dnscrypt-proxy: dnscrypt-proxy v2.0.10 crash on Alpine linux v3.7.0 x86

Hello:

Thank you for your work.

Here is the core dump from dnscrypt-proxy v2.0.10 under Alpine linux v3.7.0-(grsecurity hardened), x86.

[2018-04-25 15:00:11] [NOTICE] dnscrypt-proxy is ready - live servers: 32
unexpected fault address 0x34846000
fatal error: fault
[signal SIGSEGV: segmentation violation code=0x2 addr=0x34846000 pc=0x16c985c2]

goroutine 64 [running]:
runtime.throw(0x16ec4ea1, 0x5)
	/usr/lib/go/src/runtime/panic.go:616 +0x77 fp=0x34405c10 sp=0x34405c04 pc=0x16b50ef7
runtime.sigpanic()
	/usr/lib/go/src/runtime/signal_unix.go:395 +0x1e4 fp=0x34405c34 sp=0x34405c10 pc=0x16b668c4
github.com/aead/chacha20/chacha.xorKeyStreamSSE2(0x34405d34, 0x40, 0x40, 0x34405d34, 0x40, 0x40, 0x34388040, 0x34388000, 0x14, 0x16c97555)
	/home/buildozer/aports/community/dnscrypt-proxy/src/dnscrypt-proxy-2.0.10/src/github.com/aead/chacha20/chacha/chacha_386.s:157 +0x162 fp=0x34405c38 sp=0x34405c34 pc=0x16c985c2
github.com/aead/chacha20/chacha.xorKeyStream(0x34405d34, 0x40, 0x40, 0x34405d34, 0x40, 0x40, 0x34388040, 0x34388000, 0x14, 0x20)
	/home/buildozer/aports/community/dnscrypt-proxy/src/dnscrypt-proxy-2.0.10/src/github.com/aead/chacha20/chacha/chacha_386.go:65 +0x8e fp=0x34405c64 sp=0x34405c38 pc=0x16c975de
github.com/aead/chacha20/chacha.(*Cipher).XORKeyStream(0x34388000, 0x34405d34, 0x40, 0x40, 0x34405d34, 0x40, 0x40)
	/home/buildozer/aports/community/dnscrypt-proxy/src/dnscrypt-proxy-2.0.10/src/github.com/aead/chacha20/chacha/chacha.go:165 +0x1b3 fp=0x34405ca0 sp=0x34405c64 pc=0x16c97233
runtime: unexpected return pc for github.com/jedisct1/xsecretbox.Seal called from 0x8f1f4b36
stack: frame={sp:0x34405ca0, fp:0x34405d90} stack=[0x34405000,0x34406000)
34405c20:  34846000  34247ce0  16b7a981 <runtime.morestack+65>  16b666e5 <runtime.sigpanic+5> 
34405c30:  16c985c2 <github.com/aead/chacha20/chacha.xorKeyStreamSSE2+354>  16c975de <github.com/aead/chacha20/chacha.xorKeyStream+142>  34405d34  00000040 
34405c40:  00000040  34405d34  00000040  00000040 
34405c50:  34388040  34388000  00000014  16c97555 <github.com/aead/chacha20/chacha.xorKeyStream+5> 
34405c60:  16c97233 <github.com/aead/chacha20/chacha.(*Cipher).XORKeyStream+435>  34405d34  00000040  00000040 
34405c70:  34405d34  00000040  00000040  34388040 
34405c80:  34388000  00000014  00000020  00000020 
34405c90:  00000000  00000000  16c97085 <github.com/aead/chacha20/chacha.(*Cipher).XORKeyStream+5>  16ca06e8 <github.com/jedisct1/xsecretbox.Seal+216> 
34405ca0: <34388000  34405d34  00000040  00000040 
34405cb0:  34405d34  00000040  00000040  34388000 
34405cc0:  00000000  00000000  16b77b60 <runtime.(*mcache).nextFree.func1+0>  24006000 
34405cd0:  16b3deb5 <runtime.gcTrigger.test+5>  16b35d64 <runtime.mallocgc+948>  00000001  00000000 
34405ce0:  00000000  00000000  00000000  01014304 
34405cf0:  00000000  00000500  00000002  3459e000 
34405d00:  172235e0  00000000  00004000  34277680 
34405d10:  24006000  00000000  00000060  342608f0 
34405d20:  343723c0  16b7cc11 <runtime.memclrNoHeapPointers+65>  16b67cf7 <runtime.growslice+519>  3459e281 
34405d30:  0000027f  799b09b3  476476e4  ad4a01ac 
34405d40:  a3add054  94aee6ed  85cd259d  949fb27a 
34405d50:  b3a691f3  6dc28ba2  982bd4a0  ad57b292 
34405d60:  767d8824  63c5ec33  e796424c  04ea8fe5 
34405d70:  4f76766f  d6e51325  255a730e  fb3dd7d5 
34405d80:  f6612be9  f82eaff2  ed85cf31 !8f1f4b36 
34405d90: >e035f845  d0ec3743  669815bf  33bcad34 
34405da0:  8cf9ac4a  e82a4ccf  0313d34d  2b227014 
34405db0:  8b668a36  68e7beaf  b8797db0  e9a064f5 
34405dc0:  d51853e4  1a2d2a22  78155d31  06ae1b93 
34405dd0:  792b1791  352f22d7  e64a17e7  75076b81 
34405de0:  1a666551  722ff12f  8cc86c83  1699194a 
34405df0:  a213dca6  16fe22aa  6c8f8ad2  dd88f8b2 
34405e00:  fffe84bd  72d8df77  e99459f9  13b0478a 
github.com/jedisct1/xsecretbox.Seal(0xe035f845, 0xd0ec3743, 0x669815bf, 0x33bcad34, 0x8cf9ac4a, 0xe82a4ccf, 0x313d34d, 0x2b227014, 0x8b668a36, 0x68e7beaf, ...)
	/home/buildozer/aports/community/dnscrypt-proxy/src/dnscrypt-proxy-2.0.10/src/github.com/jedisct1/xsecretbox/xsecretbox.go:31 +0xd8 fp=0x34405d90 sp=0x34405ca0 pc=0x16ca06e8
created by main.(*Proxy).udpListener
	/home/buildozer/aports/community/dnscrypt-proxy/src/dnscrypt-proxy-2.0.10/dnscrypt-proxy/proxy.go:141 +0x88

thank you

west suhanic

About this issue

Original URL
State: closed
Created 6 years ago
Comments: 41 (30 by maintainers)

Commits related to this issue

replace unsigned jump instruction JB(E) with signed JL(E) This commit replaces the unsigned jump instructions JB and JBE with signed jump instructions JL / JLE. The length of a slice in Go is defined... — committed to aead/chacha20 by deleted user 6 years ago
replace unsigned jump JA with signed jump JG This commit replaces the jump if above JA (unsigned) with jump if greater JG (signed) if the asm code compares the length of slice. The length of a slice ... — committed to aead/chacha20 by deleted user 6 years ago
replace unsigned jump instruction JB(E) with signed JL(E) This commit replaces the unsigned jump instructions JB and JBE with signed jump instructions JL / JLE. The length of a slice in Go is defined... — committed to aead/chacha20 by deleted user 6 years ago
replace unsigned jump JA with signed jump JG This commit replaces the jump if above JA (unsigned) with jump if greater JG (signed) if the asm code compares the length of slice. The length of a slice ... — committed to aead/chacha20 by deleted user 6 years ago
replace unsigned jump JA with signed jump JG This commit replaces the jump if above JA (unsigned) with jump if greater JG (signed) if the asm code compares the length of slice. The length of a slice ... — committed to aead/chacha20 by deleted user 6 years ago
replace unsigned jump instruction JB(E) with signed JL(E) This commit replaces the unsigned jump instructions JB and JBE with signed jump instructions JL / JLE. The length of a slice in Go is defined... — committed to aead/chacha20 by deleted user 6 years ago
replace unsigned jump JA with signed jump JG This commit replaces the jump if above JA (unsigned) with jump if greater JG (signed) if the asm code compares the length of slice. The length of a slice ... — committed to aead/chacha20 by deleted user 6 years ago

Most upvoted comments

@jedisct1 The only thing I can think of that may cause this is issue is a unsigned comparison. The 386 code compares the length of the slice using JB (jump if below (unsigned)). I change it to JL (jump if less (signed)). Both versions work well on amd64 and amd64 running in 386 comp. mode. I’ve build dnscrypto-proxy with this change for linux_386.

@westsuhanic It would be great if you can try out the custom release. If this doesn’t fix the issue, I’ll disable 386 assembly until I can reproduce and investigate it properly.

aead on Apr 25, 2018

Good to know that at least it’s always gonna be CX.

jedisct1 on Apr 26, 2018

Thanks for merging this, @aead.

Time to tag a new release, then.

jedisct1 on Apr 26, 2018

Hello Everyone:

I have tried the custom release on my x86 hardware and it works. I am testing repeatedly using, for example:

sudo ./dnscrypt-proxy -resolve ibm.fr

Running the above command against dnscrypt-proxy v2.0.10-r0 from edge/community would core every time.

What was changed in order to get this to work? Is there anything else I can try? How does this custom release make it into the apk repository?

thank you,

west suhanic

On Wed, Apr 25, 2018 at 2:30 PM, Andreas Auernhammer < notifications@github.com> wrote:

@jedisct1 https://github.com/jedisct1 The only thing I can think of that may cause this is issue is a unsigned comparison. The 386 code compares the length of the slice using JB (jump if below (unsigned)). I change it to JL (jump if less (signed)). Both versions work well on amd64 and amd64 running in 386 comp. mode. I’ve build dnscrypto-proxy with this change for linux_386.

@westsuhanic https://github.com/westsuhanic It would be great if you can try out the custom release https://github.com/aead/dnscrypt-proxy/releases/download/2.0.11/dnscrypt-proxy-linux_i386-2.0.11.tar.gz. If this doesn’t fix the issue, I’ll disable 386 assembly until I can reproduce and investigate it properly.

— You are receiving this because you were mentioned. Reply to this email directly, view it on GitHub https://github.com/jedisct1/dnscrypt-proxy/issues/404#issuecomment-384388678, or mute the thread https://github.com/notifications/unsubscribe-auth/AbU48xoe_qYVDWL_i-7wMIM3NRai9jMlks5tsMC2gaJpZM4Tjngp .

westsuhanic on Apr 26, 2018

Tried the tar from your last post on 32bit VM. That’s working too

ianbashford on Apr 25, 2018

The vm is x86_64. Ran the i386 binary as you described and responds fine. One minor adjustment I made to the config was to listen on listen_addresses = [‘:53’]

Hope that’s an OK mod that doesn’t invalidate the test…

ianbashford on Apr 25, 2018