search for: sto_tagged

Displaying 4 results from an estimated 4 matches for "sto_tagged".

2020 Sep 17
4
[MTE] Globals Tagging - Discussion
...tize=memtag. Protection of read-only globals would be enabled-by-default, but can be disabled at compile time behind a flag (likely -f(no)sanitize-memtag-ro-globals). a) Dynamic symbols (int f; extern int f;) 1. Mark all tagged global data symbols in the dynamic symbol table as st_other.STO_TAGGED. 2. Teach the loader to read the symbol table at load time (and dlopen()) prior to relocations, and apply random memory tags (via. `irg -> stg`) to each STO_TAGGED carrying global. b) Hidden Symbols (static int g; or -fvisibility=hidden) 1. Have the compiler mark hidden tag...
2020 Sep 18
2
[MTE] Globals Tagging - Discussion
...be enabled-by-default, but can be > disabled at compile time behind a flag (likely > -f(no)sanitize-memtag-ro-globals). > > > > > > a) Dynamic symbols (int f; extern int f;) > > > > Mark all tagged global data symbols in the dynamic symbol table as > st_other.STO_TAGGED. > > > > Teach the loader to read the symbol table at load time (and dlopen()) > prior to relocations, and apply random memory tags (via. `irg -> stg`) to > each STO_TAGGED carrying global. > > > > b) Hidden Symbols (static int g; or -fvisibility=hidden) > > &...
2020 Sep 21
2
[MTE] Globals Tagging - Discussion
...ever happen. > > The symbols are resized in order to prevent smaller untagged symbols from getting into the padding of the 16-byte aligned tagged ones. > I'm not sure if it's desirable to change the symbol size just for this reason. The linker could always suppress such packing for STO_TAGGED symbols. > > In any case, since all sizes and alignments are known, the compiler should be allowed to emit RELATIVE in the rounded-up array case. > >> >> >> On Fri, Sep 18, 2020 at 4:10 AM David Spickett <david.spickett at linaro.org> wrote: >>> >>&gt...
2020 Oct 09
3
[MTE] Globals Tagging - Discussion
...lement independently, not an > llvm vs compiler-rt internal design or android only design.) > > > > > a) Dynamic symbols (int f; extern int f;) > > > > 1. > > > > Mark all tagged global data symbols in the dynamic symbol table as > > st_other.STO_TAGGED. > > note: these bits are not really reserved for os or processor > specific use in ELF. in practice they are processor specific > so it will be STO_AARCH64_TAGGED. > > note2: undefined symbol references will need correct marking > too if objects may get copy relocated into the...