Patch "crypto: x86/sha256-mb - fix panic due to unaligned access" has been added to the 4.9-stable tree

This is a note to let you know that I've just added the patch titled

crypto: x86/sha256-mb - fix panic due to unaligned access

to the 4.9-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
crypto-x86-sha256-mb-fix-panic-due-to-unaligned-access.patch
and it can be found in the queue-4.9 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree, please let <[email protected]> know about it.

From: Andrey Ryabinin <[email protected]>
Date: Mon, 16 Oct 2017 18:51:30 +0300
Subject: crypto: x86/sha256-mb - fix panic due to unaligned access

From: Andrey Ryabinin <[email protected]>

commit 5dfeaac15f2b1abb5a53c9146041c7235eb9aa04 upstream.

struct sha256_ctx_mgr allocated in sha256_mb_mod_init() via kzalloc() and later passed in sha256_mb_flusher_mgr_flush_avx2() function where instructions vmovdqa used to access the struct. vmovdqa requires 16-bytes aligned argument, but nothing guarantees that struct sha256_ctx_mgr will have that alignment. Unaligned vmovdqa will generate GP fault.

Fix this by replacing vmovdqa with vmovdqu which doesn't have alignment requirements.

---
 arch/x86/crypto/sha256-mb/sha256_mb_mgr_flush_avx2.S |   12 ++++++------
 1 file changed, 6 insertions(+), 6 deletions(-)

@@ -155,8 +155,8 @@ LABEL skip_ %I
 .endr
 
 	# Find min length
-	vmovdqa _lens+0*16(state), %xmm0
-	vmovdqa _lens+1*16(state), %xmm1
+	vmovdqu _lens+0*16(state), %xmm0
+	vmovdqu _lens+1*16(state), %xmm1
 
 	vpminud %xmm1, %xmm0, %xmm2		# xmm2 has {D,C,B,A}
 	vpalignr $8, %xmm2, %xmm3, %xmm3	# xmm3 has {x,x,D,C}

@@ -176,8 +176,8 @@ LABEL skip_ %I
 	vpsubd	%xmm2, %xmm0, %xmm0
 	vpsubd	%xmm2, %xmm1, %xmm1
 
-	vmovdqa	%xmm0, _lens+0*16(state)
-	vmovdqa	%xmm1, _lens+1*16(state)
+	vmovdqu	%xmm0, _lens+0*16(state)
+	vmovdqu	%xmm1, _lens+1*16(state)
 
 	# "state" and "args" are the same address, arg1
 	# len is arg2

@@ -234,8 +234,8 @@ ENTRY(sha256_mb_mgr_get_comp_job_avx2)
 	jc	.return_null
 
 	# Find min length
-	vmovdqa	_lens(state), %xmm0
-	vmovdqa	_lens+1*16(state), %xmm1
+	vmovdqu	_lens(state), %xmm0
+	vmovdqu	_lens+1*16(state), %xmm1
 
 	vpminud	%xmm1, %xmm0, %xmm2		# xmm2 has {D,C,B,A}
 	vpalignr $8, %xmm2, %xmm3, %xmm3	# xmm3 has {x,x,D,C}

Patches currently in stable-queue which might be from [email protected] are

queue-4.9/crypto-x86-sha256-mb-fix-panic-due-to-unaligned-access.patch queue-4.9/crypto-x86-sha1-mb-fix-panic-due-to-unaligned-access.patch