From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Google-Smtp-Source: AH8x224Q/iYQPA6AbPMMoNxneRNPZt4OV7LENAZ1ZTWHSUqFkEMBO3Zt6arYoCPFpxK7r3mGMseG ARC-Seal: i=1; a=rsa-sha256; t=1517591688; cv=none; d=google.com; s=arc-20160816; b=h0iOL/q3js9oQJ/vb2HAZNCr4oApXckikgbcXoma16P2oN8b/drJK1Ok/2t64hYKAE qC+U/BOdqGjL8hXyA84df/ZZISX1j+S0psL/Epma661crbR73M8rr1hZi5WdpEaFevgu A5Od7ChFb+eMZf9MrESYKJtszrBpdUvgE+gwogxIKuQYyyOqLdUkEPhvHVuGn14xUhkS G7TUIy/0CNtKgJiAi9GFRViuD5bcRL/P/oznrYaSCZgtUh1Cb2dPkYZcrcewrPE80fvg T8gktaAjuNDb4kvXnSToAydgd0466HZrzJjxQfQOXGVMePpPhyzeXjEZayvriW8CR1/+ 518w== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=mime-version:user-agent:references:in-reply-to:message-id:date :subject:cc:to:from:arc-authentication-results; bh=xrC0eCsltUcbw1/wT6IxgawhbM2eC4zqHXkSzInmoz0=; b=y08YBp+0+thD2h5mOhv2UuAGVoet1e06ZOaZ/BJYy3Nwc0/dsvjQkkka42dERfQdq4 klftdAhARiEhAZbnbdUUQ/vCVlh3hy2KaLyj7kB5K5k8LOBjeLHBU1mfGShHKEQ4Wf2q RZ2ah41pyMDR4RGEsIVK7+Pb7DD2J5c3RKcQvTW6+URGw2fE7LBRDpvrFepfzgn66/K2 rLfmqvWTGBg0yI8JRwPDsMbA5ItZdOccEP8HRSynp7hLPNCImXLns1wLAoVoXYPzbGJZ g8EfryTdL9mDSy3k1usw7mHyO4M1jNfa3cR6Zhi+184VZaT79/witsKB5fwmppZY2tgL nl+Q== ARC-Authentication-Results: i=1; mx.google.com; spf=softfail (google.com: domain of transitioning gregkh@linuxfoundation.org does not designate 90.92.71.90 as permitted sender) smtp.mailfrom=gregkh@linuxfoundation.org Authentication-Results: mx.google.com; spf=softfail (google.com: domain of transitioning gregkh@linuxfoundation.org does not designate 90.92.71.90 as permitted sender) smtp.mailfrom=gregkh@linuxfoundation.org From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Junaid Shahid , Herbert Xu Subject: [PATCH 4.15 10/55] crypto: aesni - Fix out-of-bounds access of the data buffer in generic-gcm-aesni Date: Fri, 2 Feb 2018 17:58:28 +0100 Message-Id: <20180202140826.954760210@linuxfoundation.org> X-Mailer: git-send-email 2.16.1 In-Reply-To: <20180202140826.117602411@linuxfoundation.org> References: <20180202140826.117602411@linuxfoundation.org> User-Agent: quilt/0.65 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 X-getmail-retrieved-from-mailbox: INBOX X-GMAIL-LABELS: =?utf-8?b?IlxcU2VudCI=?= X-GMAIL-THRID: =?utf-8?q?1591309756503641082?= X-GMAIL-MSGID: =?utf-8?q?1591310222234827397?= X-Mailing-List: linux-kernel@vger.kernel.org List-ID: 4.15-stable review patch. If anyone has any objections, please let me know. ------------------ From: Junaid Shahid commit b20209c91e23a9bbad9cac2f80bc16b3c259e10e upstream. The aesni_gcm_enc/dec functions can access memory before the start of the data buffer if the length of the data buffer is less than 16 bytes. This is because they perform the read via a single 16-byte load. This can potentially result in accessing a page that is not mapped and thus causing the machine to crash. This patch fixes that by reading the partial block byte-by-byte and optionally an via 8-byte load if the block was at least 8 bytes. Fixes: 0487ccac ("crypto: aesni - make non-AVX AES-GCM work with any aadlen") Signed-off-by: Junaid Shahid Signed-off-by: Herbert Xu Signed-off-by: Greg Kroah-Hartman --- arch/x86/crypto/aesni-intel_asm.S | 87 +++++++++++++++++++------------------- 1 file changed, 45 insertions(+), 42 deletions(-) --- a/arch/x86/crypto/aesni-intel_asm.S +++ b/arch/x86/crypto/aesni-intel_asm.S @@ -257,6 +257,37 @@ aad_shift_arr: pxor \TMP1, \GH # result is in TMP1 .endm +# Reads DLEN bytes starting at DPTR and stores in XMMDst +# where 0 < DLEN < 16 +# Clobbers %rax, DLEN and XMM1 +.macro READ_PARTIAL_BLOCK DPTR DLEN XMM1 XMMDst + cmp $8, \DLEN + jl _read_lt8_\@ + mov (\DPTR), %rax + MOVQ_R64_XMM %rax, \XMMDst + sub $8, \DLEN + jz _done_read_partial_block_\@ + xor %eax, %eax +_read_next_byte_\@: + shl $8, %rax + mov 7(\DPTR, \DLEN, 1), %al + dec \DLEN + jnz _read_next_byte_\@ + MOVQ_R64_XMM %rax, \XMM1 + pslldq $8, \XMM1 + por \XMM1, \XMMDst + jmp _done_read_partial_block_\@ +_read_lt8_\@: + xor %eax, %eax +_read_next_byte_lt8_\@: + shl $8, %rax + mov -1(\DPTR, \DLEN, 1), %al + dec \DLEN + jnz _read_next_byte_lt8_\@ + MOVQ_R64_XMM %rax, \XMMDst +_done_read_partial_block_\@: +.endm + /* * if a = number of total plaintext bytes * b = floor(a/16) @@ -1386,14 +1417,6 @@ _esb_loop_\@: * * AAD Format with 64-bit Extended Sequence Number * -* aadLen: -* from the definition of the spec, aadLen can only be 8 or 12 bytes. -* The code supports 16 too but for other sizes, the code will fail. -* -* TLen: -* from the definition of the spec, TLen can only be 8, 12 or 16 bytes. -* For other sizes, the code will fail. -* * poly = x^128 + x^127 + x^126 + x^121 + 1 * *****************************************************************************/ @@ -1487,19 +1510,16 @@ _zero_cipher_left_decrypt: PSHUFB_XMM %xmm10, %xmm0 ENCRYPT_SINGLE_BLOCK %xmm0, %xmm1 # E(K, Yn) - sub $16, %r11 - add %r13, %r11 - movdqu (%arg3,%r11,1), %xmm1 # receive the last <16 byte block - lea SHIFT_MASK+16(%rip), %r12 - sub %r13, %r12 -# adjust the shuffle mask pointer to be able to shift 16-%r13 bytes -# (%r13 is the number of bytes in plaintext mod 16) - movdqu (%r12), %xmm2 # get the appropriate shuffle mask - PSHUFB_XMM %xmm2, %xmm1 # right shift 16-%r13 butes + lea (%arg3,%r11,1), %r10 + mov %r13, %r12 + READ_PARTIAL_BLOCK %r10 %r12 %xmm2 %xmm1 + + lea ALL_F+16(%rip), %r12 + sub %r13, %r12 movdqa %xmm1, %xmm2 pxor %xmm1, %xmm0 # Ciphertext XOR E(K, Yn) - movdqu ALL_F-SHIFT_MASK(%r12), %xmm1 + movdqu (%r12), %xmm1 # get the appropriate mask to mask out top 16-%r13 bytes of %xmm0 pand %xmm1, %xmm0 # mask out top 16-%r13 bytes of %xmm0 pand %xmm1, %xmm2 @@ -1508,9 +1528,6 @@ _zero_cipher_left_decrypt: pxor %xmm2, %xmm8 GHASH_MUL %xmm8, %xmm13, %xmm9, %xmm10, %xmm11, %xmm5, %xmm6 - # GHASH computation for the last <16 byte block - sub %r13, %r11 - add $16, %r11 # output %r13 bytes MOVQ_R64_XMM %xmm0, %rax @@ -1664,14 +1681,6 @@ ENDPROC(aesni_gcm_dec) * * AAD Format with 64-bit Extended Sequence Number * -* aadLen: -* from the definition of the spec, aadLen can only be 8 or 12 bytes. -* The code supports 16 too but for other sizes, the code will fail. -* -* TLen: -* from the definition of the spec, TLen can only be 8, 12 or 16 bytes. -* For other sizes, the code will fail. -* * poly = x^128 + x^127 + x^126 + x^121 + 1 ***************************************************************************/ ENTRY(aesni_gcm_enc) @@ -1764,19 +1773,16 @@ _zero_cipher_left_encrypt: movdqa SHUF_MASK(%rip), %xmm10 PSHUFB_XMM %xmm10, %xmm0 - ENCRYPT_SINGLE_BLOCK %xmm0, %xmm1 # Encrypt(K, Yn) - sub $16, %r11 - add %r13, %r11 - movdqu (%arg3,%r11,1), %xmm1 # receive the last <16 byte blocks - lea SHIFT_MASK+16(%rip), %r12 + + lea (%arg3,%r11,1), %r10 + mov %r13, %r12 + READ_PARTIAL_BLOCK %r10 %r12 %xmm2 %xmm1 + + lea ALL_F+16(%rip), %r12 sub %r13, %r12 - # adjust the shuffle mask pointer to be able to shift 16-r13 bytes - # (%r13 is the number of bytes in plaintext mod 16) - movdqu (%r12), %xmm2 # get the appropriate shuffle mask - PSHUFB_XMM %xmm2, %xmm1 # shift right 16-r13 byte pxor %xmm1, %xmm0 # Plaintext XOR Encrypt(K, Yn) - movdqu ALL_F-SHIFT_MASK(%r12), %xmm1 + movdqu (%r12), %xmm1 # get the appropriate mask to mask out top 16-r13 bytes of xmm0 pand %xmm1, %xmm0 # mask out top 16-r13 bytes of xmm0 movdqa SHUF_MASK(%rip), %xmm10 @@ -1785,9 +1791,6 @@ _zero_cipher_left_encrypt: pxor %xmm0, %xmm8 GHASH_MUL %xmm8, %xmm13, %xmm9, %xmm10, %xmm11, %xmm5, %xmm6 # GHASH computation for the last <16 byte block - sub %r13, %r11 - add $16, %r11 - movdqa SHUF_MASK(%rip), %xmm10 PSHUFB_XMM %xmm10, %xmm0