Thursday 21 February 2019

Finally it made it !

Hi folks !

Nicely, warmer weather is coming here in Dublin, making pull over wearing unnecessary :-)
These few days I have been updating my FreeBSD machine and was pleasantly surprised to see ASLR support had been added, all the work from HardenedBSD and other individuals in past years came to fruition in a way. Its usefulness had been the subject of controversy over the years, both for possible performance concerns and low outcome in term of security but this mitigation technique among the others is a must have so even if it appears way later than other oses, I am still happy whatsoever :-) So basically you can set it for 32 bits and or 64 bits which is necessary in case old binaries still need to run with fixed addresses. I have personally enabled only for 64 bits since 2 days and noticed no real performance drop while its shuffling shows up here. For example, as a test, I have been running a 64 bits and 32 bits version of the same basic executable which request few memory regions and the results speak by themselves ...

dragonflame% ./a.out 
0x804b7f000-0x804d91000 diff: 18446744073707380736
0x80ae51000-0x80bab1000 diff: 18446744073696575488
0x80c56c000-0x80d008000 diff: 18446744073698426880
0x80d9e2000-0x80e537000 diff: 18446744073697669120
0x80e740000-0x80f01c000 diff: 18446744073700261888
0x80f809000-0x80ff86000 diff: 18446744073701699584
0x810c09000-0x8118c8000 diff: 18446744073696186368
0x811e0f000-0x812c97000 diff: 18446744073694314496
0x812f52000-0x8135b6000 diff: 18446744073702850560
0x813904000-0x814258000 diff: 18446744073699770368
0x8148f0000-0x81491f000 diff: 18446744073709359104
0x81588c000-0x81634f000 diff: 18446744073698267136
0x816442000-0x816607000 diff: 18446744073707696128
0x8171f9000-0x817778000 diff: 18446744073703788544
0x818214000-0x818aee000 diff: 18446744073700270080
0x819882000-0x819999000 diff: 18446744073708408832
dragonflame% ./a.out
0x805315000-0x806129000 diff: 18446744073694789632
0x80caa8000-0x80d352000 diff: 18446744073700466688
0x80de53000-0x80e333000 diff: 18446744073704439808
0x80f302000-0x81008b000 diff: 18446744073695358976
0x8107c3000-0x810a24000 diff: 18446744073707057152
0x811a16000-0x8124e8000 diff: 18446744073698205696
0x8126f8000-0x813452000 diff: 18446744073695551488
0x81345f000-0x813bac000 diff: 18446744073701896192
0x814603000-0x814ac8000 diff: 18446744073704550400
0x815346000-0x81599c000 diff: 18446744073702907904
0x816740000-0x8176c9000 diff: 18446744073693261824
0x817748000-0x817af1000 diff: 18446744073705713664
0x8187d3000-0x819287000 diff: 18446744073698328576
0x819d87000-0x81a968000 diff: 18446744073697095680
0x81b784000-0x81b970000 diff: 18446744073707536384
0x81bd21000-0x81bdcf000 diff: 18446744073708838912
dragonflame% ./a32.out 
0x2064b000-0x2064c000 diff: 4294963200
0x20657000-0x20658000 diff: 4294963200
0x20659000-0x2065a000 diff: 4294963200
0x2065b000-0x2065c000 diff: 4294963200
0x2065d000-0x2065e000 diff: 4294963200
0x2065f000-0x20660000 diff: 4294963200
0x20661000-0x20662000 diff: 4294963200
0x20663000-0x20664000 diff: 4294963200
0x20665000-0x20666000 diff: 4294963200
0x20667000-0x20668000 diff: 4294963200
0x20669000-0x2066a000 diff: 4294963200
0x2066b000-0x2066c000 diff: 4294963200
0x2066d000-0x2066e000 diff: 4294963200
0x2066f000-0x20670000 diff: 4294963200
0x20671000-0x20672000 diff: 4294963200
0x20673000-0x20674000 diff: 4294963200
dragonflame% ./a32.out 
0x2064b000-0x2064c000 diff: 4294963200
0x20657000-0x20658000 diff: 4294963200
0x20659000-0x2065a000 diff: 4294963200
0x2065b000-0x2065c000 diff: 4294963200
0x2065d000-0x2065e000 diff: 4294963200
0x2065f000-0x20660000 diff: 4294963200
0x20661000-0x20662000 diff: 4294963200
0x20663000-0x20664000 diff: 4294963200
0x20665000-0x20666000 diff: 4294963200
0x20667000-0x20668000 diff: 4294963200
0x20669000-0x2066a000 diff: 4294963200
0x2066b000-0x2066c000 diff: 4294963200
0x2066d000-0x2066e000 diff: 4294963200
0x2066f000-0x20670000 diff: 4294963200
0x20671000-0x20672000 diff: 4294963200
0x20673000-0x20674000 diff: 4294963200


There will be probably further work until the 13th branch will be released however at the moment that is promising ... I ve been added this feature support in radare just yesterday.

In a previous post, I mentioned further FreeBSD support in PHP, so the network flags one had been now accepted and merged... Another one ought to be reviewed soon-ish bringing FreeBSD rfork call into that language ... About the video game Stalker, the second batch of changes for FreeBSD had been also accepted and merged, that was one of the most important parts, there should be more to come but not until other folks had merged their clang support basically because at the moment it needs gcc 7 or so but under FreeBSD the code generation crashes.

More important, next events this year ought to be AsiaBSDCon and BSDCan, hopefully will try to be present in one of those two :-)

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