KFENCE_KUNIT_TEST=y passes on Cuttlefish
Signed-off-by: Alexander Potapenko <glider@google.com>
Change-Id: I3a60060b24f0efb4faee2e6c953973bc1263e8d1
Add architecture specific implementation details for KFENCE and enable
KFENCE for the arm64 architecture. In particular, this implements the
required interface in <asm/kfence.h>.
KFENCE requires that attributes for pages from its memory pool can
individually be set. Therefore, force the entire linear map to be mapped
at page granularity. Doing so may result in extra memory allocated for
page tables in case rodata=full is not set; however, currently
CONFIG_RODATA_FULL_DEFAULT_ENABLED=y is the default, and the common case
is therefore not affected by this change.
Link: https://lkml.kernel.org/r/20201103175841.3495947-4-elver@google.com
Signed-off-by: Alexander Potapenko <glider@google.com>
Signed-off-by: Marco Elver <elver@google.com>
Reviewed-by: Dmitry Vyukov <dvyukov@google.com>
Co-developed-by: Alexander Potapenko <glider@google.com>
Reviewed-by: Jann Horn <jannh@google.com>
Reviewed-by: Mark Rutland <mark.rutland@arm.com>
Cc: Andrey Konovalov <andreyknvl@google.com>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Christopher Lameter <cl@linux.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Eric Dumazet <edumazet@google.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Hillf Danton <hdanton@sina.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Joern Engel <joern@purestorage.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Paul E. McKenney <paulmck@kernel.org>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: SeongJae Park <sjpark@amazon.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Will Deacon <will@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Bug: 177201466
(cherry picked from commit d3cb0555da9b469c3f9ebe663d4c0d6265757175
https://github.com/hnaz/linux-mm v5.11-rc4-mmots-2021-01-21-20-10)
[glider: resolved a minor conflict in arch/arm64/Kconfig]
Test: CONFIG_KFENCE_KUNIT_TEST=y passes on Cuttlefish
Signed-off-by: Alexander Potapenko <glider@google.com>
Change-Id: Ibe9d26c2c9088862ba8855c18e0c5210a68c7f50
Add architecture specific implementation details for KFENCE and enable
KFENCE for the x86 architecture. In particular, this implements the
required interface in <asm/kfence.h> for setting up the pool and
providing helper functions for protecting and unprotecting pages.
For x86, we need to ensure that the pool uses 4K pages, which is done
using the set_memory_4k() helper function.
Link: https://lkml.kernel.org/r/20201103175841.3495947-3-elver@google.com
Signed-off-by: Marco Elver <elver@google.com>
Signed-off-by: Alexander Potapenko <glider@google.com>
Reviewed-by: Dmitry Vyukov <dvyukov@google.com>
Co-developed-by: Marco Elver <elver@google.com>
Reviewed-by: Jann Horn <jannh@google.com>
Cc: Andrey Konovalov <andreyknvl@google.com>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Christopher Lameter <cl@linux.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Eric Dumazet <edumazet@google.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Hillf Danton <hdanton@sina.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Joern Engel <joern@purestorage.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Paul E. McKenney <paulmck@kernel.org>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: SeongJae Park <sjpark@amazon.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Will Deacon <will@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Bug: 177201466
(cherry picked from commit cb99fcd83140d0d58ea36db6c1c2034abc95f983
https://github.com/hnaz/linux-mm v5.11-rc4-mmots-2021-01-21-20-10)
[glider: resolved a minor conflict in arch/x86/Kconfig,
s/flush_tlb_one_kernel/__flush_tlb_one_kernel]
Test: CONFIG_KFENCE_KUNIT_TEST=y passes on Cuttlefish
Signed-off-by: Alexander Potapenko <glider@google.com>
Change-Id: I111caffb0b88c34ed9ff57b95f127b08eacedcb9
For certain usecases, specifically where the sample interval is always
set to a very low value such as 1ms, it can make sense to use a dynamic
branch instead of static branches due to the overhead of toggling a
static branch.
Therefore, add a new Kconfig option to remove the static branches and
instead check kfence_allocation_gate if a KFENCE allocation should be
set up.
Link: https://lkml.kernel.org/r/20210111091544.3287013-1-elver@google.com
Signed-off-by: Marco Elver <elver@google.com>
Suggested-by: Jörn Engel <joern@purestorage.com>
Reviewed-by: Jörn Engel <joern@purestorage.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Jann Horn <jannh@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Bug: 177201466
(cherry picked from commit c01761611b325c1e4ec7d3e236cc9db003cb82fd
https://github.com/hnaz/linux-mm v5.11-rc4-mmots-2021-01-21-20-10)
Test: CONFIG_KFENCE_KUNIT_TEST=y passes on Cuttlefish
Signed-off-by: Alexander Potapenko <glider@google.com>
Change-Id: I68a112a8ff68fa24742b198e036f130a9757c27f
Lockdep reports that we may deadlock when calling wake_up() in
__kfence_alloc(), because we may already hold base->lock. This can happen
if debug objects are enabled:
...
__kfence_alloc+0xa0/0xbc0 mm/kfence/core.c:710
kfence_alloc include/linux/kfence.h:108 [inline]
...
kmem_cache_zalloc include/linux/slab.h:672 [inline]
fill_pool+0x264/0x5c0 lib/debugobjects.c:171
__debug_object_init+0x7a/0xd10 lib/debugobjects.c:560
debug_object_init lib/debugobjects.c:615 [inline]
debug_object_activate+0x32c/0x3e0 lib/debugobjects.c:701
debug_timer_activate kernel/time/timer.c:727 [inline]
__mod_timer+0x77d/0xe30 kernel/time/timer.c:1048
...
Therefore, switch to an open-coded wait loop. The difference to before is
that the waiter wakes up and rechecks the condition after 1 jiffy;
however, given the infrequency of kfence allocations, the difference is
insignificant.
Link: https://lkml.kernel.org/r/000000000000c0645805b7f982e4@google.com
Link: https://lkml.kernel.org/r/20210104130749.1768991-1-elver@google.com
Reported-by: syzbot+8983d6d4f7df556be565@syzkaller.appspotmail.com
Signed-off-by: Marco Elver <elver@google.com>
Suggested-by: Hillf Danton <hdanton@sina.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Jann Horn <jannh@google.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Bug: 177201466
(cherry picked from commit c5fb1ab1a3c6d0ee02d1054a10d51ffcac57aed5
https://github.com/hnaz/linux-mm v5.11-rc4-mmots-2021-01-21-20-10)
Test: CONFIG_KFENCE_KUNIT_TEST=y passes on Cuttlefish
Signed-off-by: Alexander Potapenko <glider@google.com>
Change-Id: Iee40e9f216afbc3fce8e43c0e2a4bc807fdddf39
To toggle the allocation gates, we set up a delayed work that calls
toggle_allocation_gate(). Here we use wait_event() to await an allocation
and subsequently disable the static branch again. However, if the kernel
has stopped doing allocations entirely, we'd wait indefinitely, and stall
the worker task. This may also result in the appropriate warnings if
CONFIG_DETECT_HUNG_TASK=y.
Therefore, introduce a 1 second timeout and use wait_event_timeout(). If
the timeout is reached, the static branch is disabled and a new delayed
work is scheduled to try setting up an allocation at a later time.
Note that, this scenario is very unlikely during normal workloads once the
kernel has booted and user space tasks are running. It can, however,
happen during early boot after KFENCE has been enabled, when e.g. running
tests that do not result in any allocations.
Link: https://lkml.kernel.org/r/CADYN=9J0DQhizAGB0-jz4HOBBh+05kMBXb4c0cXMS7Qi5NAJiw@mail.gmail.com
Link: https://lkml.kernel.org/r/20201110135320.3309507-1-elver@google.com
Signed-off-by: Marco Elver <elver@google.com>
Reported-by: Anders Roxell <anders.roxell@linaro.org>
Cc: Alexander Potapenko <glider@google.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: SeongJae Park <sjpark@amazon.de>
Cc: Jann Horn <jannh@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Bug: 177201466
(cherry picked from commit 80d4693491f6f20de01437319b081fdda2079e67
https://github.com/hnaz/linux-mm v5.11-rc4-mmots-2021-01-21-20-10)
Test: CONFIG_KFENCE_KUNIT_TEST=y passes on Cuttlefish
Signed-off-by: Alexander Potapenko <glider@google.com>
Change-Id: I2332ff8144b8bce5c4574b01ea2863e0e71e6124
Patch series "KFENCE: A low-overhead sampling-based memory safety error detector", v7.
This adds the Kernel Electric-Fence (KFENCE) infrastructure. KFENCE is a
low-overhead sampling-based memory safety error detector of heap
use-after-free, invalid-free, and out-of-bounds access errors. This
series enables KFENCE for the x86 and arm64 architectures, and adds
KFENCE hooks to the SLAB and SLUB allocators.
KFENCE is designed to be enabled in production kernels, and has near
zero performance overhead. Compared to KASAN, KFENCE trades performance
for precision. The main motivation behind KFENCE's design, is that with
enough total uptime KFENCE will detect bugs in code paths not typically
exercised by non-production test workloads. One way to quickly achieve a
large enough total uptime is when the tool is deployed across a large
fleet of machines.
KFENCE objects each reside on a dedicated page, at either the left or
right page boundaries. The pages to the left and right of the object
page are "guard pages", whose attributes are changed to a protected
state, and cause page faults on any attempted access to them. Such page
faults are then intercepted by KFENCE, which handles the fault
gracefully by reporting a memory access error.
Guarded allocations are set up based on a sample interval (can be set
via kfence.sample_interval). After expiration of the sample interval,
the next allocation through the main allocator (SLAB or SLUB) returns a
guarded allocation from the KFENCE object pool. At this point, the timer
is reset, and the next allocation is set up after the expiration of the
interval.
To enable/disable a KFENCE allocation through the main allocator's
fast-path without overhead, KFENCE relies on static branches via the
static keys infrastructure. The static branch is toggled to redirect the
allocation to KFENCE.
The KFENCE memory pool is of fixed size, and if the pool is exhausted no
further KFENCE allocations occur. The default config is conservative
with only 255 objects, resulting in a pool size of 2 MiB (with 4 KiB
pages).
We have verified by running synthetic benchmarks (sysbench I/O,
hackbench) and production server-workload benchmarks that a kernel with
KFENCE (using sample intervals 100-500ms) is performance-neutral
compared to a non-KFENCE baseline kernel.
KFENCE is inspired by GWP-ASan [1], a userspace tool with similar
properties. The name "KFENCE" is a homage to the Electric Fence Malloc
Debugger [2].
For more details, see Documentation/dev-tools/kfence.rst added in the
series -- also viewable here:
https://raw.githubusercontent.com/google/kasan/kfence/Documentation/dev-tools/kfence.rst
[1] http://llvm.org/docs/GwpAsan.html
[2] https://linux.die.net/man/3/efence
This patch (of 9):
This adds the Kernel Electric-Fence (KFENCE) infrastructure. KFENCE is a
low-overhead sampling-based memory safety error detector of heap
use-after-free, invalid-free, and out-of-bounds access errors.
KFENCE is designed to be enabled in production kernels, and has near
zero performance overhead. Compared to KASAN, KFENCE trades performance
for precision. The main motivation behind KFENCE's design, is that with
enough total uptime KFENCE will detect bugs in code paths not typically
exercised by non-production test workloads. One way to quickly achieve a
large enough total uptime is when the tool is deployed across a large
fleet of machines.
KFENCE objects each reside on a dedicated page, at either the left or
right page boundaries. The pages to the left and right of the object
page are "guard pages", whose attributes are changed to a protected
state, and cause page faults on any attempted access to them. Such page
faults are then intercepted by KFENCE, which handles the fault
gracefully by reporting a memory access error. To detect out-of-bounds
writes to memory within the object's page itself, KFENCE also uses
pattern-based redzones. The following figure illustrates the page
layout:
---+-----------+-----------+-----------+-----------+-----------+---
| xxxxxxxxx | O : | xxxxxxxxx | : O | xxxxxxxxx |
| xxxxxxxxx | B : | xxxxxxxxx | : B | xxxxxxxxx |
| x GUARD x | J : RED- | x GUARD x | RED- : J | x GUARD x |
| xxxxxxxxx | E : ZONE | xxxxxxxxx | ZONE : E | xxxxxxxxx |
| xxxxxxxxx | C : | xxxxxxxxx | : C | xxxxxxxxx |
| xxxxxxxxx | T : | xxxxxxxxx | : T | xxxxxxxxx |
---+-----------+-----------+-----------+-----------+-----------+---
Guarded allocations are set up based on a sample interval (can be set
via kfence.sample_interval). After expiration of the sample interval, a
guarded allocation from the KFENCE object pool is returned to the main
allocator (SLAB or SLUB). At this point, the timer is reset, and the
next allocation is set up after the expiration of the interval.
To enable/disable a KFENCE allocation through the main allocator's
fast-path without overhead, KFENCE relies on static branches via the
static keys infrastructure. The static branch is toggled to redirect the
allocation to KFENCE. To date, we have verified by running synthetic
benchmarks (sysbench I/O, hackbench) that a kernel compiled with KFENCE
is performance-neutral compared to the non-KFENCE baseline.
For more details, see Documentation/dev-tools/kfence.rst (added later in
the series).
Link: https://lkml.kernel.org/r/20201103175841.3495947-2-elver@google.com
Signed-off-by: Marco Elver <elver@google.com>
Signed-off-by: Alexander Potapenko <glider@google.com>
Reviewed-by: Dmitry Vyukov <dvyukov@google.com>
Reviewed-by: SeongJae Park <sjpark@amazon.de>
Co-developed-by: Marco Elver <elver@google.com>
Reviewed-by: Jann Horn <jannh@google.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Paul E. McKenney <paulmck@kernel.org>
Cc: Andrey Konovalov <andreyknvl@google.com>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Christopher Lameter <cl@linux.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Eric Dumazet <edumazet@google.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Hillf Danton <hdanton@sina.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Joern Engel <joern@purestorage.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Will Deacon <will@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Bug: 177201466
(cherry picked from commit 2a8dede73c3496bbd917644657f3735a4f508cb9
https://github.com/hnaz/linux-mm v5.11-rc4-mmots-2021-01-21-20-10)
[glider: dropped KCSAN bits missing in 5.4,
resolved minor conflict in init/main.c]
Test: CONFIG_KFENCE_KUNIT_TEST=y passes on Cuttlefish
Signed-off-by: Alexander Potapenko <glider@google.com>
Change-Id: I6b474675cc9732c31118df53fa06c3997f577218
The file permissions on the fdinfo dir from were changed from
S_IRUSR|S_IXUSR to S_IRUGO|S_IXUGO, and a PTRACE_MODE_READ check was added
for opening the fdinfo files [1]. However, the ptrace permission check
was not added to the directory, allowing anyone to get the open FD numbers
by reading the fdinfo directory.
Add the missing ptrace permission check for opening the fdinfo directory.
[1] https://lkml.kernel.org/r/20210308170651.919148-1-kaleshsingh@google.com
Link: https://lkml.kernel.org/r/20210713162008.1056986-1-kaleshsingh@google.com
Fixes: 7bc3fa0172a4 ("procfs: allow reading fdinfo with PTRACE_MODE_READ")
Signed-off-by: Kalesh Singh <kaleshsingh@google.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Eric W. Biederman <ebiederm@xmission.com>
Cc: Christian Brauner <christian.brauner@ubuntu.com>
Cc: Christian König <christian.koenig@amd.com>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Hridya Valsaraju <hridya@google.com>
Cc: Jann Horn <jannh@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
Bug: 151772539
Change-Id: I274b30aa0a5ce8412eae7161d31c6ee955035da9
(cherry picked from commit fc73829fa54b0c7af32d6da7c972eb3390957da4
git://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git master)
Signed-off-by: Kalesh Singh <kaleshsingh@google.com>
And 'ino' field to /proc/<pid>/fdinfo/<FD> and
/proc/<pid>/task/<tid>/fdinfo/<FD>.
The inode numbers can be used to uniquely identify DMA buffers in user
space and avoids a dependency on /proc/<pid>/fd/* when accounting
per-process DMA buffer sizes.
Link: https://lkml.kernel.org/r/20210308170651.919148-2-kaleshsingh@google.com
Signed-off-by: Kalesh Singh <kaleshsingh@google.com>
Acked-by: Randy Dunlap <rdunlap@infradead.org>
Acked-by: Christian König <christian.koenig@amd.com>
Cc: Jann Horn <jannh@google.com>
Cc: Jeff Vander Stoep <jeffv@google.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Hridya Valsaraju <hridya@google.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Kalesh Singh <kaleshsingh@google.com>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Alexey Gladkov <gladkov.alexey@gmail.com>
Cc: Szabolcs Nagy <szabolcs.nagy@arm.com>
Cc: Eric W. Biederman <ebiederm@xmission.com>
Cc: Christian Brauner <christian.brauner@ubuntu.com>
Cc: Michel Lespinasse <walken@google.com>
Cc: Bernd Edlinger <bernd.edlinger@hotmail.de>
Cc: Andrei Vagin <avagin@gmail.com>
Cc: Helge Deller <deller@gmx.de>
Cc: James Morris <jamorris@linux.microsoft.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
(cherry picked from commit 3845f256a8b527127bfbd4ced21e93d9e89aa6d7)
[Kalesh Singh - Resolve conflict in Documentation/filesystems/proc.txt]
Bug: 159126739
Bug: 167141117
Signed-off-by: Kalesh Singh <kaleshsingh@google.com>
Change-Id: Id07beac3edcc95c0b42805e24e5486965acbb46e
Android captures per-process system memory state when certain low memory
events (e.g a foreground app kill) occur, to identify potential memory
hoggers. In order to measure how much memory a process actually consumes,
it is necessary to include the DMA buffer sizes for that process in the
memory accounting. Since the handle to DMA buffers are raw FDs, it is
important to be able to identify which processes have FD references to a
DMA buffer.
Currently, DMA buffer FDs can be accounted using /proc/<pid>/fd/* and
/proc/<pid>/fdinfo -- both are only readable by the process owner, as
follows:
1. Do a readlink on each FD.
2. If the target path begins with "/dmabuf", then the FD is a dmabuf FD.
3. stat the file to get the dmabuf inode number.
4. Read/ proc/<pid>/fdinfo/<fd>, to get the DMA buffer size.
Accessing other processes' fdinfo requires root privileges. This limits
the use of the interface to debugging environments and is not suitable for
production builds. Granting root privileges even to a system process
increases the attack surface and is highly undesirable.
Since fdinfo doesn't permit reading process memory and manipulating
process state, allow accessing fdinfo under PTRACE_MODE_READ_FSCRED.
Link: https://lkml.kernel.org/r/20210308170651.919148-1-kaleshsingh@google.com
Signed-off-by: Kalesh Singh <kaleshsingh@google.com>
Suggested-by: Jann Horn <jannh@google.com>
Acked-by: Christian König <christian.koenig@amd.com>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Alexey Gladkov <gladkov.alexey@gmail.com>
Cc: Andrei Vagin <avagin@gmail.com>
Cc: Bernd Edlinger <bernd.edlinger@hotmail.de>
Cc: Christian Brauner <christian.brauner@ubuntu.com>
Cc: Eric W. Biederman <ebiederm@xmission.com>
Cc: Helge Deller <deller@gmx.de>
Cc: Hridya Valsaraju <hridya@google.com>
Cc: James Morris <jamorris@linux.microsoft.com>
Cc: Jeff Vander Stoep <jeffv@google.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Kees Cook <keescook@chromium.org>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Michel Lespinasse <walken@google.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Szabolcs Nagy <szabolcs.nagy@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
(cherry picked from commit 7bc3fa0172a423afb34e6df7a3998e5f23b1a94a)
Bug: 159126739
Bug: 167141117
Signed-off-by: Kalesh Singh <kaleshsingh@google.com>
Change-Id: I842b689670f731138592f45c7124ef446d9aa59a
Currently, SO_BINDTODEVICE requires CAP_NET_RAW. This change allows a
non-root user to bind a socket to an interface if it is not already
bound. This is useful to allow an application to bind itself to a
specific VRF for outgoing or incoming connections. Currently, an
application wanting to manage connections through several VRF need to
be privileged.
Previously, IP_UNICAST_IF and IPV6_UNICAST_IF were added for
Wine (76e21053b5 and c4062dfc42) specifically for use by
non-root processes. However, they are restricted to sendmsg() and not
usable with TCP. Allowing SO_BINDTODEVICE would allow TCP clients to
get the same privilege. As for TCP servers, outside the VRF use case,
SO_BINDTODEVICE would only further restrict connections a server could
accept.
When an application is restricted to a VRF (with `ip vrf exec`), the
socket is bound to an interface at creation and therefore, a
non-privileged call to SO_BINDTODEVICE to escape the VRF fails.
When an application bound a socket to SO_BINDTODEVICE and transmit it
to a non-privileged process through a Unix socket, a tentative to
change the bound device also fails.
Before:
>>> import socket
>>> s=socket.socket(socket.AF_INET, socket.SOCK_STREAM)
>>> s.setsockopt(socket.SOL_SOCKET, socket.SO_BINDTODEVICE, b"dummy0")
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
PermissionError: [Errno 1] Operation not permitted
After:
>>> import socket
>>> s=socket.socket(socket.AF_INET, socket.SOCK_STREAM)
>>> s.setsockopt(socket.SOL_SOCKET, socket.SO_BINDTODEVICE, b"dummy0")
>>> s.setsockopt(socket.SOL_SOCKET, socket.SO_BINDTODEVICE, b"dummy0")
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
PermissionError: [Errno 1] Operation not permitted
Bug: 323792489
Signed-off-by: Vincent Bernat <vincent@bernat.ch>
Reviewed-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
(cherry picked from commit c427bfec18f2190b8f4718785ee8ed2db4f84ee6)
Change-Id: Ie3f4c536b78da12dd961dc681c6dfb0cdf1a06b7
Signed-off-by: Peiyong Wang <wangpeiyong@xiaomi.corp-partner.google.com>
This is pretty much a no-op, but avoids changing struct net ABI.
Bug: 274789652
Test: builds, net_test
Signed-off-by: Maciej Żenczykowski <maze@google.com>
Original-Change-Id: Ia744bdf0a026adccaef8382aaecc771a8d0763a6
Change-Id: Ic22d6bb5e35a7634c1dd4d4c3ed3b142b885ec6f
It's getting more common to run nested container environments for
testing cloud software. One of such examples is Kind [1] which runs a
Kubernetes cluster in Docker containers on a single host. Each container
acts as a Kubernetes node, and thus can run any Pod (aka container)
inside the former. This approach simplifies testing a lot, as it
eliminates complicated VM setups.
Unfortunately, such a setup breaks some functionality when cgroupv2 BPF
programs are used for load-balancing. The load-balancer BPF program
needs to detect whether a request originates from the host netns or a
container netns in order to allow some access, e.g. to a service via a
loopback IP address. Typically, the programs detect this by comparing
netns cookies with the one of the init ns via a call to
bpf_get_netns_cookie(NULL). However, in nested environments the latter
cannot be used given the Kubernetes node's netns is outside the init ns.
To fix this, we need to pass the Kubernetes node netns cookie to the
program in a different way: by extending getsockopt() with a
SO_NETNS_COOKIE option, the orchestrator which runs in the Kubernetes
node netns can retrieve the cookie and pass it to the program instead.
Thus, this is following up on Eric's commit 3d368ab87cf6 ("net:
initialize net->net_cookie at netns setup") to allow retrieval via
SO_NETNS_COOKIE. This is also in line in how we retrieve socket cookie
via SO_COOKIE.
[1] https://kind.sigs.k8s.io/
Signed-off-by: Lorenz Bauer <lmb@cloudflare.com>
Signed-off-by: Martynas Pumputis <m@lambda.lt>
Cc: Eric Dumazet <edumazet@google.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
(cherry picked from commit e8b9eab99232c4e62ada9d7976c80fd5e8118289)
Bug: 274789652
Tested: builds, net_test passes
Signed-off-by: Maciej Żenczykowski <maze@google.com>
Change-Id: If784a592450af38d70f16da61e36cbbaff80ebca
Strictly speaking, seccomp filters are only used
when CONFIG_SECCOMP_FILTER.
This patch fixes the condition to enable "Seccomp_filters"
in /proc/$pid/status.
Signed-off-by: Kenta Tada <Kenta.Tada@sony.com>
Fixes: c818c03b661c ("seccomp: Report number of loaded filters in /proc/$pid/status")
Signed-off-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/OSBPR01MB26772D245E2CF4F26B76A989F5669@OSBPR01MB2677.jpnprd01.prod.outlook.com
(cherry picked from commit 64bdc0244054f7d4bb621c8b4455e292f4e421bc)
Bug: 187129171
Signed-off-by: Connor O'Brien <connoro@google.com>
Change-Id: I44541ba5bac773b10b2593e47be943536b5ce3dd
The desired behavior is to set the caller's filter count to thread's.
This value is reported via /proc, so this fixes the inaccurate count
exposed to userspace; it is not used for reference counting, etc.
Signed-off-by: Hsuan-Chi Kuo <hsuanchikuo@gmail.com>
Link: https://lore.kernel.org/r/20210304233708.420597-1-hsuanchikuo@gmail.com
Co-developed-by: Wiktor Garbacz <wiktorg@google.com>
Signed-off-by: Wiktor Garbacz <wiktorg@google.com>
Link: https://lore.kernel.org/lkml/20210810125158.329849-1-wiktorg@google.com
Signed-off-by: Kees Cook <keescook@chromium.org>
Cc: stable@vger.kernel.org
Fixes: c818c03b661c ("seccomp: Report number of loaded filters in /proc/$pid/status")
(cherry picked from commit b4d8a58f8dcfcc890f296696cadb76e77be44b5f)
Bug: 187129171
Signed-off-by: Connor O'Brien <connoro@google.com>
Change-Id: Ia3ee7ec71e9fdbb8d958f9b42b1c6e02c761503f
To enable seccomp constant action bitmaps, we need to have a static
mapping to the audit architecture and system call table size. Add these
for xtensa.
Signed-off-by: YiFei Zhu <yifeifz2@illinois.edu>
Signed-off-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/79669648ba167d668ea6ffb4884250abcd5ed254.1605101222.git.yifeifz2@illinois.edu
(cherry picked from commit 445247b02342a05b7d528bba6d85d2d418875b69)
Signed-off-by: Jeff Vander Stoep <jeffv@google.com>
Bug: 176068146
Change-Id: I7f8ecb0da495552c062e39e1b9bd5ba0aace3b01
To enable seccomp constant action bitmaps, we need to have a static
mapping to the audit architecture and system call table size. Add these
for sh.
Signed-off-by: YiFei Zhu <yifeifz2@illinois.edu>
Signed-off-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/61ae084cd4783b9b50860d9dedb4a348cf1b7b6f.1605101222.git.yifeifz2@illinois.edu
(cherry picked from commit 4c18bc054bffe415bec9e0edaa9ff1a84c1a6973)
Signed-off-by: Jeff Vander Stoep <jeffv@google.com>
Bug: 176068146
Change-Id: I4cdb3b9fda0af5e5d1e4eede11661c828f41aad5
To enable seccomp constant action bitmaps, we need to have a static
mapping to the audit architecture and system call table size. Add these
for s390.
Signed-off-by: YiFei Zhu <yifeifz2@illinois.edu>
Acked-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/a381b10aa2c5b1e583642f3cd46ced842d9d4ce5.1605101222.git.yifeifz2@illinois.edu
(cherry picked from commit c09058eda2654c37fd7ac28c2004c3aae8b988e9)
Signed-off-by: Jeff Vander Stoep <jeffv@google.com>
Bug: 176068146
Change-Id: I643cdd2a001f80bd5f6a64298e4a42412d66651e
To enable seccomp constant action bitmaps, we need to have a static
mapping to the audit architecture and system call table size. Add these
for powerpc.
__LITTLE_ENDIAN__ is used here instead of CONFIG_CPU_LITTLE_ENDIAN
to keep it consistent with asm/syscall.h.
Signed-off-by: YiFei Zhu <yifeifz2@illinois.edu>
Signed-off-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/0b64925362671cdaa26d01bfe50b3ba5e164adfd.1605101222.git.yifeifz2@illinois.edu
(cherry picked from commit e7bcb4622ddf4473da6c03fa8423919a568c57dc)
Signed-off-by: Jeff Vander Stoep <jeffv@google.com>
Bug: 176068146
Change-Id: I917b30a0c8cc6697513cc7f12bc84691e3166745
To enable seccomp constant action bitmaps, we need to have a static
mapping to the audit architecture and system call table size. Add these
for parisc.
Signed-off-by: YiFei Zhu <yifeifz2@illinois.edu>
Acked-by: Helge Deller <deller@gmx.de>
Signed-off-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/9bb86c546eda753adf5270425e7353202dbce87c.1605101222.git.yifeifz2@illinois.edu
(cherry picked from commit 6aa7923c8737d1f8fd2a06154155d68dec646464)
Signed-off-by: Jeff Vander Stoep <jeffv@google.com>
Bug: 176068146
Change-Id: I48ef86a4127b9cc87dff5235ded3733c098db7e1
To enable seccomp constant action bitmaps, we need to have a static
mapping to the audit architecture and system call table size. Add these
for csky.
Signed-off-by: YiFei Zhu <yifeifz2@illinois.edu>
Signed-off-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/f9219026d4803b22f3e57e3768b4e42e004ef236.1605101222.git.yifeifz2@illinois.edu
(cherry picked from commit 6e9ae6f98809e0d123ff4d769ba2e6f652119138)
Signed-off-by: Jeff Vander Stoep <jeffv@google.com>
Bug: 176068146
Change-Id: I1fea89150f06be98ea4ee4357ad441e60aa6589f
To enable seccomp constant action bitmaps, we need to have a static
mapping to the audit architecture and system call table size. Add these
for arm.
Signed-off-by: Kees Cook <keescook@chromium.org>
(cherry picked from commit 424c9102fa7b2a5c15afe47fd14278c849f4eefb)
Signed-off-by: Jeff Vander Stoep <jeffv@google.com>
Change-Id: I90eaafdc43f618ce7dcf76e1cbb8ae1ff542ead9
Bug: 176068146
To enable seccomp constant action bitmaps, we need to have a static
mapping to the audit architecture and system call table size. Add these
for arm64.
Signed-off-by: Kees Cook <keescook@chromium.org>
(cherry picked from commit ffde703470b03b1000017ed35c4f90a90caa22cf)
Signed-off-by: Jeff Vander Stoep <jeffv@google.com>
Change-Id: Ib21059de0928a61bd76202a67732432e88c5a5f0
Bug: 176068146
As seccomp_benchmark tries to calibrate how many samples will take more
than 5 seconds to execute, it may end up picking up a number of samples
that take 10 (but up to 12) seconds. As the calibration will take double
that time, it takes around 20 seconds. Then, it executes the whole thing
again, and then once more, with some added overhead. So, the thing might
take more than 40 seconds, which is too close to the 45s timeout.
That is very dependent on the system where it's executed, so may not be
observed always, but it has been observed on x86 VMs. Using a 90s timeout
seems safe enough.
Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@canonical.com>
Link: https://lore.kernel.org/r/20200601123202.1183526-1-cascardo@canonical.com
Signed-off-by: Kees Cook <keescook@chromium.org>
(cherry picked from commit bc32c9c86581abf7baacf71342df3b0affe367db)
Signed-off-by: Jeff Vander Stoep <jeffv@google.com>
Bug: 176068146
Change-Id: I52379d62bddc9163c6cbbb934483ceabb10cc909
The seccomp benchmark calibration loop did not need to take so long.
Instead, use a simple 1 second timeout and multiply up to target. It
does not need to be accurate.
Signed-off-by: Kees Cook <keescook@chromium.org>
(cherry picked from commit 81a0c8bc82be7c15dbf3e54832334552e6b76e2b)
Signed-off-by: Jeff Vander Stoep <jeffv@google.com>
Bug: 176068146
Change-Id: I5583b28bb635c01413548dbe05b2bed8d50def00
It's useful to see how much (at a minimum) each filter adds to the
syscall overhead. Add additional calculations.
Signed-off-by: Kees Cook <keescook@chromium.org>
(cherry picked from commit d3a37ea9f6e548388b83fe895c7a037bc2ec3f7f)
Signed-off-by: Jeff Vander Stoep <jeffv@google.com>
Bug: 176068146
Change-Id: Ibc36b007b580cc129b2880b12b151a659590abb9
Provide seccomp internals with the details to calculate which syscall
table the running kernel is expecting to deal with. This allows for
efficient architecture pinning and paves the way for constant-action
bitmaps.
Co-developed-by: YiFei Zhu <yifeifz2@illinois.edu>
Signed-off-by: YiFei Zhu <yifeifz2@illinois.edu>
Signed-off-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/da58c3733d95c4f2115dd94225dfbe2573ba4d87.1602431034.git.yifeifz2@illinois.edu
(cherry picked from commit 25db91209a910a0ccf8b093743088d0f4bf5659f)
Signed-off-by: Jeff Vander Stoep <jeffv@google.com>
Change-Id: I48a434063e401b27834e4ba37b88a852da51300b
Bug: 176068146
SECCOMP_CACHE will only operate on syscalls that do not access
any syscall arguments or instruction pointer. To facilitate
this we need a static analyser to know whether a filter will
return allow regardless of syscall arguments for a given
architecture number / syscall number pair. This is implemented
here with a pseudo-emulator, and stored in a per-filter bitmap.
In order to build this bitmap at filter attach time, each filter is
emulated for every syscall (under each possible architecture), and
checked for any accesses of struct seccomp_data that are not the "arch"
nor "nr" (syscall) members. If only "arch" and "nr" are examined, and
the program returns allow, then we can be sure that the filter must
return allow independent from syscall arguments.
Nearly all seccomp filters are built from these cBPF instructions:
BPF_LD | BPF_W | BPF_ABS
BPF_JMP | BPF_JEQ | BPF_K
BPF_JMP | BPF_JGE | BPF_K
BPF_JMP | BPF_JGT | BPF_K
BPF_JMP | BPF_JSET | BPF_K
BPF_JMP | BPF_JA
BPF_RET | BPF_K
BPF_ALU | BPF_AND | BPF_K
Each of these instructions are emulated. Any weirdness or loading
from a syscall argument will cause the emulator to bail.
The emulation is also halted if it reaches a return. In that case,
if it returns an SECCOMP_RET_ALLOW, the syscall is marked as good.
Emulator structure and comments are from Kees [1] and Jann [2].
Emulation is done at attach time. If a filter depends on more
filters, and if the dependee does not guarantee to allow the
syscall, then we skip the emulation of this syscall.
[1] https://lore.kernel.org/lkml/20200923232923.3142503-5-keescook@chromium.org/
[2] https://lore.kernel.org/lkml/CAG48ez1p=dR_2ikKq=xVxkoGg0fYpTBpkhJSv1w-6BG=76PAvw@mail.gmail.com/
Suggested-by: Jann Horn <jannh@google.com>
Signed-off-by: YiFei Zhu <yifeifz2@illinois.edu>
Reviewed-by: Jann Horn <jannh@google.com>
Co-developed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/71c7be2db5ee08905f41c3be5c1ad6e2601ce88f.1602431034.git.yifeifz2@illinois.edu
(cherry picked from commit 8e01b51a31a1e08e2c3e8fcc0ef6790441be2f61)
Signed-off-by: Jeff Vander Stoep <jeffv@google.com>
Change-Id: I5047f7f0d6502e5de6c047743f1053fda3025a6e
Bug: 176068146
