Commit Graph

9 Commits (fb447217c59a13b2fff22d94de2498c185cd9032)

Author SHA1 Message Date
Finn Thain 9a229ae249 atomic: add option for weaker alignment check
Add a new Kconfig symbol to make CONFIG_DEBUG_ATOMIC more useful on those
architectures which do not align dynamic allocations to 8-byte boundaries.
Without this, CONFIG_DEBUG_ATOMIC produces excessive WARN splats.

Link: https://lkml.kernel.org/r/6d25a12934fe9199332f4d65d17c17de450139a8.1768281748.git.fthain@linux-m68k.org
Signed-off-by: Finn Thain <fthain@linux-m68k.org>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Andrii Nakryiko <andrii@kernel.org>
Cc: Ard Biesheuvel <ardb@kernel.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Boqun Feng <boqun.feng@gmail.com>
Cc: "Borislav Petkov (AMD)" <bp@alien8.de>
Cc: Daniel Borkman <daniel@iogearbox.net>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Dinh Nguyen <dinguyen@kernel.org>
Cc: Eduard Zingerman <eddyz87@gmail.com>
Cc: Gary Guo <gary@garyguo.net>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Guo Ren <guoren@kernel.org>
Cc: Hao Luo <haoluo@google.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: John Fastabend <john.fastabend@gmail.com>
Cc: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
Cc: Jonas Bonn <jonas@southpole.se>
Cc: KP Singh <kpsingh@kernel.org>
Cc: Marc Rutland <mark.rutland@arm.com>
Cc: Martin KaFai Lau <martin.lau@linux.dev>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rich Felker <dalias@libc.org>
Cc: Sasha Levin (Microsoft) <sashal@kernel.org>
Cc: Song Liu <song@kernel.org>
Cc: Stafford Horne <shorne@gmail.com>
Cc: Stanislav Fomichev <sdf@fomichev.me>
Cc: Stefan Kristiansson <stefan.kristiansson@saunalahti.fi>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Deacon <will@kernel.org>
Cc: Yonghong Song <yonghong.song@linux.dev>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-01-26 19:07:15 -08:00
Peter Zijlstra 80047d84ee atomic: add alignment check to instrumented atomic operations
Add a Kconfig option for debug builds which logs a warning when an
instrumented atomic operation takes place that's misaligned.  Some
platforms don't trap for this.

[fthain@linux-m68k.org: added __DISABLE_EXPORTS conditional and refactored as helper function]
Link: https://lkml.kernel.org/r/51ebf844e006ca0de408f5d3a831e7b39d7fc31c.1768281748.git.fthain@linux-m68k.org
Link: https://lore.kernel.org/lkml/20250901093600.GF4067720@noisy.programming.kicks-ass.net/
Link: https://lore.kernel.org/linux-next/df9fbd22-a648-ada4-fee0-68fe4325ff82@linux-m68k.org/
Signed-off-by: Finn Thain <fthain@linux-m68k.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Suggested-by: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Sasha Levin <sashal@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Ard Biesheuvel <ardb@kernel.org>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Andrii Nakryiko <andrii@kernel.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Boqun Feng <boqun.feng@gmail.com>
Cc: Daniel Borkman <daniel@iogearbox.net>
Cc: Dinh Nguyen <dinguyen@kernel.org>
Cc: Eduard Zingerman <eddyz87@gmail.com>
Cc: Gary Guo <gary@garyguo.net>
Cc: Guo Ren <guoren@kernel.org>
Cc: Hao Luo <haoluo@google.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: John Fastabend <john.fastabend@gmail.com>
Cc: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
Cc: Jonas Bonn <jonas@southpole.se>
Cc: KP Singh <kpsingh@kernel.org>
Cc: Marc Rutland <mark.rutland@arm.com>
Cc: Martin KaFai Lau <martin.lau@linux.dev>
Cc: Rich Felker <dalias@libc.org>
Cc: Song Liu <song@kernel.org>
Cc: Stafford Horne <shorne@gmail.com>
Cc: Stanislav Fomichev <sdf@fomichev.me>
Cc: Stefan Kristiansson <stefan.kristiansson@saunalahti.fi>
Cc: Will Deacon <will@kernel.org>
Cc: Yonghong Song <yonghong.song@linux.dev>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-01-26 19:07:14 -08:00
Alexander Potapenko 922621a682 instrumented.h: add instrument_memcpy_before, instrument_memcpy_after
Bug detection tools based on compiler instrumentation may miss memory
accesses in custom memcpy implementations (such as copy_mc_to_kernel). 
Provide instrumentation hooks that tell KASAN, KCSAN, and KMSAN about such
accesses.

Link: https://lore.kernel.org/all/3b7dbd88-0861-4638-b2d2-911c97a4cadf@I-love.SAKURA.ne.jp/
Link: https://lkml.kernel.org/r/20240320101851.2589698-2-glider@google.com
Signed-off-by: Alexander Potapenko <glider@google.com>
Reviewed-by: Marco Elver <elver@google.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-04-25 21:07:02 -07:00
Randy Dunlap d70e2ecbc7 instrumented.h: Fix all kernel-doc format warnings
Fix 26 kernel-doc notation warnings by converting the function
documentation to kernel-doc format.

Warning example:

instrumented.h:155: warning: Function parameter or member 'to' not described in 'instrument_copy_from_user_after'
instrumented.h:155: warning: Function parameter or member 'from' not described in 'instrument_copy_from_user_after'
instrumented.h:155: warning: Function parameter or member 'n' not described in 'instrument_copy_from_user_after'
instrumented.h:155: warning: Function parameter or member 'left' not described in 'instrument_copy_from_user_after'

Fixes: 36e4d4dd4f ("include/linux: Add instrumented.h infrastructure")
Fixes: 00047c2e6d ("instrumented.h: Introduce read-write instrumentation hooks")
Fixes: 33b75c1d88 ("instrumented.h: allow instrumenting both sides of copy_from_user()")
Fixes: 888f84a6da ("x86: asm: instrument usercopy in get_user() and put_user()")
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Marco Elver <elver@google.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Paul E. McKenney <paulmck@kernel.org>
Cc: Ingo Molnar <mingo@kernel.org>
Reviewed-by: Marco Elver <elver@google.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2023-03-07 10:11:28 -08:00
Alexander Potapenko 75cf029027 instrumented.h: add KMSAN support
To avoid false positives, KMSAN needs to unpoison the data copied from the
userspace.  To detect infoleaks - check the memory buffer passed to
copy_to_user().

Link: https://lkml.kernel.org/r/20220915150417.722975-19-glider@google.com
Signed-off-by: Alexander Potapenko <glider@google.com>
Reviewed-by: Marco Elver <elver@google.com>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Andrey Konovalov <andreyknvl@gmail.com>
Cc: Andrey Konovalov <andreyknvl@google.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Christoph Lameter <cl@linux.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Eric Biggers <ebiggers@google.com>
Cc: Eric Biggers <ebiggers@kernel.org>
Cc: Eric Dumazet <edumazet@google.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: Ilya Leoshkevich <iii@linux.ibm.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Michael S. Tsirkin <mst@redhat.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Petr Mladek <pmladek@suse.com>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: Vegard Nossum <vegard.nossum@oracle.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-10-03 14:03:21 -07:00
Alexander Potapenko 888f84a6da x86: asm: instrument usercopy in get_user() and put_user()
Use hooks from instrumented.h to notify bug detection tools about usercopy
events in variations of get_user() and put_user().

Link: https://lkml.kernel.org/r/20220915150417.722975-5-glider@google.com
Signed-off-by: Alexander Potapenko <glider@google.com>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Andrey Konovalov <andreyknvl@gmail.com>
Cc: Andrey Konovalov <andreyknvl@google.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Christoph Lameter <cl@linux.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Eric Biggers <ebiggers@google.com>
Cc: Eric Biggers <ebiggers@kernel.org>
Cc: Eric Dumazet <edumazet@google.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: Ilya Leoshkevich <iii@linux.ibm.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Marco Elver <elver@google.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Michael S. Tsirkin <mst@redhat.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Petr Mladek <pmladek@suse.com>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: Vegard Nossum <vegard.nossum@oracle.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-10-03 14:03:18 -07:00
Alexander Potapenko 33b75c1d88 instrumented.h: allow instrumenting both sides of copy_from_user()
Introduce instrument_copy_from_user_before() and
instrument_copy_from_user_after() hooks to be invoked before and after the
call to copy_from_user().

KASAN and KCSAN will be only using instrument_copy_from_user_before(), but
for KMSAN we'll need to insert code after copy_from_user().

Link: https://lkml.kernel.org/r/20220915150417.722975-4-glider@google.com
Signed-off-by: Alexander Potapenko <glider@google.com>
Reviewed-by: Marco Elver <elver@google.com>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Andrey Konovalov <andreyknvl@gmail.com>
Cc: Andrey Konovalov <andreyknvl@google.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Christoph Lameter <cl@linux.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Eric Biggers <ebiggers@google.com>
Cc: Eric Biggers <ebiggers@kernel.org>
Cc: Eric Dumazet <edumazet@google.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: Ilya Leoshkevich <iii@linux.ibm.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Michael S. Tsirkin <mst@redhat.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Petr Mladek <pmladek@suse.com>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: Vegard Nossum <vegard.nossum@oracle.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-10-03 14:03:18 -07:00
Marco Elver 00047c2e6d instrumented.h: Introduce read-write instrumentation hooks
Introduce read-write instrumentation hooks, to more precisely denote an
operation's behaviour.

KCSAN is able to distinguish compound instrumentation, and with the new
instrumentation we then benefit from improved reporting. More
importantly, read-write compound operations should not implicitly be
treated as atomic, if they aren't actually atomic.

Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Marco Elver <elver@google.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2020-08-24 15:09:58 -07:00
Marco Elver 36e4d4dd4f include/linux: Add instrumented.h infrastructure
This adds instrumented.h, which provides generic wrappers for memory
access instrumentation that the compiler cannot emit for various
sanitizers. Currently this unifies KASAN and KCSAN instrumentation. In
future this will also include KMSAN instrumentation.

Note that, copy_{to,from}_user should use special instrumentation, since
we should be able to instrument both source and destination memory
accesses if both are kernel memory.

The current patch only instruments the memory access where the address
is always in kernel space, however, both may in fact be kernel addresses
when a compat syscall passes an argument allocated in the kernel to a
real syscall. In a future change, both KASAN and KCSAN should check both
addresses in such cases, as well as KMSAN will make use of both
addresses. [It made more sense to provide the completed function
signature, rather than updating it and changing all locations again at a
later time.]

Suggested-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Marco Elver <elver@google.com>
Acked-by: Alexander Potapenko <glider@google.com>
Reviewed-by: Dmitry Vyukov <dvyukov@google.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2020-03-21 09:41:34 +01:00