On 26 July 2014 17:31, Mikulas Patocka <mpatocka@xxxxxxxxxx> wrote: > > > On Sat, 26 Jul 2014, Ard Biesheuvel wrote: > >> On 26 July 2014 15:13, Ard Biesheuvel <ard.biesheuvel@xxxxxxxxxx> wrote: >> > On 26 July 2014 01:40, Mikulas Patocka <mpatocka@xxxxxxxxxx> wrote: >> >> cryptsetup fails on arm64 when using kernel encryption via AF_ALG socket. >> >> See https://bugzilla.redhat.com/show_bug.cgi?id=1122937 >> >> >> >> The bug is caused by incorrect handling of unaligned data in >> >> arch/arm64/crypto/aes-glue.c. Cryptsetup creates a buffer that is aligned >> >> on 8 bytes, but not on 16 bytes. It opens AF_ALG socket and uses the >> >> socket to encrypt data in the buffer. The arm64 crypto accelerator causes >> >> data corruption or crashes in the scatterwalk_pagedone. >> >> >> >> This patch fixes the bug by passing the residue bytes that were not >> >> processed as the last parameter to blkcipher_walk_done. >> >> >> >> Signed-off-by: Mikulas Patocka <mpatocka@xxxxxxxxxx> >> >> >> > >> > Acked-by: Ard Biesheuvel <ard.biesheuvel@xxxxxxxxxx> >> > >> > Thanks for the patch. This correctly fixes a thinko on my part >> > regarding the guarantees offered by the blkcipher API. Unfortunately, >> > this wasn't caught by the tcrypt test suite, so I will propose some >> > patches later to address cases like this. >> > >> > BTW using kernel crypto with AF_ALG is fairly pointless when using >> > crypto instructions instead of crypto accelerator peripherals, should >> > we change anything on the kernel side so we don't expose these >> > drivers? > > The userspace library (gcrypt in this case) doesn't support ARM64, so it's > still better to call the kernel. > OK >> > @Catalin: this is a bug fix for the code that was merged this cycle. I >> > would recommend to merge this for 3.16, but if not, could you please >> > add a cc stable? Or ack it and perhaps Herbert can take both? (There >> > is a similar patch for ARM as well) >> > >> >> ... only this patch fails to repair the ECB case. >> @Mikulas: could you do a v2 and include ECB encryption/decryption? >> >> Cheers, >> Ard. > > The patch changes ecb_encrypt and ecb_decrypt just like cbc and xts > functions. What is the problem with ECB? > You are right, I got the patches mixed up (this one and the ARM one) Both look fine, and complete. -- Ard. >> >> Index: linux-3.16.0-0.rc6.git1.1.fc21.aarch64/arch/arm64/crypto/aes-glue.c >> >> =================================================================== >> >> --- linux-3.16.0-0.rc6.git1.1.fc21.aarch64.orig/arch/arm64/crypto/aes-glue.c >> >> +++ linux-3.16.0-0.rc6.git1.1.fc21.aarch64/arch/arm64/crypto/aes-glue.c >> >> @@ -106,7 +106,7 @@ static int ecb_encrypt(struct blkcipher_ >> >> for (first = 1; (blocks = (walk.nbytes / AES_BLOCK_SIZE)); first = 0) { >> >> aes_ecb_encrypt(walk.dst.virt.addr, walk.src.virt.addr, >> >> (u8 *)ctx->key_enc, rounds, blocks, first); >> >> - err = blkcipher_walk_done(desc, &walk, 0); >> >> + err = blkcipher_walk_done(desc, &walk, walk.nbytes % AES_BLOCK_SIZE); >> >> } >> >> kernel_neon_end(); >> >> return err; >> >> @@ -128,7 +128,7 @@ static int ecb_decrypt(struct blkcipher_ >> >> for (first = 1; (blocks = (walk.nbytes / AES_BLOCK_SIZE)); first = 0) { >> >> aes_ecb_decrypt(walk.dst.virt.addr, walk.src.virt.addr, >> >> (u8 *)ctx->key_dec, rounds, blocks, first); >> >> - err = blkcipher_walk_done(desc, &walk, 0); >> >> + err = blkcipher_walk_done(desc, &walk, walk.nbytes % AES_BLOCK_SIZE); >> >> } >> >> kernel_neon_end(); >> >> return err; >> >> @@ -151,7 +151,7 @@ static int cbc_encrypt(struct blkcipher_ >> >> aes_cbc_encrypt(walk.dst.virt.addr, walk.src.virt.addr, >> >> (u8 *)ctx->key_enc, rounds, blocks, walk.iv, >> >> first); >> >> - err = blkcipher_walk_done(desc, &walk, 0); >> >> + err = blkcipher_walk_done(desc, &walk, walk.nbytes % AES_BLOCK_SIZE); >> >> } >> >> kernel_neon_end(); >> >> return err; >> >> @@ -174,7 +174,7 @@ static int cbc_decrypt(struct blkcipher_ >> >> aes_cbc_decrypt(walk.dst.virt.addr, walk.src.virt.addr, >> >> (u8 *)ctx->key_dec, rounds, blocks, walk.iv, >> >> first); >> >> - err = blkcipher_walk_done(desc, &walk, 0); >> >> + err = blkcipher_walk_done(desc, &walk, walk.nbytes % AES_BLOCK_SIZE); >> >> } >> >> kernel_neon_end(); >> >> return err; >> >> @@ -243,7 +243,7 @@ static int xts_encrypt(struct blkcipher_ >> >> aes_xts_encrypt(walk.dst.virt.addr, walk.src.virt.addr, >> >> (u8 *)ctx->key1.key_enc, rounds, blocks, >> >> (u8 *)ctx->key2.key_enc, walk.iv, first); >> >> - err = blkcipher_walk_done(desc, &walk, 0); >> >> + err = blkcipher_walk_done(desc, &walk, walk.nbytes % AES_BLOCK_SIZE); >> >> } >> >> kernel_neon_end(); >> >> >> >> @@ -267,7 +267,7 @@ static int xts_decrypt(struct blkcipher_ >> >> aes_xts_decrypt(walk.dst.virt.addr, walk.src.virt.addr, >> >> (u8 *)ctx->key1.key_dec, rounds, blocks, >> >> (u8 *)ctx->key2.key_enc, walk.iv, first); >> >> - err = blkcipher_walk_done(desc, &walk, 0); >> >> + err = blkcipher_walk_done(desc, &walk, walk.nbytes % AES_BLOCK_SIZE); >> >> } >> >> kernel_neon_end(); >> >> >> -- dm-devel mailing list dm-devel@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/dm-devel
