kernel/linux.git/lib, branch v5.15.38

hex2bin: fix access beyond string end

2022-05-09T07:14:30+00:00

commit e4d8a29997731b3bb14059024b24df9f784288d0 upstream. If we pass too short string to "hex2bin" (and the string size without the terminating NUL character is even), "hex2bin" reads one byte after the terminating NUL character. This patch fixes it. Note that hex_to_bin returns -1 on error and hex2bin return -EINVAL on error - so we can't just return the variable "hi" or "lo" on error. This inconsistency may be fixed in the next merge window, but for the purpose of fixing this bug, we just preserve the existing behavior and return -1 and -EINVAL. Signed-off-by: Mikulas Patocka Reviewed-by: Andy Shevchenko Fixes: b78049831ffe ("lib: add error checking to hex2bin") Cc: stable@vger.kernel.org Signed-off-by: Linus Torvalds Signed-off-by: Greg Kroah-Hartman

hex2bin: make the function hex_to_bin constant-time

2022-05-09T07:14:30+00:00

commit e5be15767e7e284351853cbaba80cde8620341fb upstream. The function hex2bin is used to load cryptographic keys into device mapper targets dm-crypt and dm-integrity. It should take constant time independent on the processed data, so that concurrently running unprivileged code can't infer any information about the keys via microarchitectural convert channels. This patch changes the function hex_to_bin so that it contains no branches and no memory accesses. Note that this shouldn't cause performance degradation because the size of the new function is the same as the size of the old function (on x86-64) - and the new function causes no branch misprediction penalties. I compile-tested this function with gcc on aarch64 alpha arm hppa hppa64 i386 ia64 m68k mips32 mips64 powerpc powerpc64 riscv sh4 s390x sparc32 sparc64 x86_64 and with clang on aarch64 arm hexagon i386 mips32 mips64 powerpc powerpc64 s390x sparc32 sparc64 x86_64 to verify that there are no branches in the generated code. Signed-off-by: Mikulas Patocka Cc: stable@vger.kernel.org Signed-off-by: Linus Torvalds Signed-off-by: Greg Kroah-Hartman

iov_iter: Introduce nofault flag to disable page faults

2022-05-01T15:22:33+00:00

commit 3337ab08d08b1a375f88471d9c8b1cac968cb054 upstream Introduce a new nofault flag to indicate to iov_iter_get_pages not to fault in user pages. This is implemented by passing the FOLL_NOFAULT flag to get_user_pages, which causes get_user_pages to fail when it would otherwise fault in a page. We'll use the ->nofault flag to prevent iomap_dio_rw from faulting in pages when page faults are not allowed. Signed-off-by: Andreas Gruenbacher Signed-off-by: Anand Jain Signed-off-by: Greg Kroah-Hartman

iov_iter: Introduce fault_in_iov_iter_writeable

2022-05-01T15:22:29+00:00

commit cdd591fc86e38ad3899196066219fbbd845f3162 upstream Introduce a new fault_in_iov_iter_writeable helper for safely faulting in an iterator for writing. Uses get_user_pages() to fault in the pages without actually writing to them, which would be destructive. We'll use fault_in_iov_iter_writeable in gfs2 once we've determined that the iterator passed to .read_iter isn't in memory. Signed-off-by: Andreas Gruenbacher Signed-off-by: Anand Jain Signed-off-by: Greg Kroah-Hartman

iov_iter: Turn iov_iter_fault_in_readable into fault_in_iov_iter_readable

2022-05-01T15:22:28+00:00

commit a6294593e8a1290091d0b078d5d33da5e0cd3dfe upstream Turn iov_iter_fault_in_readable into a function that returns the number of bytes not faulted in, similar to copy_to_user, instead of returning a non-zero value when any of the requested pages couldn't be faulted in. This supports the existing users that require all pages to be faulted in as well as new users that are happy if any pages can be faulted in. Rename iov_iter_fault_in_readable to fault_in_iov_iter_readable to make sure this change doesn't silently break things. Signed-off-by: Andreas Gruenbacher Signed-off-by: Anand Jain Signed-off-by: Greg Kroah-Hartman

gup: Turn fault_in_pages_{readable,writeable} into fault_in_{readable,writeable}

2022-05-01T15:22:28+00:00

commit bb523b406c849eef8f265a07cd7f320f1f177743 upstream Turn fault_in_pages_{readable,writeable} into versions that return the number of bytes not faulted in, similar to copy_to_user, instead of returning a non-zero value when any of the requested pages couldn't be faulted in. This supports the existing users that require all pages to be faulted in as well as new users that are happy if any pages can be faulted in. Rename the functions to fault_in_{readable,writeable} to make sure this change doesn't silently break things. Neither of these functions is entirely trivial and it doesn't seem useful to inline them, so move them to mm/gup.c. Signed-off-by: Andreas Gruenbacher Signed-off-by: Anand Jain Signed-off-by: Greg Kroah-Hartman

stacktrace: move filter_irq_stacks() to kernel/stacktrace.c

2022-04-13T18:59:28+00:00

commit f39f21b3ddc7fc0f87eb6dc75ddc81b5bbfb7672 upstream. filter_irq_stacks() has little to do with the stackdepot implementation, except that it is usually used by users (such as KASAN) of stackdepot to reduce the stack trace. However, filter_irq_stacks() itself is not useful without a stack trace as obtained by stack_trace_save() and friends. Therefore, move filter_irq_stacks() to kernel/stacktrace.c, so that new users of filter_irq_stacks() do not have to start depending on STACKDEPOT only for filter_irq_stacks(). Link: https://lkml.kernel.org/r/20210923104803.2620285-1-elver@google.com Signed-off-by: Marco Elver Acked-by: Dmitry Vyukov Cc: Alexander Potapenko Cc: Jann Horn Cc: Aleksandr Nogikh Cc: Taras Madan Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Greg Kroah-Hartman

ubsan: remove CONFIG_UBSAN_OBJECT_SIZE

2022-04-13T18:59:27+00:00

commit 69d0db01e210e07fe915e5da91b54a867cda040f upstream. The object-size sanitizer is redundant to -Warray-bounds, and inappropriately performs its checks at run-time when all information needed for the evaluation is available at compile-time, making it quite difficult to use: https://bugzilla.kernel.org/show_bug.cgi?id=214861 With -Warray-bounds almost enabled globally, it doesn't make sense to keep this around. Link: https://lkml.kernel.org/r/20211203235346.110809-1-keescook@chromium.org Signed-off-by: Kees Cook Reviewed-by: Marco Elver Cc: Masahiro Yamada Cc: Michal Marek Cc: Nick Desaulniers Cc: Nathan Chancellor Cc: Andrey Ryabinin Cc: "Peter Zijlstra (Intel)" Cc: Stephen Rothwell Cc: Arnd Bergmann Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Cc: Tadeusz Struk Signed-off-by: Greg Kroah-Hartman

lz4: fix LZ4_decompress_safe_partial read out of bound

2022-04-13T18:59:21+00:00

commit eafc0a02391b7b36617b36c97c4b5d6832cf5e24 upstream. When partialDecoding, it is EOF if we've either filled the output buffer or can't proceed with reading an offset for following match. In some extreme corner cases when compressed data is suitably corrupted, UAF will occur. As reported by KASAN [1], LZ4_decompress_safe_partial may lead to read out of bound problem during decoding. lz4 upstream has fixed it [2] and this issue has been disscussed here [3] before. current decompression routine was ported from lz4 v1.8.3, bumping lib/lz4 to v1.9.+ is certainly a huge work to be done later, so, we'd better fix it first. [1] https://lore.kernel.org/all/000000000000830d1205cf7f0477@google.com/ [2] https://github.com/lz4/lz4/commit/c5d6f8a8be3927c0bec91bcc58667a6cfad244ad# [3] https://lore.kernel.org/all/CC666AE8-4CA4-4951-B6FB-A2EFDE3AC03B@fb.com/ Link: https://lkml.kernel.org/r/20211111105048.2006070-1-guoxuenan@huawei.com Reported-by: syzbot+63d688f1d899c588fb71@syzkaller.appspotmail.com Signed-off-by: Guo Xuenan Reviewed-by: Nick Terrell Acked-by: Gao Xiang Cc: Yann Collet Cc: Chengyang Fan Cc: Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Greg Kroah-Hartman

lib/Kconfig.debug: add ARCH dependency for FUNCTION_ALIGN option

2022-04-13T18:59:10+00:00

[ Upstream commit 1bf18da62106225dbc47aab41efee2aeb99caccd ] 0Day robots reported there is compiling issue for 'csky' ARCH when CONFIG_DEBUG_FORCE_DATA_SECTION_ALIGNED is enabled [1]: All errors (new ones prefixed by >>): {standard input}: Assembler messages: >> {standard input}:2277: Error: pcrel offset for branch to .LS000B too far (0x3c) Which was discussed in [2]. And as there is no solution for csky yet, add some dependency for this config to limit it to several ARCHs which have no compiling issue so far. [1]. https://lore.kernel.org/lkml/202202271612.W32UJAj2-lkp@intel.com/ [2]. https://www.spinics.net/lists/linux-kbuild/msg30298.html Link: https://lkml.kernel.org/r/20220304021100.GN4548@shbuild999.sh.intel.com Reported-by: kernel test robot Signed-off-by: Feng Tang Cc: Guo Ren Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Sasha Levin