blake2s_compress_generic is weakly aliased by blake2s_compress. The
current harness for function selection uses a function pointer, which is
ordinarily inlined and resolved at compile time. But when Clang's CFI is
enabled, CFI still triggers when making an indirect call via a weak
symbol. This seems like a bug in Clang's CFI, as though it's bucketing
weak symbols and strong symbols differently. It also only seems to
trigger when "full LTO" mode is used, rather than "thin LTO".
[ 0.000000][ T0] Kernel panic - not syncing: CFI failure (target: blake2s_compress_generic+0x0/0x1444)
[ 0.000000][ T0] CPU: 0 PID: 0 Comm: swapper/0 Not tainted 5.16.0-mainline-06981-g076c855b846e #1
[ 0.000000][ T0] Hardware name: MT6873 (DT)
[ 0.000000][ T0] Call trace:
[ 0.000000][ T0] dump_backtrace+0xfc/0x1dc
[ 0.000000][ T0] dump_stack_lvl+0xa8/0x11c
[ 0.000000][ T0] panic+0x194/0x464
[ 0.000000][ T0] __cfi_check_fail+0x54/0x58
[ 0.000000][ T0] __cfi_slowpath_diag+0x354/0x4b0
[ 0.000000][ T0] blake2s_update+0x14c/0x178
[ 0.000000][ T0] _extract_entropy+0xf4/0x29c
[ 0.000000][ T0] crng_initialize_primary+0x24/0x94
[ 0.000000][ T0] rand_initialize+0x2c/0x6c
[ 0.000000][ T0] start_kernel+0x2f8/0x65c
[ 0.000000][ T0] __primary_switched+0xc4/0x7be4
[ 0.000000][ T0] Rebooting in 5 seconds..
Nonetheless, the function pointer method isn't so terrific anyway, so
this patch replaces it with a simple boolean, which also gets inlined
away. This successfully works around the Clang bug.
In general, I'm not too keen on all of the indirection involved here; it
clearly does more harm than good. Hopefully the whole thing can get
cleaned up down the road when lib/crypto is overhauled more
comprehensively. But for now, we go with a simple bandaid.
Fixes: 6048fdcc5f26 ("lib/crypto: blake2s: include as built-in")
Link: https://github.com/ClangBuiltLinux/linux/issues/1567
Reported-by: Miles Chen <miles.chen@mediatek.com>
Tested-by: Miles Chen <miles.chen@mediatek.com>
Tested-by: Nathan Chancellor <nathan@kernel.org>
Tested-by: John Stultz <john.stultz@linaro.org>
Acked-by: Nick Desaulniers <ndesaulniers@google.com>
Reviewed-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
(cherry picked from commit d2a02e3c8bb6b347818518edff5a4b40ff52d6d8)
Change-Id: I3a6461e3f05f57cd898f8a4f46e73fb0214037ef
Signed-off-by: Eric Biggers <ebiggers@google.com>
Add helper functions for shash implementations of BLAKE2s to
include/crypto/internal/blake2s.h, taking advantage of
__blake2s_update() and __blake2s_final() that were added by the previous
patch to share more code between the library and shash implementations.
crypto_blake2s_setkey() and crypto_blake2s_init() are usable as
shash_alg::setkey and shash_alg::init directly, while
crypto_blake2s_update() and crypto_blake2s_final() take an extra
'blake2s_compress_t' function pointer parameter. This allows the
implementation of the compression function to be overridden, which is
the only part that optimized implementations really care about.
The new functions are inline functions (similar to those in sha1_base.h,
sha256_base.h, and sm3_base.h) because this avoids needing to add a new
module blake2s_helpers.ko, they aren't *too* long, and this avoids
indirect calls which are expensive these days. Note that they can't go
in blake2s_generic.ko, as that would require selecting CRYPTO_BLAKE2S
from CRYPTO_BLAKE2S_X86, which would cause a recursive dependency.
Finally, use these new helper functions in the x86 implementation of
BLAKE2s. (This part should be a separate patch, but unfortunately the
x86 implementation used the exact same function names like
"crypto_blake2s_update()", so it had to be updated at the same time.)
Signed-off-by: Eric Biggers <ebiggers@google.com>
Acked-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
(cherry picked from commit 8c4a93a1270ddffc7660ae43fa8030ecfe9c06d9)
Conflicts:
arch/x86/crypto/blake2s-glue.c
crypto/blake2s_generic.c
(conflict due to this branch not having commit 674f368a952c,
"crypto: remove CRYPTO_TFM_RES_BAD_KEY_LEN")
Bug: 152722841
Bug: 178411248
Change-Id: I9d23b1897cee81fb1704b6eea14d3dc9b1c80fe0
Signed-off-by: Eric Biggers <ebiggers@google.com>
It doesn't make sense for the generic implementation of BLAKE2s to
include <crypto/internal/simd.h> and <linux/jump_label.h>, as these are
things that would only be useful in an architecture-specific
implementation. Remove these unnecessary includes.
Acked-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
(cherry picked from commit df412e7efda1e2c5b5fcb06701bba77434cbd1e8)
Bug: 152722841
Bug: 178411248
Change-Id: I8bccb9506d235c2b184b9899ee375fdc12d6b10f
Signed-off-by: Eric Biggers <ebiggers@google.com>
The shash_alg structs for the four variants of BLAKE2s are identical
except for the algorithm name, driver name, and digest size. So, avoid
code duplication by using a macro to define these structs.
Acked-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
(cherry picked from commit 0d396058f92ae7e5ac62839fed54bc2bba630ab5)
Bug: 152722841
Bug: 178411248
Change-Id: I32b3a6c035b18f063ad0e03c43171091ca1490a8
Signed-off-by: Eric Biggers <ebiggers@google.com>
