WIP add support for GNU LibC TLS model

Unlike on Windows, TLS index isn't part of the module format. glibc stores
it in the opaque link_map struct. There are many different heuristics
a debugger can use to locate it but most of them are unreliable and
prone to errors, or don't work when debugger attaches to a process.
We adopt the newer approach of looking for special symbols
in glibc that provide TLS index offset. These symbols were added in
2021, so programs linked with older glibc won't have TLS support.
This commit is contained in:
Nikita Smith
2025-11-21 16:41:35 -08:00
parent 7347d2f1bc
commit 0565fdef0a
8 changed files with 361 additions and 238 deletions
+19 -3
View File
@@ -59,6 +59,17 @@ struct CTRL_UserBreakpointList
U64 count;
};
////////////////////////////////
//~ Dynamic Linker Types
typedef U32 CTRL_TlsModel;
enum
{
CTRL_TlsModel_Null,
CTRL_TlsModel_WinodwsNt,
CTRL_TlsModel_Gnu
};
////////////////////////////////
//~ rjf: Entity Handle Types
@@ -119,6 +130,9 @@ struct CTRL_Entity
U64 timestamp;
CTRL_UserBreakpointFlags bp_flags;
String8 string;
CTRL_TlsModel tls_model;
U64 tls_index;
U64 tls_offset;
};
typedef struct CTRL_EntityNode CTRL_EntityNode;
@@ -512,11 +526,14 @@ struct CTRL_Event
U64 rip_vaddr;
U64 stack_base;
U64 tls_root;
U64 tls_index;
U64 tls_offset;
U64 timestamp;
U32 exception_code;
U32 rgba;
CTRL_UserBreakpointFlags bp_flags;
String8 string;
CTRL_TlsModel tls_model;
};
typedef struct CTRL_EventNode CTRL_EventNode;
@@ -603,7 +620,6 @@ struct CTRL_ModuleImageInfoCacheNode
EH_FrameHdr eh_frame_hdr;
EH_PtrCtx eh_ptr_ctx;
U64 entry_point_voff;
Rng1U64 tls_vaddr_range;
String8 initial_debug_info_path;
Rng1U64 raddbg_section_voff_range;
String8 raddbg_data;
@@ -776,6 +792,7 @@ internal U64 ctrl_hash_from_string(String8 string);
internal U64 ctrl_hash_from_handle(CTRL_Handle handle);
internal CTRL_EventCause ctrl_event_cause_from_dmn_event_kind(DMN_EventKind event_kind);
internal CTRL_ExceptionKind ctrl_exception_kind_from_dmn(DMN_ExceptionKind kind);
internal CTRL_TlsModel ctrl_dynamic_linker_type_from_dmn(DMN_TlsModel type);
internal String8 ctrl_string_from_event_kind(CTRL_EventKind kind);
internal String8 ctrl_string_from_msg_kind(CTRL_MsgKind kind);
internal CTRL_EntityKind ctrl_entity_kind_from_string(String8 string);
@@ -916,7 +933,6 @@ internal B32 ctrl_thread_write_reg_block(CTRL_Handle thread, void *block);
//- rjf: cache lookups
internal PE_IntelPdata *ctrl_intel_pdata_from_module_voff(Arena *arena, CTRL_Handle module_handle, U64 voff);
internal U64 ctrl_entry_point_voff_from_module(CTRL_Handle module_handle);
internal Rng1U64 ctrl_tls_vaddr_range_from_module(CTRL_Handle module_handle);
internal String8 ctrl_initial_debug_info_path_from_module(Arena *arena, CTRL_Handle module_handle);
internal String8 ctrl_raddbg_data_from_module(Arena *arena, CTRL_Handle module_handle);
@@ -993,7 +1009,7 @@ internal void ctrl_thread__module_close(CTRL_Handle process, CTRL_Handle module,
//- rjf: attached process running/event gathering
internal DMN_Event *ctrl_thread__next_dmn_event(Arena *arena, DMN_CtrlCtx *ctrl_ctx, CTRL_Msg *msg, DMN_RunCtrls *run_ctrls, CTRL_Spoof *spoof);
//- rjf: eval helpers
//- rjf: eval helpers
internal U64 ctrl_eval_space_gen(E_Space space);
internal B32 ctrl_eval_space_read(E_Space space, void *out, Rng1U64 vaddr_range);