| Message ID | 20201006163326.2780619-1-jeremy.linton@arm.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | [BUG,v3] crypto: arm64: Use x16 with indirect branch to bti_c | expand |
On Tue, 6 Oct 2020 at 18:33, Jeremy Linton <jeremy.linton@arm.com> wrote: > > The AES code uses a 'br x7' as part of a function called by > a macro. That branch needs a bti_j as a target. This results > in a panic as seen below. Using x16 (or x17) with an indirect > branch keeps the target bti_c. > > Bad mode in Synchronous Abort handler detected on CPU1, code 0x34000003 -- BTI > CPU: 1 PID: 265 Comm: cryptomgr_test Not tainted 5.8.11-300.fc33.aarch64 #1 > pstate: 20400c05 (nzCv daif +PAN -UAO BTYPE=j-) > pc : aesbs_encrypt8+0x0/0x5f0 [aes_neon_bs] > lr : aesbs_xts_encrypt+0x48/0xe0 [aes_neon_bs] > sp : ffff80001052b730 > > aesbs_encrypt8+0x0/0x5f0 [aes_neon_bs] > __xts_crypt+0xb0/0x2dc [aes_neon_bs] > xts_encrypt+0x28/0x3c [aes_neon_bs] > crypto_skcipher_encrypt+0x50/0x84 > simd_skcipher_encrypt+0xc8/0xe0 > crypto_skcipher_encrypt+0x50/0x84 > test_skcipher_vec_cfg+0x224/0x5f0 > test_skcipher+0xbc/0x120 > alg_test_skcipher+0xa0/0x1b0 > alg_test+0x3dc/0x47c > cryptomgr_test+0x38/0x60 > > Fixes: 0e89640b640d ("crypto: arm64 - Use modern annotations for assembly functions") > Signed-off-by: Jeremy Linton <jeremy.linton@arm.com> Reviewed-by: Ard Biesheuvel <ardb@kernel.org> > --- > arch/arm64/crypto/aes-neonbs-core.S | 4 ++-- > 1 file changed, 2 insertions(+), 2 deletions(-) > > diff --git a/arch/arm64/crypto/aes-neonbs-core.S b/arch/arm64/crypto/aes-neonbs-core.S > index b357164379f6..63a52ad9a75c 100644 > --- a/arch/arm64/crypto/aes-neonbs-core.S > +++ b/arch/arm64/crypto/aes-neonbs-core.S > @@ -788,7 +788,7 @@ SYM_FUNC_START_LOCAL(__xts_crypt8) > > 0: mov bskey, x21 > mov rounds, x22 > - br x7 > + br x16 > SYM_FUNC_END(__xts_crypt8) > > .macro __xts_crypt, do8, o0, o1, o2, o3, o4, o5, o6, o7 > @@ -806,7 +806,7 @@ SYM_FUNC_END(__xts_crypt8) > uzp1 v30.4s, v30.4s, v25.4s > ld1 {v25.16b}, [x24] > > -99: adr x7, \do8 > +99: adr x16, \do8 > bl __xts_crypt8 > > ldp q16, q17, [sp, #.Lframe_local_offset] > -- > 2.25.4 >
On Tue, Oct 06, 2020 at 11:33:26AM -0500, Jeremy Linton wrote: > The AES code uses a 'br x7' as part of a function called by > a macro. That branch needs a bti_j as a target. This results > in a panic as seen below. Using x16 (or x17) with an indirect > branch keeps the target bti_c. Reviewed-by: Mark Brown <broonie@kernel.org>
On Tue, Oct 06, 2020 at 11:33:26AM -0500, Jeremy Linton wrote: > The AES code uses a 'br x7' as part of a function called by > a macro. That branch needs a bti_j as a target. This results > in a panic as seen below. Using x16 (or x17) with an indirect > branch keeps the target bti_c. > > Bad mode in Synchronous Abort handler detected on CPU1, code 0x34000003 -- BTI > CPU: 1 PID: 265 Comm: cryptomgr_test Not tainted 5.8.11-300.fc33.aarch64 #1 > pstate: 20400c05 (nzCv daif +PAN -UAO BTYPE=j-) > pc : aesbs_encrypt8+0x0/0x5f0 [aes_neon_bs] > lr : aesbs_xts_encrypt+0x48/0xe0 [aes_neon_bs] > sp : ffff80001052b730 > > aesbs_encrypt8+0x0/0x5f0 [aes_neon_bs] > __xts_crypt+0xb0/0x2dc [aes_neon_bs] > xts_encrypt+0x28/0x3c [aes_neon_bs] > crypto_skcipher_encrypt+0x50/0x84 > simd_skcipher_encrypt+0xc8/0xe0 > crypto_skcipher_encrypt+0x50/0x84 > test_skcipher_vec_cfg+0x224/0x5f0 > test_skcipher+0xbc/0x120 > alg_test_skcipher+0xa0/0x1b0 > alg_test+0x3dc/0x47c > cryptomgr_test+0x38/0x60 > > Fixes: 0e89640b640d ("crypto: arm64 - Use modern annotations for assembly functions") > Signed-off-by: Jeremy Linton <jeremy.linton@arm.com> Reviewed-by: Dave Martin <Dave.Martin@arm.com> Note, if we ended up with any veneered function calls in the mix while x16 is live, this register could get clobbered. Given the self-contained nature of this code though, it seems highly unlikely that we will ever have multiple code sections of external calls here. Cheers ---Dave > --- > arch/arm64/crypto/aes-neonbs-core.S | 4 ++-- > 1 file changed, 2 insertions(+), 2 deletions(-) > > diff --git a/arch/arm64/crypto/aes-neonbs-core.S b/arch/arm64/crypto/aes-neonbs-core.S > index b357164379f6..63a52ad9a75c 100644 > --- a/arch/arm64/crypto/aes-neonbs-core.S > +++ b/arch/arm64/crypto/aes-neonbs-core.S > @@ -788,7 +788,7 @@ SYM_FUNC_START_LOCAL(__xts_crypt8) > > 0: mov bskey, x21 > mov rounds, x22 > - br x7 > + br x16 > SYM_FUNC_END(__xts_crypt8) > > .macro __xts_crypt, do8, o0, o1, o2, o3, o4, o5, o6, o7 > @@ -806,7 +806,7 @@ SYM_FUNC_END(__xts_crypt8) > uzp1 v30.4s, v30.4s, v25.4s > ld1 {v25.16b}, [x24] > > -99: adr x7, \do8 > +99: adr x16, \do8 > bl __xts_crypt8 > > ldp q16, q17, [sp, #.Lframe_local_offset] > -- > 2.25.4 > > > _______________________________________________ > linux-arm-kernel mailing list > linux-arm-kernel@lists.infradead.org > http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
diff --git a/arch/arm64/crypto/aes-neonbs-core.S b/arch/arm64/crypto/aes-neonbs-core.S index b357164379f6..63a52ad9a75c 100644 --- a/arch/arm64/crypto/aes-neonbs-core.S +++ b/arch/arm64/crypto/aes-neonbs-core.S @@ -788,7 +788,7 @@ SYM_FUNC_START_LOCAL(__xts_crypt8) 0: mov bskey, x21 mov rounds, x22 - br x7 + br x16 SYM_FUNC_END(__xts_crypt8) .macro __xts_crypt, do8, o0, o1, o2, o3, o4, o5, o6, o7 @@ -806,7 +806,7 @@ SYM_FUNC_END(__xts_crypt8) uzp1 v30.4s, v30.4s, v25.4s ld1 {v25.16b}, [x24] -99: adr x7, \do8 +99: adr x16, \do8 bl __xts_crypt8 ldp q16, q17, [sp, #.Lframe_local_offset]
The AES code uses a 'br x7' as part of a function called by a macro. That branch needs a bti_j as a target. This results in a panic as seen below. Using x16 (or x17) with an indirect branch keeps the target bti_c. Bad mode in Synchronous Abort handler detected on CPU1, code 0x34000003 -- BTI CPU: 1 PID: 265 Comm: cryptomgr_test Not tainted 5.8.11-300.fc33.aarch64 #1 pstate: 20400c05 (nzCv daif +PAN -UAO BTYPE=j-) pc : aesbs_encrypt8+0x0/0x5f0 [aes_neon_bs] lr : aesbs_xts_encrypt+0x48/0xe0 [aes_neon_bs] sp : ffff80001052b730 aesbs_encrypt8+0x0/0x5f0 [aes_neon_bs] __xts_crypt+0xb0/0x2dc [aes_neon_bs] xts_encrypt+0x28/0x3c [aes_neon_bs] crypto_skcipher_encrypt+0x50/0x84 simd_skcipher_encrypt+0xc8/0xe0 crypto_skcipher_encrypt+0x50/0x84 test_skcipher_vec_cfg+0x224/0x5f0 test_skcipher+0xbc/0x120 alg_test_skcipher+0xa0/0x1b0 alg_test+0x3dc/0x47c cryptomgr_test+0x38/0x60 Fixes: 0e89640b640d ("crypto: arm64 - Use modern annotations for assembly functions") Signed-off-by: Jeremy Linton <jeremy.linton@arm.com> --- arch/arm64/crypto/aes-neonbs-core.S | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)