From c5ca0d11329ba710dd039720d5ff37401f9b2222 Mon Sep 17 00:00:00 2001 From: Konstantin Belousov Date: Thu, 13 Feb 2020 23:42:09 +0000 Subject: [PATCH] Handle non-plt IRELATIVE relocations, at least for x86. lld 10.0 seems to generate this relocation for rdtsc_mb() ifunc in our libc. Reported, reviewed, and tested by: dim (amd64, previous version) Discussed with: emaste Sponsored by: The FreeBSD Foundation MFC after: 1 week Differential revision: https://reviews.freebsd.org/D23652 --- libexec/rtld-elf/aarch64/reloc.c | 52 ++++++++++++++++------ libexec/rtld-elf/amd64/reloc.c | 69 ++++++++++++++++++++---------- libexec/rtld-elf/arm/reloc.c | 9 ++++ libexec/rtld-elf/i386/reloc.c | 61 ++++++++++++++++++-------- libexec/rtld-elf/mips/reloc.c | 9 ++++ libexec/rtld-elf/powerpc/reloc.c | 7 +++ libexec/rtld-elf/powerpc64/reloc.c | 7 +++ libexec/rtld-elf/riscv/reloc.c | 9 ++++ libexec/rtld-elf/rtld.c | 5 ++- libexec/rtld-elf/rtld.h | 2 + libexec/rtld-elf/sparc64/reloc.c | 9 ++++ 11 files changed, 185 insertions(+), 54 deletions(-) diff --git a/libexec/rtld-elf/aarch64/reloc.c b/libexec/rtld-elf/aarch64/reloc.c index f1c66816fcee..073c0dfaf1a2 100644 --- a/libexec/rtld-elf/aarch64/reloc.c +++ b/libexec/rtld-elf/aarch64/reloc.c @@ -258,27 +258,52 @@ reloc_jmpslots(Obj_Entry *obj, int flags, RtldLockState *lockstate) return (0); } +static void +reloc_iresolve_one(Obj_Entry *obj, const Elf_Rela *rela, + RtldLockState *lockstate) +{ + Elf_Addr *where, target, *ptr; + + ptr = (Elf_Addr *)(obj->relocbase + rela->r_addend); + where = (Elf_Addr *)(obj->relocbase + rela->r_offset); + lock_release(rtld_bind_lock, lockstate); + target = call_ifunc_resolver(ptr); + wlock_acquire(rtld_bind_lock, lockstate); + *where = target; +} + int reloc_iresolve(Obj_Entry *obj, struct Struct_RtldLockState *lockstate) { const Elf_Rela *relalim; const Elf_Rela *rela; - Elf_Addr *where, target, *ptr; if (!obj->irelative) return (0); - relalim = (const Elf_Rela *)((const char *)obj->pltrela + obj->pltrelasize); - for (rela = obj->pltrela; rela < relalim; rela++) { - if (ELF_R_TYPE(rela->r_info) == R_AARCH64_IRELATIVE) { - ptr = (Elf_Addr *)(obj->relocbase + rela->r_addend); - where = (Elf_Addr *)(obj->relocbase + rela->r_offset); - lock_release(rtld_bind_lock, lockstate); - target = call_ifunc_resolver(ptr); - wlock_acquire(rtld_bind_lock, lockstate); - *where = target; - } - } obj->irelative = false; + relalim = (const Elf_Rela *)((const char *)obj->pltrela + + obj->pltrelasize); + for (rela = obj->pltrela; rela < relalim; rela++) { + if (ELF_R_TYPE(rela->r_info) == R_AARCH64_IRELATIVE) + reloc_iresolve_one(obj, rela, lockstate); + } + return (0); +} + +int +reloc_iresolve_nonplt(Obj_Entry *obj, struct Struct_RtldLockState *lockstate) +{ + const Elf_Rela *relalim; + const Elf_Rela *rela; + + if (!obj->irelative_nonplt) + return (0); + obj->irelative_nonplt = false; + relalim = (const Elf_Rela *)((const char *)obj->rela + obj->relasize); + for (rela = obj->rela; rela < relalim; rela++) { + if (ELF_R_TYPE(rela->r_info) == R_AARCH64_IRELATIVE) + reloc_iresolve_one(obj, rela, lockstate); + } return (0); } @@ -498,6 +523,9 @@ reloc_non_plt(Obj_Entry *obj, Obj_Entry *obj_rtld, int flags, break; case R_AARCH64_NONE: break; + case R_AARCH64_IRELATIVE: + obj->irelative_nonplt = true; + break; default: rtld_printf("%s: Unhandled relocation %lu\n", obj->path, ELF_R_TYPE(rela->r_info)); diff --git a/libexec/rtld-elf/amd64/reloc.c b/libexec/rtld-elf/amd64/reloc.c index c88f98a1835b..ae15f6a41dec 100644 --- a/libexec/rtld-elf/amd64/reloc.c +++ b/libexec/rtld-elf/amd64/reloc.c @@ -303,6 +303,10 @@ reloc_non_plt(Obj_Entry *obj, Obj_Entry *obj_rtld, int flags, case R_X86_64_RELATIVE: *where = (Elf_Addr)(obj->relocbase + rela->r_addend); break; + case R_X86_64_IRELATIVE: + obj->irelative_nonplt = true; + break; + /* * missing: * R_X86_64_GOTPCREL, R_X86_64_32, R_X86_64_32S, R_X86_64_16, @@ -410,34 +414,53 @@ reloc_jmpslot(Elf_Addr *where, Elf_Addr target, return (target); } +static void +reloc_iresolve_one(Obj_Entry *obj, const Elf_Rela *rela, + RtldLockState *lockstate) +{ + Elf_Addr *where, target, *ptr; + + ptr = (Elf_Addr *)(obj->relocbase + rela->r_addend); + where = (Elf_Addr *)(obj->relocbase + rela->r_offset); + lock_release(rtld_bind_lock, lockstate); + target = call_ifunc_resolver(ptr); + wlock_acquire(rtld_bind_lock, lockstate); + *where = target; +} + int reloc_iresolve(Obj_Entry *obj, RtldLockState *lockstate) { - const Elf_Rela *relalim; - const Elf_Rela *rela; + const Elf_Rela *relalim; + const Elf_Rela *rela; - if (!obj->irelative) - return (0); - relalim = (const Elf_Rela *)((const char *)obj->pltrela + obj->pltrelasize); - for (rela = obj->pltrela; rela < relalim; rela++) { - Elf_Addr *where, target, *ptr; - - switch (ELF_R_TYPE(rela->r_info)) { - case R_X86_64_JMP_SLOT: - break; - - case R_X86_64_IRELATIVE: - ptr = (Elf_Addr *)(obj->relocbase + rela->r_addend); - where = (Elf_Addr *)(obj->relocbase + rela->r_offset); - lock_release(rtld_bind_lock, lockstate); - target = call_ifunc_resolver(ptr); - wlock_acquire(rtld_bind_lock, lockstate); - *where = target; - break; + if (!obj->irelative) + return (0); + obj->irelative = false; + relalim = (const Elf_Rela *)((const char *)obj->pltrela + + obj->pltrelasize); + for (rela = obj->pltrela; rela < relalim; rela++) { + if (ELF_R_TYPE(rela->r_info) == R_X86_64_IRELATIVE) + reloc_iresolve_one(obj, rela, lockstate); } - } - obj->irelative = false; - return (0); + return (0); +} + +int +reloc_iresolve_nonplt(Obj_Entry *obj, RtldLockState *lockstate) +{ + const Elf_Rela *relalim; + const Elf_Rela *rela; + + if (!obj->irelative_nonplt) + return (0); + obj->irelative_nonplt = false; + relalim = (const Elf_Rela *)((const char *)obj->rela + obj->relasize); + for (rela = obj->rela; rela < relalim; rela++) { + if (ELF_R_TYPE(rela->r_info) == R_X86_64_IRELATIVE) + reloc_iresolve_one(obj, rela, lockstate); + } + return (0); } int diff --git a/libexec/rtld-elf/arm/reloc.c b/libexec/rtld-elf/arm/reloc.c index 09213413f66d..d389bb0f8e87 100644 --- a/libexec/rtld-elf/arm/reloc.c +++ b/libexec/rtld-elf/arm/reloc.c @@ -451,6 +451,15 @@ reloc_iresolve(Obj_Entry *obj __unused, return (0); } +int +reloc_iresolve_nonplt(Obj_Entry *obj __unused, + struct Struct_RtldLockState *lockstate __unused) +{ + + /* XXX not implemented */ + return (0); +} + int reloc_gnu_ifunc(Obj_Entry *obj __unused, int flags __unused, struct Struct_RtldLockState *lockstate __unused) diff --git a/libexec/rtld-elf/i386/reloc.c b/libexec/rtld-elf/i386/reloc.c index ef6e805aeeb4..7f2dd0c69ef1 100644 --- a/libexec/rtld-elf/i386/reloc.c +++ b/libexec/rtld-elf/i386/reloc.c @@ -263,6 +263,9 @@ reloc_non_plt(Obj_Entry *obj, Obj_Entry *obj_rtld, int flags, case R_386_TLS_DTPOFF32: *where += (Elf_Addr) def->st_value; break; + case R_386_IRELATIVE: + obj->irelative_nonplt = true; + break; default: _rtld_error("%s: Unsupported relocation type %d" " in non-PLT relocations\n", obj->path, @@ -365,29 +368,51 @@ reloc_jmpslot(Elf_Addr *where, Elf_Addr target, return (target); } +static void +reloc_iresolve_one(Obj_Entry *obj, const Elf_Rel *rel, + RtldLockState *lockstate) +{ + Elf_Addr *where, target; + + where = (Elf_Addr *)(obj->relocbase + rel->r_offset); + lock_release(rtld_bind_lock, lockstate); + target = call_ifunc_resolver(obj->relocbase + *where); + wlock_acquire(rtld_bind_lock, lockstate); + *where = target; +} + int reloc_iresolve(Obj_Entry *obj, RtldLockState *lockstate) { - const Elf_Rel *rellim; - const Elf_Rel *rel; - Elf_Addr *where, target; + const Elf_Rel *rellim; + const Elf_Rel *rel; - if (!obj->irelative) - return (0); - rellim = (const Elf_Rel *)((const char *)obj->pltrel + obj->pltrelsize); - for (rel = obj->pltrel; rel < rellim; rel++) { - switch (ELF_R_TYPE(rel->r_info)) { - case R_386_IRELATIVE: - where = (Elf_Addr *)(obj->relocbase + rel->r_offset); - lock_release(rtld_bind_lock, lockstate); - target = call_ifunc_resolver(obj->relocbase + *where); - wlock_acquire(rtld_bind_lock, lockstate); - *where = target; - break; + if (!obj->irelative) + return (0); + obj->irelative = false; + rellim = (const Elf_Rel *)((const char *)obj->pltrel + obj->pltrelsize); + for (rel = obj->pltrel; rel < rellim; rel++) { + if (ELF_R_TYPE(rel->r_info) == R_386_RELATIVE) + reloc_iresolve_one(obj, rel, lockstate); } - } - obj->irelative = false; - return (0); + return (0); +} + +int +reloc_iresolve_nonplt(Obj_Entry *obj, RtldLockState *lockstate) +{ + const Elf_Rel *rellim; + const Elf_Rel *rel; + + if (!obj->irelative_nonplt) + return (0); + obj->irelative_nonplt = false; + rellim = (const Elf_Rel *)((const char *)obj->rel + obj->relsize); + for (rel = obj->rel; rel < rellim; rel++) { + if (ELF_R_TYPE(rel->r_info) == R_386_IRELATIVE) + reloc_iresolve_one(obj, rel, lockstate); + } + return (0); } int diff --git a/libexec/rtld-elf/mips/reloc.c b/libexec/rtld-elf/mips/reloc.c index 8bc3e95cb4d3..b116978114b1 100644 --- a/libexec/rtld-elf/mips/reloc.c +++ b/libexec/rtld-elf/mips/reloc.c @@ -722,6 +722,15 @@ reloc_iresolve(Obj_Entry *obj __unused, return (0); } +int +reloc_iresolve_nonplt(Obj_Entry *obj __unused, + struct Struct_RtldLockState *lockstate __unused) +{ + + /* XXX not implemented */ + return (0); +} + int reloc_gnu_ifunc(Obj_Entry *obj __unused, int flags __unused, struct Struct_RtldLockState *lockstate __unused) diff --git a/libexec/rtld-elf/powerpc/reloc.c b/libexec/rtld-elf/powerpc/reloc.c index f5fcc6756751..e98252833014 100644 --- a/libexec/rtld-elf/powerpc/reloc.c +++ b/libexec/rtld-elf/powerpc/reloc.c @@ -652,6 +652,13 @@ reloc_iresolve(Obj_Entry *obj, return (0); } +int +reloc_iresolve_nonplt(Obj_Entry *obj __unused, + struct Struct_RtldLockState *lockstate __unused) +{ + return (0); +} + int reloc_gnu_ifunc(Obj_Entry *obj __unused, int flags __unused, struct Struct_RtldLockState *lockstate __unused) diff --git a/libexec/rtld-elf/powerpc64/reloc.c b/libexec/rtld-elf/powerpc64/reloc.c index 4a14836752c0..e2fbb109f632 100644 --- a/libexec/rtld-elf/powerpc64/reloc.c +++ b/libexec/rtld-elf/powerpc64/reloc.c @@ -652,6 +652,13 @@ reloc_gnu_ifunc(Obj_Entry *obj __unused, int flags __unused, #endif } +int +reloc_iresolve_nonplt(Obj_Entry *obj __unused, + struct Struct_RtldLockState *lockstate __unused) +{ + return (0); +} + void init_pltgot(Obj_Entry *obj) { diff --git a/libexec/rtld-elf/riscv/reloc.c b/libexec/rtld-elf/riscv/reloc.c index c421270167f5..79a045ff0253 100644 --- a/libexec/rtld-elf/riscv/reloc.c +++ b/libexec/rtld-elf/riscv/reloc.c @@ -211,6 +211,15 @@ reloc_iresolve(Obj_Entry *obj __unused, return (0); } +int +reloc_iresolve_nonplt(Obj_Entry *obj __unused, + struct Struct_RtldLockState *lockstate __unused) +{ + + /* XXX not implemented */ + return (0); +} + int reloc_gnu_ifunc(Obj_Entry *obj __unused, int flags __unused, struct Struct_RtldLockState *lockstate __unused) diff --git a/libexec/rtld-elf/rtld.c b/libexec/rtld-elf/rtld.c index ba08785762f5..b2c2f1f28765 100644 --- a/libexec/rtld-elf/rtld.c +++ b/libexec/rtld-elf/rtld.c @@ -3034,10 +3034,13 @@ resolve_object_ifunc(Obj_Entry *obj, bool bind_now, int flags, if (obj->ifuncs_resolved) return (0); obj->ifuncs_resolved = true; - if (!obj->irelative && !((obj->bind_now || bind_now) && obj->gnu_ifunc)) + if (!obj->irelative && !obj->irelative_nonplt && + !((obj->bind_now || bind_now) && obj->gnu_ifunc)) return (0); if (obj_disable_relro(obj) == -1 || (obj->irelative && reloc_iresolve(obj, lockstate) == -1) || + (obj->irelative_nonplt && reloc_iresolve_nonplt(obj, + lockstate) == -1) || ((obj->bind_now || bind_now) && obj->gnu_ifunc && reloc_gnu_ifunc(obj, flags, lockstate) == -1) || obj_enforce_relro(obj) == -1) diff --git a/libexec/rtld-elf/rtld.h b/libexec/rtld-elf/rtld.h index f21b1d79cf20..85755667fda8 100644 --- a/libexec/rtld-elf/rtld.h +++ b/libexec/rtld-elf/rtld.h @@ -264,6 +264,7 @@ typedef struct Struct_Obj_Entry { bool dag_inited : 1; /* Object has its DAG initialized. */ bool filtees_loaded : 1; /* Filtees loaded */ bool irelative : 1; /* Object has R_MACHDEP_IRELATIVE relocs */ + bool irelative_nonplt : 1; /* Object has R_MACHDEP_IRELATIVE non-plt relocs */ bool gnu_ifunc : 1; /* Object has references to STT_GNU_IFUNC */ bool non_plt_gnu_ifunc : 1; /* Object has non-plt IFUNC references */ bool ifuncs_resolved : 1; /* Object ifuncs were already resolved */ @@ -406,6 +407,7 @@ int reloc_non_plt(Obj_Entry *, Obj_Entry *, int flags, int reloc_plt(Obj_Entry *, int flags, struct Struct_RtldLockState *); int reloc_jmpslots(Obj_Entry *, int flags, struct Struct_RtldLockState *); int reloc_iresolve(Obj_Entry *, struct Struct_RtldLockState *); +int reloc_iresolve_nonplt(Obj_Entry *, struct Struct_RtldLockState *); int reloc_gnu_ifunc(Obj_Entry *, int flags, struct Struct_RtldLockState *); void ifunc_init(Elf_Auxinfo[__min_size(AT_COUNT)]); void pre_init(void); diff --git a/libexec/rtld-elf/sparc64/reloc.c b/libexec/rtld-elf/sparc64/reloc.c index 4b0eb7d75b19..3434ed09d82f 100644 --- a/libexec/rtld-elf/sparc64/reloc.c +++ b/libexec/rtld-elf/sparc64/reloc.c @@ -569,6 +569,15 @@ reloc_iresolve(Obj_Entry *obj __unused, return (0); } +int +reloc_iresolve_nonplt(Obj_Entry *obj __unused, + struct Struct_RtldLockState *lockstate __unused) +{ + + /* XXX not implemented */ + return (0); +} + int reloc_gnu_ifunc(Obj_Entry *obj __unused, int flags __unused, struct Struct_RtldLockState *lockstate __unused)