kernel/linux.git/lib, branch v5.4.50

test_objagg: Fix potential memory leak in error handling

2020-06-30T19:37:04+00:00

[ Upstream commit a6379f0ad6375a707e915518ecd5c2270afcd395 ] In case of failure of check_expect_hints_stats(), the resources allocated by objagg_hints_get should be freed. The patch fixes this issue. Signed-off-by: Aditya Pakki Signed-off-by: David S. Miller Signed-off-by: Sasha Levin

lib/zlib: remove outdated and incorrect pre-increment optimization

2020-06-24T15:50:39+00:00

[ Upstream commit acaab7335bd6f0c0b54ce3a00bd7f18222ce0f5f ] The zlib inflate code has an old micro-optimization based on the assumption that for pre-increment memory accesses, the compiler will generate code that fits better into the processor's pipeline than what would be generated for post-increment memory accesses. This optimization was already removed in upstream zlib in 2016: https://github.com/madler/zlib/commit/9aaec95e8211 This optimization causes UB according to C99, which says in section 6.5.6 "Additive operators": "If both the pointer operand and the result point to elements of the same array object, or one past the last element of the array object, the evaluation shall not produce an overflow; otherwise, the behavior is undefined". This UB is not only a theoretical concern, but can also cause trouble for future work on compiler-based sanitizers. According to the zlib commit, this optimization also is not optimal anymore with modern compilers. Replace uses of OFF, PUP and UP_UNALIGNED with their definitions in the POSTINC case, and remove the macro definitions, just like in the upstream patch. Signed-off-by: Jann Horn Signed-off-by: Andrew Morton Cc: Mikhail Zaslonko Link: http://lkml.kernel.org/r/20200507123112.252723-1-jannh@google.com Signed-off-by: Linus Torvalds Signed-off-by: Sasha Levin

kasan: stop tests being eliminated as dead code with FORTIFY_SOURCE

2020-06-22T07:31:12+00:00

[ Upstream commit adb72ae1915db28f934e9e02c18bfcea2f3ed3b7 ] Patch series "Fix some incompatibilites between KASAN and FORTIFY_SOURCE", v4. 3 KASAN self-tests fail on a kernel with both KASAN and FORTIFY_SOURCE: memchr, memcmp and strlen. When FORTIFY_SOURCE is on, a number of functions are replaced with fortified versions, which attempt to check the sizes of the operands. However, these functions often directly invoke __builtin_foo() once they have performed the fortify check. The compiler can detect that the results of these functions are not used, and knows that they have no other side effects, and so can eliminate them as dead code. Why are only memchr, memcmp and strlen affected? ================================================ Of string and string-like functions, kasan_test tests: * strchr -> not affected, no fortified version * strrchr -> likewise * strcmp -> likewise * strncmp -> likewise * strnlen -> not affected, the fortify source implementation calls the underlying strnlen implementation which is instrumented, not a builtin * strlen -> affected, the fortify souce implementation calls a __builtin version which the compiler can determine is dead. * memchr -> likewise * memcmp -> likewise * memset -> not affected, the compiler knows that memset writes to its first argument and therefore is not dead. Why does this not affect the functions normally? ================================================ In string.h, these functions are not marked as __pure, so the compiler cannot know that they do not have side effects. If relevant functions are marked as __pure in string.h, we see the following warnings and the functions are elided: lib/test_kasan.c: In function `kasan_memchr': lib/test_kasan.c:606:2: warning: statement with no effect [-Wunused-value] memchr(ptr, '1', size + 1); ^~~~~~~~~~~~~~~~~~~~~~~~~~ lib/test_kasan.c: In function `kasan_memcmp': lib/test_kasan.c:622:2: warning: statement with no effect [-Wunused-value] memcmp(ptr, arr, size+1); ^~~~~~~~~~~~~~~~~~~~~~~~ lib/test_kasan.c: In function `kasan_strings': lib/test_kasan.c:645:2: warning: statement with no effect [-Wunused-value] strchr(ptr, '1'); ^~~~~~~~~~~~~~~~ ... This annotation would make sense to add and could be added at any point, so the behaviour of test_kasan.c should change. The fix ======= Make all the functions that are pure write their results to a global, which makes them live. The strlen and memchr tests now pass. The memcmp test still fails to trigger, which is addressed in the next patch. [dja@axtens.net: drop patch 3] Link: http://lkml.kernel.org/r/20200424145521.8203-2-dja@axtens.net Fixes: 0c96350a2d2f ("lib/test_kasan.c: add tests for several string/memory API functions") Signed-off-by: Daniel Axtens Signed-off-by: Andrew Morton Tested-by: David Gow Reviewed-by: Dmitry Vyukov Cc: Daniel Micay Cc: Andrey Ryabinin Cc: Alexander Potapenko Link: http://lkml.kernel.org/r/20200423154503.5103-1-dja@axtens.net Link: http://lkml.kernel.org/r/20200423154503.5103-2-dja@axtens.net Signed-off-by: Linus Torvalds Signed-off-by: Sasha Levin

lib/mpi: Fix 64-bit MIPS build with Clang

2020-06-22T07:31:00+00:00

[ Upstream commit 18f1ca46858eac22437819937ae44aa9a8f9f2fa ] When building 64r6_defconfig with CONFIG_MIPS32_O32 disabled and CONFIG_CRYPTO_RSA enabled: lib/mpi/generic_mpih-mul1.c:37:24: error: invalid use of a cast in a inline asm context requiring an l-value: remove the cast or build with -fheinous-gnu-extensions umul_ppmm(prod_high, prod_low, s1_ptr[j], s2_limb); ~~~~~~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~ lib/mpi/longlong.h:664:22: note: expanded from macro 'umul_ppmm' : "=d" ((UDItype)(w0)) ~~~~~~~~~~^~~ lib/mpi/generic_mpih-mul1.c:37:13: error: invalid use of a cast in a inline asm context requiring an l-value: remove the cast or build with -fheinous-gnu-extensions umul_ppmm(prod_high, prod_low, s1_ptr[j], s2_limb); ~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ lib/mpi/longlong.h:668:22: note: expanded from macro 'umul_ppmm' : "=d" ((UDItype)(w1)) ~~~~~~~~~~^~~ 2 errors generated. This special case for umul_ppmm for MIPS64r6 was added in commit bbc25bee37d2b ("lib/mpi: Fix umul_ppmm() for MIPS64r6"), due to GCC being inefficient and emitting a __multi3 intrinsic. There is no such issue with clang; with this patch applied, I can build this configuration without any problems and there are no link errors like mentioned in the commit above (which I can still reproduce with GCC 9.3.0 when that commit is reverted). Only use this definition when GCC is being used. This really should have been caught by commit b0c091ae04f67 ("lib/mpi: Eliminate unused umul_ppmm definitions for MIPS") when I was messing around in this area but I was not testing 64-bit MIPS at the time. Link: https://github.com/ClangBuiltLinux/linux/issues/885 Reported-by: Dmitry Golovin Signed-off-by: Nathan Chancellor Signed-off-by: Herbert Xu Signed-off-by: Sasha Levin

lib/lzo: fix ambiguous encoding bug in lzo-rle

2020-06-17T14:40:28+00:00

commit b5265c813ce4efbfa2e46fd27cdf9a7f44a35d2e upstream. In some rare cases, for input data over 32 KB, lzo-rle could encode two different inputs to the same compressed representation, so that decompression is then ambiguous (i.e. data may be corrupted - although zram is not affected because it operates over 4 KB pages). This modifies the compressor without changing the decompressor or the bitstream format, such that: - there is no change to how data produced by the old compressor is decompressed - an old decompressor will correctly decode data from the updated compressor - performance and compression ratio are not affected - we avoid introducing a new bitstream format In testing over 12.8M real-world files totalling 903 GB, three files were affected by this bug. I also constructed 37M semi-random 64 KB files totalling 2.27 TB, and saw no affected files. Finally I tested over files constructed to contain each of the ~1024 possible bad input sequences; for all of these cases, updated lzo-rle worked correctly. There is no significant impact to performance or compression ratio. Signed-off-by: Dave Rodgman Signed-off-by: Andrew Morton Cc: Mark Rutland Cc: Dave Rodgman Cc: Willy Tarreau Cc: Sergey Senozhatsky Cc: Markus F.X.J. Oberhumer Cc: Minchan Kim Cc: Nitin Gupta Cc: Chao Yu Cc: Link: http://lkml.kernel.org/r/20200507100203.29785-1-dave.rodgman@arm.com Signed-off-by: Linus Torvalds Signed-off-by: Greg Kroah-Hartman

vsprintf: don't obfuscate NULL and error pointers

2020-05-27T15:46:43+00:00

commit 7bd57fbc4a4ddedc664cad0bbced1b469e24e921 upstream. I don't see what security concern is addressed by obfuscating NULL and IS_ERR() error pointers, printed with %p/%pK. Given the number of sites where %p is used (over 10000) and the fact that NULL pointers aren't uncommon, it probably wouldn't take long for an attacker to find the hash that corresponds to 0. Although harder, the same goes for most common error values, such as -1, -2, -11, -14, etc. The NULL part actually fixes a regression: NULL pointers weren't obfuscated until commit 3e5903eb9cff ("vsprintf: Prevent crash when dereferencing invalid pointers") which went into 5.2. I'm tacking the IS_ERR() part on here because error pointers won't leak kernel addresses and printing them as pointers shouldn't be any different from e.g. %d with PTR_ERR_OR_ZERO(). Obfuscating them just makes debugging based on existing pr_debug and friends excruciating. Note that the "always print 0's for %pK when kptr_restrict == 2" behaviour which goes way back is left as is. Example output with the patch applied: ptr error-ptr NULL %p: 0000000001f8cc5b fffffffffffffff2 0000000000000000 %pK, kptr = 0: 0000000001f8cc5b fffffffffffffff2 0000000000000000 %px: ffff888048c04020 fffffffffffffff2 0000000000000000 %pK, kptr = 1: ffff888048c04020 fffffffffffffff2 0000000000000000 %pK, kptr = 2: 0000000000000000 0000000000000000 0000000000000000 Fixes: 3e5903eb9cff ("vsprintf: Prevent crash when dereferencing invalid pointers") Signed-off-by: Ilya Dryomov Reviewed-by: Petr Mladek Reviewed-by: Sergey Senozhatsky Reviewed-by: Andy Shevchenko Acked-by: Steven Rostedt (VMware) Signed-off-by: Linus Torvalds Signed-off-by: Greg Kroah-Hartman

lib: devres: add a helper function for ioremap_uc

2020-05-10T08:31:30+00:00

[ Upstream commit e537654b7039aacfe8ae629d49655c0e5692ad44 ] Implement a resource managed strongly uncachable ioremap function. Cc: # v4.19+ Tested-by: AceLan Kao Signed-off-by: Tuowen Zhao Acked-by: Mika Westerberg Acked-by: Andy Shevchenko Acked-by: Luis Chamberlain Signed-off-by: Lee Jones Signed-off-by: Sasha Levin

lib/mpi: Fix building for powerpc with clang

2020-05-10T08:31:28+00:00

[ Upstream commit 5990cdee689c6885b27c6d969a3d58b09002b0bc ] 0day reports over and over on an powerpc randconfig with clang: lib/mpi/generic_mpih-mul1.c:37:13: error: invalid use of a cast in a inline asm context requiring an l-value: remove the cast or build with -fheinous-gnu-extensions Remove the superfluous casts, which have been done previously for x86 and arm32 in commit dea632cadd12 ("lib/mpi: fix build with clang") and commit 7b7c1df2883d ("lib/mpi/longlong.h: fix building with 32-bit x86"). Reported-by: kbuild test robot Signed-off-by: Nathan Chancellor Acked-by: Herbert Xu Signed-off-by: Michael Ellerman Link: https://github.com/ClangBuiltLinux/linux/issues/991 Link: https://lore.kernel.org/r/20200413195041.24064-1-natechancellor@gmail.com Signed-off-by: Sasha Levin

lib/raid6/test: fix build on distros whose /bin/sh is not bash

2020-04-29T14:33:00+00:00

[ Upstream commit 06bd48b6cd97ef3889b68c8e09014d81dbc463f1 ] You can build a user-space test program for the raid6 library code, like this: $ cd lib/raid6/test $ make The command in $(shell ...) function is evaluated by /bin/sh by default. (or, you can specify the shell by passing SHELL= from command line) Currently '>&/dev/null' is used to sink both stdout and stderr. Because this code is bash-ism, it only works when /bin/sh is a symbolic link to bash (this is the case on RHEL etc.) This does not work on Ubuntu where /bin/sh is a symbolic link to dash. I see lots of /bin/sh: 1: Syntax error: Bad fd number and warning "your version of binutils lacks ... support" Replace it with portable '>/dev/null 2>&1'. Fixes: 4f8c55c5ad49 ("lib/raid6: build proper files on corresponding arch") Signed-off-by: Masahiro Yamada Acked-by: H. Peter Anvin (Intel) Reviewed-by: Jason A. Donenfeld Acked-by: Ingo Molnar Reviewed-by: Nick Desaulniers Signed-off-by: Sasha Levin

kbuild, btf: Fix dependencies for DEBUG_INFO_BTF

2020-04-23T08:36:18+00:00

commit 7d32e69310d67e6b04af04f26193f79dfc2f05c7 upstream. Currently turning on DEBUG_INFO_SPLIT when DEBUG_INFO_BTF is also enabled will produce invalid btf file, since gen_btf function in link-vmlinux.sh script doesn't handle *.dwo files. Enabling DEBUG_INFO_REDUCED will also produce invalid btf file, and using GCC_PLUGIN_RANDSTRUCT with BTF makes no sense. Fixes: e83b9f55448a ("kbuild: add ability to generate BTF type info for vmlinux") Reported-by: Jann Horn Reported-by: Liu Yiding Signed-off-by: Slava Bacherikov Signed-off-by: Daniel Borkmann Reviewed-by: Kees Cook Acked-by: KP Singh Acked-by: Andrii Nakryiko Link: https://lore.kernel.org/bpf/20200402204138.408021-1-slava@bacher09.org Signed-off-by: Greg Kroah-Hartman