From 1bd888d0b705fa5ab7b443724288f7ba12939533 Mon Sep 17 00:00:00 2001 From: "H.J. Lu" Date: Fri, 18 Jun 2021 11:53:55 -0700 Subject: [PATCH] Initial support for GNU_PROPERTY_1_NEEDED 1. Add GNU_PROPERTY_1_NEEDED: #define GNU_PROPERTY_1_NEEDED GNU_PROPERTY_UINT32_OR_LO to indicate the needed properties by the object file. 2. Add GNU_PROPERTY_1_NEEDED_INDIRECT_EXTERN_ACCESS: #define GNU_PROPERTY_1_NEEDED_INDIRECT_EXTERN_ACCESS (1U << 0) to indicate that the object file requires canonical function pointers and cannot be used with copy relocation. 3. Scan GNU_PROPERTY_1_NEEDED property and store it in l_1_needed. Reviewed-by: Adhemerval Zanella --- elf/elf.h | 17 +++++++++++++++++ sysdeps/generic/dl-prop.h | 9 ++++++++- sysdeps/generic/link_map.h | 3 ++- sysdeps/x86/dl-prop.h | 19 ++++++++++++++----- sysdeps/x86/link_map.h | 2 ++ 5 files changed, 43 insertions(+), 7 deletions(-) diff --git a/elf/elf.h b/elf/elf.h index 4738dfa28f..50f87baceb 100644 --- a/elf/elf.h +++ b/elf/elf.h @@ -1312,6 +1312,23 @@ typedef struct /* No copy relocation on protected data symbol. */ #define GNU_PROPERTY_NO_COPY_ON_PROTECTED 2 +/* A 4-byte unsigned integer property: A bit is set if it is set in all + relocatable inputs. */ +#define GNU_PROPERTY_UINT32_AND_LO 0xb0000000 +#define GNU_PROPERTY_UINT32_AND_HI 0xb0007fff + +/* A 4-byte unsigned integer property: A bit is set if it is set in any + relocatable inputs. */ +#define GNU_PROPERTY_UINT32_OR_LO 0xb0008000 +#define GNU_PROPERTY_UINT32_OR_HI 0xb000ffff + +/* The needed properties by the object file. */ +#define GNU_PROPERTY_1_NEEDED GNU_PROPERTY_UINT32_OR_LO + +/* Set if the object file requires canonical function pointers and + cannot be used with copy relocation. */ +#define GNU_PROPERTY_1_NEEDED_INDIRECT_EXTERN_ACCESS (1U << 0) + /* Processor-specific semantics, lo */ #define GNU_PROPERTY_LOPROC 0xc0000000 /* Processor-specific semantics, hi */ diff --git a/sysdeps/generic/dl-prop.h b/sysdeps/generic/dl-prop.h index eaee8052b6..207aadb35d 100644 --- a/sysdeps/generic/dl-prop.h +++ b/sysdeps/generic/dl-prop.h @@ -47,7 +47,14 @@ static inline int __attribute__ ((always_inline)) _dl_process_gnu_property (struct link_map *l, int fd, uint32_t type, uint32_t datasz, void *data) { - return 0; + /* Continue until GNU_PROPERTY_1_NEEDED is found. */ + if (type == GNU_PROPERTY_1_NEEDED) + { + if (datasz == 4) + l->l_1_needed = *(unsigned int *) data; + return 0; + } + return 1; } #endif /* _DL_PROP_H */ diff --git a/sysdeps/generic/link_map.h b/sysdeps/generic/link_map.h index a056184690..9f482b8c20 100644 --- a/sysdeps/generic/link_map.h +++ b/sysdeps/generic/link_map.h @@ -1 +1,2 @@ -/* No architecture specific definitions. */ +/* GNU_PROPERTY_1_NEEDED of this object. */ +unsigned int l_1_needed; diff --git a/sysdeps/x86/dl-prop.h b/sysdeps/x86/dl-prop.h index 56bd020b3c..385548fad3 100644 --- a/sysdeps/x86/dl-prop.h +++ b/sysdeps/x86/dl-prop.h @@ -97,6 +97,7 @@ _dl_process_property_note (struct link_map *l, const ElfW(Nhdr) *note, const ElfW(Addr) start = (ElfW(Addr)) note; + unsigned int needed_1 = 0; unsigned int feature_1_and = 0; unsigned int isa_1_needed = 0; unsigned int last_type = 0; @@ -141,7 +142,8 @@ _dl_process_property_note (struct link_map *l, const ElfW(Nhdr) *note, last_type = type; if (type == GNU_PROPERTY_X86_FEATURE_1_AND - || type == GNU_PROPERTY_X86_ISA_1_NEEDED) + || type == GNU_PROPERTY_X86_ISA_1_NEEDED + || type == GNU_PROPERTY_1_NEEDED) { /* The sizes of types which we are searching for are 4 bytes. There is no point to continue if this @@ -151,12 +153,18 @@ _dl_process_property_note (struct link_map *l, const ElfW(Nhdr) *note, /* NB: Stop the scan only after seeing all types which we are searching for. */ - _Static_assert ((GNU_PROPERTY_X86_ISA_1_NEEDED > - GNU_PROPERTY_X86_FEATURE_1_AND), + _Static_assert (((GNU_PROPERTY_X86_ISA_1_NEEDED + > GNU_PROPERTY_X86_FEATURE_1_AND) + && (GNU_PROPERTY_X86_FEATURE_1_AND + > GNU_PROPERTY_1_NEEDED)), "GNU_PROPERTY_X86_ISA_1_NEEDED > " - "GNU_PROPERTY_X86_FEATURE_1_AND"); + "GNU_PROPERTY_X86_FEATURE_1_AND && " + "GNU_PROPERTY_X86_FEATURE_1_AND > " + "GNU_PROPERTY_1_NEEDED"); if (type == GNU_PROPERTY_X86_FEATURE_1_AND) feature_1_and = *(unsigned int *) ptr; + else if (type == GNU_PROPERTY_1_NEEDED) + needed_1 = *(unsigned int *) ptr; else { isa_1_needed = *(unsigned int *) ptr; @@ -187,9 +195,10 @@ _dl_process_property_note (struct link_map *l, const ElfW(Nhdr) *note, } /* We get here only if there is one or no GNU property note. */ - if (isa_1_needed != 0 || feature_1_and != 0) + if (needed_1 != 0 || isa_1_needed != 0 || feature_1_and != 0) { l->l_property = lc_property_valid; + l->l_1_needed = needed_1; l->l_x86_isa_1_needed = isa_1_needed; l->l_x86_feature_1_and = feature_1_and; } diff --git a/sysdeps/x86/link_map.h b/sysdeps/x86/link_map.h index 4c46a25f83..0c7e25dc96 100644 --- a/sysdeps/x86/link_map.h +++ b/sysdeps/x86/link_map.h @@ -29,3 +29,5 @@ unsigned int l_x86_feature_1_and; /* GNU_PROPERTY_X86_ISA_1_NEEDED of this object. */ unsigned int l_x86_isa_1_needed; + +#include -- 2.11.4.GIT