Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]
Groups > linux.kernel > #1260883
| From | Andy Lutomirski <luto@amacapital.net> |
|---|---|
| Newsgroups | linux.kernel |
| Subject | Re: Kernel 4.3 breaks security in systems using capabilities |
| Date | 2015-11-02 20:00 +0100 |
| Message-ID | <qqsuK-nX-7@gated-at.bofh.it> (permalink) |
| References | <qqrIn-7E-11@gated-at.bofh.it> <qqsbn-hk-3@gated-at.bofh.it> |
| Organization | linux.* mail to news gateway |
On Mon, Nov 2, 2015 at 10:38 AM, Richard Weinberger <richard.weinberger@gmail.com> wrote: > CC'ing patch authors. > > On Mon, Nov 2, 2015 at 7:06 PM, Klaus Ethgen <Klaus+lkml@ethgen.de> wrote: >> -----BEGIN PGP SIGNED MESSAGE----- >> Hash: SHA512 >> >> Hi, >> >> I read recently about patch 58319057b7847667f0c9585b9de0e8932b0fdb08 >> which made it into kernel 4.3 recently. And I have to say that I was >> shocked on how could such a patch that breaks normal use of capabilities >> make it into the kernel. >> >> Usually I have set very own crafted capabilities set to files instead of >> having them SUID root. With that, I have a comparable set of inheritable >> capabilities set for limited users. That allows me to nearly drop all >> SUID binaries and replace it by only giving the processes the >> capabilities they need but only if the users are allowed to act with >> that capabilities. Especially, and that is important, it inhibit any >> leak of rights to any forked process, be it indented or by a security >> problem of the binary. >> >> With the patch above, any process that is spawned by such a program will >> inherit the raised capabilities if it has no own filecapabilities set. >> Even worse, even every user made tool can be target for such >> escalations! That drives the benefits in security of capabilities over >> SUID ad-absurdum. Can you describe what it is that you think changed in 4.3 that breaks anything? The behavior of inheritable capabilities shouldn't have changed. >> >> Let me add here, that I disagree with Andy Lutomirski about the >> usefulness of capability inheritance in kernels before that patch. They >> was fully usefull to only allow selective capabilities if both, the >> binary and the user was allowed to use it. I never want to have any >> capabilities for processes that I did not allow them to have. Even >> worse, I never want any capabilities allowed for any shell. It is >> horrible to even think about such a possibility!. >> >>> Users with nonzero pA are unlikely to unintentionally leak that >>> capability. If they run programs that try to drop privileges, dropping >>> privileges will still work. >> >> Even that is naiv. There are only few programs out there that do >> actively drop privileges. Most are agnostic about capabilities. But this >> crappy patch introduce a need for _every_ tool to drop all capabilities >> right after start to stay in a secure system. >> I don't know what you mean. Concrete examples are welcome. --Andy -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Back to linux.kernel | Previous | Next — Previous in thread | Next in thread | Find similar | Unroll thread
Kernel 4.3 breaks security in systems using capabilities Klaus Ethgen <Klaus+lkml@ethgen.de> - 2015-11-02 19:10 +0100
Re: Kernel 4.3 breaks security in systems using capabilities Richard Weinberger <richard.weinberger@gmail.com> - 2015-11-02 19:40 +0100
Re: Kernel 4.3 breaks security in systems using capabilities Andy Lutomirski <luto@amacapital.net> - 2015-11-02 20:00 +0100
Re: Kernel 4.3 breaks security in systems using capabilities Linus Torvalds <torvalds@linux-foundation.org> - 2015-11-02 20:00 +0100
Re: [KERNEL] Re: Kernel 4.3 breaks security in systems using capabilities Klaus Ethgen <Klaus+lkml@ethgen.de> - 2015-11-02 20:20 +0100
Re: [KERNEL] Re: Kernel 4.3 breaks security in systems using capabilities Andy Lutomirski <luto@amacapital.net> - 2015-11-02 20:50 +0100
Re: [KERNEL] Re: [KERNEL] Re: Kernel 4.3 breaks security in systems using capabilities Klaus Ethgen <Klaus+lkml@ethgen.de> - 2015-11-05 11:30 +0100
Re: [KERNEL] Re: [KERNEL] Re: Kernel 4.3 breaks security in systems using capabilities "Serge E. Hallyn" <serge@hallyn.com> - 2015-11-05 17:20 +0100
Re: [KERNEL] Re: [KERNEL] Re: [KERNEL] Re: Kernel 4.3 breaks security in systems using capabilities Klaus Ethgen <Klaus+lkml@ethgen.de> - 2015-11-05 18:20 +0100
Re: [KERNEL] Re: [KERNEL] Re: [KERNEL] Re: Kernel 4.3 breaks security in systems using capabilities "Serge E. Hallyn" <serge@hallyn.com> - 2015-11-05 18:40 +0100
Re: [KERNEL] Re: [KERNEL] Re: [KERNEL] Re: [KERNEL] Re: Kernel 4.3 breaks security in systems using capabilities Klaus Ethgen <Klaus+lkml@ethgen.de> - 2015-11-05 18:50 +0100
Re: [KERNEL] Re: [KERNEL] Re: [KERNEL] Re: [KERNEL] Re: Kernel 4.3 breaks security in systems using capabilities Andy Lutomirski <luto@amacapital.net> - 2015-11-05 20:10 +0100
Re: [KERNEL] Re: [KERNEL] Re: [KERNEL] Re: [KERNEL] Re: Kernel 4.3 breaks security in systems using capabilities "Serge E. Hallyn" <serge@hallyn.com> - 2015-11-05 23:10 +0100
Re: [KERNEL] Re: [KERNEL] Re: [KERNEL] Re: [KERNEL] Re: [KERNEL] Re: Kernel 4.3 breaks security in systems using capabilities Klaus Ethgen <Klaus+lkml@ethgen.de> - 2015-11-06 15:00 +0100
Re: [KERNEL] Re: [KERNEL] Re: [KERNEL] Re: [KERNEL] Re: [KERNEL] Re: Kernel 4.3 breaks security in systems using capabilities Theodore Ts'o <tytso@mit.edu> - 2015-11-06 17:00 +0100
Re: [KERNEL] Re: [KERNEL] Re: [KERNEL] Re: [KERNEL] Re: [KERNEL] Re: Kernel 4.3 breaks security in systems using capabilities Andy Lutomirski <luto@amacapital.net> - 2015-11-06 18:20 +0100
Re: [KERNEL] Re: [KERNEL] Re: [KERNEL] Re: [KERNEL] Re: [KERNEL] Re: Kernel 4.3 breaks security in systems using capabilities Casey Schaufler <casey@schaufler-ca.com> - 2015-11-06 19:00 +0100
Re: [KERNEL] Re: [KERNEL] Re: [KERNEL] Re: [KERNEL] Re: [KERNEL] Re: Kernel 4.3 breaks security in systems using capabilities "Serge E. Hallyn" <serge@hallyn.com> - 2015-11-06 19:10 +0100
Re: [KERNEL] Re: [KERNEL] Re: [KERNEL] Re: [KERNEL] Re: [KERNEL] Re: [KERNEL] Re: Kernel 4.3 breaks security in systems using capabilities Klaus Ethgen <Klaus+lkml@ethgen.de> - 2015-11-06 19:00 +0100
Re: [KERNEL] Re: [KERNEL] Re: [KERNEL] Re: [KERNEL] Re: [KERNEL] Re: [KERNEL] Re: Kernel 4.3 breaks security in systems using capabilities "Serge E. Hallyn" <serge@hallyn.com> - 2015-11-06 19:20 +0100
Re: [KERNEL] Re: [KERNEL] Re: [KERNEL] Re: [KERNEL] Re: [KERNEL] Re: [KERNEL] Re: [KERNEL] Re: Kernel 4.3 breaks security in systems using capabilities Klaus Ethgen <Klaus+lkml@ethgen.de> - 2015-11-07 12:10 +0100
Re: [KERNEL] Re: [KERNEL] Re: [KERNEL] Re: [KERNEL] Re: [KERNEL] Re: [KERNEL] Re: [KERNEL] Re: Kernel 4.3 breaks security in systems using capabilities "Serge E. Hallyn" <serge@hallyn.com> - 2015-11-08 18:10 +0100
Re: Kernel 4.3 breaks security in systems using capabilities Austin S Hemmelgarn <ahferroin7@gmail.com> - 2015-11-09 17:40 +0100
Re: [KERNEL] Re: Kernel 4.3 breaks security in systems using capabilities Klaus Ethgen <Klaus+lkml@ethgen.de> - 2015-11-09 18:30 +0100
Re: [KERNEL] Re: Kernel 4.3 breaks security in systems using capabilities Austin S Hemmelgarn <ahferroin7@gmail.com> - 2015-11-09 20:10 +0100
Re: [KERNEL] Re: [KERNEL] Re: Kernel 4.3 breaks security in systems using capabilities Klaus Ethgen <Klaus+lkml@ethgen.de> - 2015-11-09 22:30 +0100
Re: [KERNEL] Re: [KERNEL] Re: Kernel 4.3 breaks security in systems using capabilities Andy Lutomirski <luto@amacapital.net> - 2015-11-10 01:10 +0100
Re: [KERNEL] Re: [KERNEL] Re: [KERNEL] Re: Kernel 4.3 breaks security in systems using capabilities Klaus Ethgen <Klaus+lkml@ethgen.de> - 2015-11-10 13:00 +0100
Re: [KERNEL] Re: [KERNEL] Re: [KERNEL] Re: Kernel 4.3 breaks security in systems using capabilities Theodore Ts'o <tytso@mit.edu> - 2015-11-10 13:50 +0100
Re: [KERNEL] [PATCH] Kernel 4.3 breaks security in systems using capabilities Klaus Ethgen <Klaus+lkml@ethgen.de> - 2015-11-10 14:20 +0100
Re: [KERNEL] [PATCH] Kernel 4.3 breaks security in systems using capabilities Austin S Hemmelgarn <ahferroin7@gmail.com> - 2015-11-10 14:40 +0100
Re: [KERNEL] Re: [KERNEL] [PATCH] Kernel 4.3 breaks security in systems using capabilities Klaus Ethgen <Klaus+lkml@ethgen.de> - 2015-11-10 19:10 +0100
Re: [KERNEL] Re: [KERNEL] [PATCH] Kernel 4.3 breaks security in systems using capabilities Austin S Hemmelgarn <ahferroin7@gmail.com> - 2015-11-10 21:50 +0100
Re: [KERNEL] Re: [KERNEL] [PATCH] Kernel 4.3 breaks security in systems using capabilities Klaus Ethgen <Klaus+lkml@ethgen.de> - 2015-11-10 14:50 +0100
Re: [KERNEL] [PATCH] Kernel 4.3 breaks security in systems using capabilities Theodore Ts'o <tytso@mit.edu> - 2015-11-11 03:10 +0100
Re: [KERNEL] Re: [KERNEL] [PATCH] Kernel 4.3 breaks security in systems using capabilities Klaus Ethgen <Klaus+lkml@ethgen.de> - 2015-11-11 11:20 +0100
Re: [KERNEL] Re: [KERNEL] [PATCH] Kernel 4.3 breaks security in systems using capabilities Theodore Ts'o <tytso@mit.edu> - 2015-11-11 12:00 +0100
Re: [KERNEL] Re: [KERNEL] Re: [KERNEL] [PATCH] Kernel 4.3 breaks security in systems using capabilities Klaus Ethgen <Klaus+lkml@ethgen.de> - 2015-11-11 12:20 +0100
Re: [KERNEL] Re: [KERNEL] Re: [KERNEL] Re: Kernel 4.3 breaks security in systems using capabilities Christoph Lameter <cl@linux.com> - 2015-11-10 16:30 +0100
Re: [KERNEL] Re: [KERNEL] Re: Kernel 4.3 breaks security in systems using capabilities Andy Lutomirski <luto@amacapital.net> - 2015-11-05 17:30 +0100
Re: [KERNEL] Re: [KERNEL] Re: [KERNEL] Re: Kernel 4.3 breaks security in systems using capabilities Klaus Ethgen <Klaus+lkml@ethgen.de> - 2015-11-05 18:30 +0100
csiph-web