Re: kasan behavior when built with unsupported compiler

On 03/09/2017 01:16 PM, Dmitry Vyukov wrote: > > Looking at this report I don't see how this is OOB. > Object starts at 0x88006a2255e0, object size is 69 bytes (from shadow). > 88006a22560e + 20 bytes is not OOB. > Indeed, perhaps gcc 4.7.4 miscompiles something check_memory_region ?

Re: kasan behavior when built with unsupported compiler

On 03/09/2017 01:16 PM, Dmitry Vyukov wrote: > > Looking at this report I don't see how this is OOB. > Object starts at 0x88006a2255e0, object size is 69 bytes (from shadow). > 88006a22560e + 20 bytes is not OOB. > Indeed, perhaps gcc 4.7.4 miscompiles something check_memory_region ?

Re: kasan behavior when built with unsupported compiler

On Thu, Mar 9, 2017 at 10:58 AM, Nikolay Borisov wrote: > > > On 9.03.2017 11:46, Andrey Ryabinin wrote: >> On 03/08/2017 11:10 AM, Nikolay Borisov wrote: >> >>> >>> So apparently this is indeed a false positive, resulting from using the old >>> compiler. I used the

Re: kasan behavior when built with unsupported compiler

On Thu, Mar 9, 2017 at 10:58 AM, Nikolay Borisov wrote: > > > On 9.03.2017 11:46, Andrey Ryabinin wrote: >> On 03/08/2017 11:10 AM, Nikolay Borisov wrote: >> >>> >>> So apparently this is indeed a false positive, resulting from using the old >>> compiler. I used the attached patch to verify it.

Re: kasan behavior when built with unsupported compiler

On 03/08/2017 11:10 AM, Nikolay Borisov wrote: > > So apparently this is indeed a false positive, resulting from using the old > compiler. I used the attached patch to verify it. > > And what it prints is : > [ 17.184288] Assigned fbdev-blacklist.conff(880001ea8020)20 whole > object:

Re: kasan behavior when built with unsupported compiler

On 03/08/2017 11:10 AM, Nikolay Borisov wrote: > > So apparently this is indeed a false positive, resulting from using the old > compiler. I used the attached patch to verify it. > > And what it prints is : > [ 17.184288] Assigned fbdev-blacklist.conff(880001ea8020)20 whole > object:

Re: kasan behavior when built with unsupported compiler

On 9.03.2017 11:46, Andrey Ryabinin wrote: > On 03/08/2017 11:10 AM, Nikolay Borisov wrote: > >> >> So apparently this is indeed a false positive, resulting from using the old >> compiler. I used the attached patch to verify it. >> >> And what it prints is : >> [ 17.184288] Assigned

Re: kasan behavior when built with unsupported compiler

On 9.03.2017 11:46, Andrey Ryabinin wrote: > On 03/08/2017 11:10 AM, Nikolay Borisov wrote: > >> >> So apparently this is indeed a false positive, resulting from using the old >> compiler. I used the attached patch to verify it. >> >> And what it prints is : >> [ 17.184288] Assigned

Re: kasan behavior when built with unsupported compiler

On Thu, Mar 9, 2017 at 10:46 AM, Andrey Ryabinin wrote: > On 03/08/2017 11:10 AM, Nikolay Borisov wrote: > >> >> So apparently this is indeed a false positive, resulting from using the old >> compiler. I used the attached patch to verify it. >> >> And what it prints is :

Re: kasan behavior when built with unsupported compiler

On Thu, Mar 9, 2017 at 10:46 AM, Andrey Ryabinin wrote: > On 03/08/2017 11:10 AM, Nikolay Borisov wrote: > >> >> So apparently this is indeed a false positive, resulting from using the old >> compiler. I used the attached patch to verify it. >> >> And what it prints is : >> [ 17.184288]

Re: kasan behavior when built with unsupported compiler

On Wed, Mar 8, 2017 at 9:10 AM, Nikolay Borisov wrote: > > > On 7.03.2017 17:54, Dmitry Vyukov wrote: >> On Tue, Mar 7, 2017 at 4:35 PM, Nikolay Borisov >> wrote: >>> Hello, >>> >>> I've been chasing a particular UAF as reported by kasan >>>

Re: kasan behavior when built with unsupported compiler

On Wed, Mar 8, 2017 at 9:10 AM, Nikolay Borisov wrote: > > > On 7.03.2017 17:54, Dmitry Vyukov wrote: >> On Tue, Mar 7, 2017 at 4:35 PM, Nikolay Borisov >> wrote: >>> Hello, >>> >>> I've been chasing a particular UAF as reported by kasan >>>

Re: kasan behavior when built with unsupported compiler

On 7.03.2017 17:54, Dmitry Vyukov wrote: > On Tue, Mar 7, 2017 at 4:35 PM, Nikolay Borisov > wrote: >> Hello, >> >> I've been chasing a particular UAF as reported by kasan >> (https://www.spinics.net/lists/kernel/msg2458136.html). However, one >> thing which I took

Re: kasan behavior when built with unsupported compiler

On 7.03.2017 17:54, Dmitry Vyukov wrote: > On Tue, Mar 7, 2017 at 4:35 PM, Nikolay Borisov > wrote: >> Hello, >> >> I've been chasing a particular UAF as reported by kasan >> (https://www.spinics.net/lists/kernel/msg2458136.html). However, one >> thing which I took notice of rather lately is

Re: kasan behavior when built with unsupported compiler

On 7.03.2017 19:51, Alexander Potapenko wrote: > On Tue, Mar 7, 2017 at 6:33 PM, Nikolay Borisov > wrote: >> >> >> On 7.03.2017 18:05, Alexander Potapenko wrote: >>> On Tue, Mar 7, 2017 at 4:54 PM, Dmitry Vyukov wrote: On Tue, Mar 7, 2017 at

Re: kasan behavior when built with unsupported compiler

On 7.03.2017 19:51, Alexander Potapenko wrote: > On Tue, Mar 7, 2017 at 6:33 PM, Nikolay Borisov > wrote: >> >> >> On 7.03.2017 18:05, Alexander Potapenko wrote: >>> On Tue, Mar 7, 2017 at 4:54 PM, Dmitry Vyukov wrote: On Tue, Mar 7, 2017 at 4:35 PM, Nikolay Borisov wrote: >

Re: kasan behavior when built with unsupported compiler

On Tue, Mar 7, 2017 at 6:33 PM, Nikolay Borisov wrote: > > > On 7.03.2017 18:05, Alexander Potapenko wrote: >> On Tue, Mar 7, 2017 at 4:54 PM, Dmitry Vyukov wrote: >>> On Tue, Mar 7, 2017 at 4:35 PM, Nikolay Borisov >>>

Re: kasan behavior when built with unsupported compiler

On Tue, Mar 7, 2017 at 6:33 PM, Nikolay Borisov wrote: > > > On 7.03.2017 18:05, Alexander Potapenko wrote: >> On Tue, Mar 7, 2017 at 4:54 PM, Dmitry Vyukov wrote: >>> On Tue, Mar 7, 2017 at 4:35 PM, Nikolay Borisov >>> wrote: Hello, I've been chasing a particular UAF as

Re: kasan behavior when built with unsupported compiler

On 7.03.2017 18:05, Alexander Potapenko wrote: > On Tue, Mar 7, 2017 at 4:54 PM, Dmitry Vyukov wrote: >> On Tue, Mar 7, 2017 at 4:35 PM, Nikolay Borisov >> wrote: >>> Hello, >>> >>> I've been chasing a particular UAF as reported by kasan >>>

Re: kasan behavior when built with unsupported compiler

On 7.03.2017 18:05, Alexander Potapenko wrote: > On Tue, Mar 7, 2017 at 4:54 PM, Dmitry Vyukov wrote: >> On Tue, Mar 7, 2017 at 4:35 PM, Nikolay Borisov >> wrote: >>> Hello, >>> >>> I've been chasing a particular UAF as reported by kasan >>>

Re: kasan behavior when built with unsupported compiler

On Tue, Mar 7, 2017 at 5:26 PM, Andrey Ryabinin wrote: > > > On 03/07/2017 06:54 PM, Dmitry Vyukov wrote: > >> >> Hi, >> >> Re the message that kasan is not supported while it's still enabled in the >> end. >> I think it's an issue related to gcc plugins. Originally

Re: kasan behavior when built with unsupported compiler

On Tue, Mar 7, 2017 at 5:26 PM, Andrey Ryabinin wrote: > > > On 03/07/2017 06:54 PM, Dmitry Vyukov wrote: > >> >> Hi, >> >> Re the message that kasan is not supported while it's still enabled in the >> end. >> I think it's an issue related to gcc plugins. Originally kasan was >> supported with

Re: kasan behavior when built with unsupported compiler

On 03/07/2017 06:35 PM, Nikolay Borisov wrote: > Hello, > > I've been chasing a particular UAF as reported by kasan > (https://www.spinics.net/lists/kernel/msg2458136.html). AFAICS it's not use after free, it's out-of-bounds access. > However, one > thing which I took notice of rather lately

Re: kasan behavior when built with unsupported compiler

On 03/07/2017 06:35 PM, Nikolay Borisov wrote: > Hello, > > I've been chasing a particular UAF as reported by kasan > (https://www.spinics.net/lists/kernel/msg2458136.html). AFAICS it's not use after free, it's out-of-bounds access. > However, one > thing which I took notice of rather lately

Re: kasan behavior when built with unsupported compiler

On Tue, Mar 7, 2017 at 4:54 PM, Dmitry Vyukov wrote: > On Tue, Mar 7, 2017 at 4:35 PM, Nikolay Borisov > wrote: >> Hello, >> >> I've been chasing a particular UAF as reported by kasan >> (https://www.spinics.net/lists/kernel/msg2458136.html).

Re: kasan behavior when built with unsupported compiler

On Tue, Mar 7, 2017 at 4:54 PM, Dmitry Vyukov wrote: > On Tue, Mar 7, 2017 at 4:35 PM, Nikolay Borisov > wrote: >> Hello, >> >> I've been chasing a particular UAF as reported by kasan >> (https://www.spinics.net/lists/kernel/msg2458136.html). However, one >> thing which I took notice of rather

Re: kasan behavior when built with unsupported compiler

On 03/07/2017 06:54 PM, Dmitry Vyukov wrote: > > Hi, > > Re the message that kasan is not supported while it's still enabled in the > end. > I think it's an issue related to gcc plugins. Originally kasan was > supported with 5.0+ thus the message. However, later we extended this > support to

Re: kasan behavior when built with unsupported compiler

On 03/07/2017 06:54 PM, Dmitry Vyukov wrote: > > Hi, > > Re the message that kasan is not supported while it's still enabled in the > end. > I think it's an issue related to gcc plugins. Originally kasan was > supported with 5.0+ thus the message. However, later we extended this > support to

Re: kasan behavior when built with unsupported compiler

On Tue, Mar 7, 2017 at 4:35 PM, Nikolay Borisov wrote: > Hello, > > I've been chasing a particular UAF as reported by kasan > (https://www.spinics.net/lists/kernel/msg2458136.html). However, one > thing which I took notice of rather lately is that I was building my >

Re: kasan behavior when built with unsupported compiler

On Tue, Mar 7, 2017 at 4:35 PM, Nikolay Borisov wrote: > Hello, > > I've been chasing a particular UAF as reported by kasan > (https://www.spinics.net/lists/kernel/msg2458136.html). However, one > thing which I took notice of rather lately is that I was building my > kernel with gcc 4.7.4 which