search for: redzon

...fa fa fa fa 0x0c047fff9e30: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa 0x0c047fff9e40: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa Shadow byte legend (one shadow byte represents 8 application bytes): Addressable: 00 Partially addressable: 01 02 03 04 05 06 07 Heap left redzone: fa Heap right redzone: fb Freed heap region: fd Stack left redzone: f1 Stack mid redzone: f2 Stack right redzone: f3 Stack partial redzone: f4 Stack after return: f5 Stack use after scope: f8 Global redzone: f9 Global init orde...

...f9 f9 0x000080160cc0: f9 f9 f9 f9 00 00 00 00 00 f9 f9 f9 f9 f9 f9 f9 0x000080160cd0: 00 00 00 00 05 f9 f9 f9 f9 f9 f9 f9 00 00 00 00 Shadow byte legend (one shadow byte represents 8 application bytes): Addressable: 00 Partially addressable: 01 02 03 04 05 06 07 Heap left redzone: fa Freed heap region: fd Stack left redzone: f1 Stack mid redzone: f2 Stack right redzone: f3 Stack after return: f5 Stack use after scope: f8 Global redzone: f9 Global init order: f6 Poisoned by user: f7 Contai...

...0x000080160cd0: 00 00 00 00 05 f9 f9 f9 f9 f9 f9 f9 00 00 00 00 > > > > Shadow byte legend (one shadow byte represents 8 application bytes): > > > > Addressable: 00 > > > > Partially addressable: 01 02 03 04 05 06 07 > > > > Heap left redzone: fa > > > > Freed heap region: fd > > > > Stack left redzone: f1 > > > > Stack mid redzone: f2 > > > > Stack right redzone: f3 > > > > Stack after return: f5 > > > > Stack use after...

...t;> > > >> > Shadow byte legend (one shadow byte represents 8 application bytes): > >> > > >> > Addressable: 00 > >> > > >> > Partially addressable: 01 02 03 04 05 06 07 > >> > > >> > Heap left redzone: fa > >> > > >> > Freed heap region: fd > >> > > >> > Stack left redzone: f1 > >> > > >> > Stack mid redzone: f2 > >> > > >> > Stack right redzone: f3 > >> &g...

...fa fa fd fa 0x0c047fff9d40: fa fa 00 01 fa fa fd fa fa fa fd fa fa fa 00 01 0x0c047fff9d50: fa fa fd fa fa fa fd fa fa fa 02 fa fa fa fd fa Shadow byte legend (one shadow byte represents 8 application bytes): Addressable: 00 Partially addressable: 01 02 03 04 05 06 07 Heap left redzone: fa Heap right redzone: fb Freed heap region: fd Stack left redzone: f1 Stack mid redzone: f2 Stack right redzone: f3 Stack partial redzone: f4 Stack after return: f5 Stack use after scope: f8 Global redzone: f9 Global init orde...

...f2 f2 f2 f2 0x1000618959c0: f2 f2 00 f2 f2 f2 f3 f3 f3 f3 00 00 00 00 00 00 0x1000618959d0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 Shadow byte legend (one shadow byte represents 8 application bytes): Addressable: 00 Partially addressable: 01 02 03 04 05 06 07 Heap left redzone: fa Freed heap region: fd Stack left redzone: f1 Stack mid redzone: f2 Stack right redzone: f3 Stack after return: f5 Stack use after scope: f8 Global redzone: f9 Global init order: f6 Poisoned by user: f7 Container overfl...

Author: arutz Repository: /hg/zfs-crypto/gate Revision: d6168689a27a22f7ca097c0dfd29141db33d147f Log message: 5097578 cdrw dumps a core due to redzone violation Files: update: usr/src/cmd/cdrw/device.c update: usr/src/cmd/cdrw/write_audio.c

...fa fa 00 00 0x0c047fff9da0: fa fa 00 00 fa fa 05 fa fa fa 05 fa fa fa 07 fa 0x0c047fff9db0: fa fa fd fd fa fa 00 04 fa fa fd fd fa fa fd fd Shadow byte legend (one shadow byte represents 8 application bytes): Addressable: 00 Partially addressable: 01 02 03 04 05 06 07 Heap left redzone: fa Heap right redzone: fb Freed heap region: fd Stack left redzone: f1 Stack mid redzone: f2 Stack right redzone: f3 Stack partial redzone: f4 Stack after return: f5 Stack use after scope: f8 Global redzone: f9 Global init orde...

...p being put into the .cstring > section, for which the following rules apply: > - the strings can't contain zeroes in their bodies > - the link editor places only one copy of each literal into the > output file's section > > ASan usually instruments the globals by adding redzones to the end of > them and creating a structure that contains the size of a global with > and without the redzone. > For the aforementioned strings the linker will delete the redzones, > but leave that structure untouched, which will lead to corrupt shadow > memory at run time. >...

...fa fa fd fa 0x0c047fff9d40: fa fa 00 01 fa fa fd fa fa fa fd fa fa fa 00 01 0x0c047fff9d50: fa fa fd fa fa fa fd fa fa fa 02 fa fa fa fd fa Shadow byte legend (one shadow byte represents 8 application bytes): Addressable: 00 Partially addressable: 01 02 03 04 05 06 07 Heap left redzone: fa Heap right redzone: fb Freed heap region: fd Stack left redzone: f1 Stack mid redzone: f2 Stack right redzone: f3 Stack partial redzone: f4 Stack after return: f5 Stack use after scope: f8 Global redzone: f9 Global init orde...

...fa fa fa fa fa fa fa 0x2ef20230: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa 0x2ef20240: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa Shadow byte legend (one shadow byte represents 8 application bytes): Addressable: 00 Partially addressable: 01 02 03 04 05 06 07 Heap left redzone: fa Heap righ redzone: fb Freed Heap region: fd Stack left redzone: f1 Stack mid redzone: f2 Stack right redzone: f3 Stack partial redzone: f4 Stack after return: f5 Stack use after scope: f8 Global redzone: f9 Global init order: f6 Poisoned...

I'm struggling to explain an ASAN report I'm now getting that I didn't get previously on the same code. In fact the report only happens with -O2 and not when I remove the -O flags which makes it hard to debug and makes me suspect it's dependent on exactly which instructions the code generation decides to access the bytes involved. Afaict the C code shouldn't be accessing the

...fa fa fa fa 0x0c0e80013990: fd fd fd fd fd fd fd fd fd fa fa fa fa fa fd fd 0x0c0e800139a0: fd fd fd fd fd fd fd fa fa fa fa fa fd fd fd fd Shadow byte legend (one shadow byte represents 8 application bytes): Addressable: 00 Partially addressable: 01 02 03 04 05 06 07 Heap left redzone: fa Heap right redzone: fb Freed heap region: fd Stack left redzone: f1 Stack mid redzone: f2 Stack right redzone: f3 Stack partial redzone: f4 Stack after return: f5 Stack use after scope: f8 Global redzone: f9 Global init orde...

Hi, In order to find out-of-bound accesses to global objects with AddressSanitizer ( http://code.google.com/p/address-sanitizer/wiki/AddressSanitizer) I need to create redzones to the left and to the right of every global variable. I tried the following: Before: @Extern = global [10 x i8] zeroinitializer, align 1 After: %0 = type { [32 x i8], [10 x i8], [54 x i8] } @Extern_asan_redzone = global %0 zeroinitializer, align 1 @0 = global [10 x i8] zeroinitializer,...

I've finished my initial set of patches to make 32-byte shadow granularity work on x86. Here is a summary of the changes from last week: - As discussed, I added a full redzone after every stack variable. - We discussed adding a -fsanitize-address-granularity=N flag, but I found the following existing flag has been sufficient for my purposes: -asan-mapping-scale N. If anyone thinks I should add the flag anyways, possibly replacing the latter, please let me know....

...string >> section, for which the following rules apply: >> - the strings can't contain zeroes in their bodies >> - the link editor places only one copy of each literal into the >> output file's section >> >> ASan usually instruments the globals by adding redzones to the end of >> them and creating a structure that contains the size of a global with >> and without the redzone. >> For the aforementioned strings the linker will delete the redzones, >> but leave that structure untouched, which will lead to corrupt shadow >> memor...

...omplicated than asan/tsan and run-time part is very simple). FAQ: Q. Why can't we combine msan and asan? A: Valgrind/Memcheck and DrMemory do exactly that -- and pay large performance and memory costs. Addressability checker (like asan) requires little shadow memory, but needs large redzone around allocated objects. Tools that track uninitialized/tainted data need bit-per-bit shadow in worst case, but don't need redzones. So, if we merge the tools together we multiply the memory overheads. The instrumentation costs in a combined tool are mostly added to each oth...

...talk, bullshit walks. It would be interesting to be proven wrong. Here's an article with numbers: http://shipilev.net/blog/2014/on-the-fence-with-dependencies/ I think they're suggesting using a negative offset, which is safe as long as it doesn't page fault, even though we have the redzone disabled. --Andy

...talk, bullshit walks. It would be interesting to be proven wrong. Here's an article with numbers: http://shipilev.net/blog/2014/on-the-fence-with-dependencies/ I think they're suggesting using a negative offset, which is safe as long as it doesn't page fault, even though we have the redzone disabled. --Andy

...to get a specific number of bytes to allocate. You would compile bar, note down how many bytes of stack it would have required, then add that as an attribute. The IR level could only make a good guess as to how many bytes we need. Saying that, this is basically like having a compiler controlled redzone. Thats what made me think of it in the first place. If bar needed only 4 bytes, and the system supports a redzone, then its likely bar wouldn’t have allocated anything on the stack. I just extended that so that the number of bytes is able to be larger that the number rezone’s typically provide....