The branch main has been updated by jhb:
URL:
https://cgit.FreeBSD.org/src/commit/?id=0cd42981dc0a180ced15265aa1658013a3de4dd4
commit 0cd42981dc0a180ced15265aa1658013a3de4dd4
Author: John Baldwin <j...@freebsd.org>
AuthorDate: 2025-08-22 13:58:51 +0000
Commit: John Baldwin <j...@freebsd.org>
CommitDate: 2025-08-22 13:58:51 +0000
imgact_elf: Add helper macros for name of the ELF ABI (elf32 vs elf64)
Reviewed by: brooks, kib
Obtained from: CheriBSD
Sponsored by: AFRL, DARPA
Differential Revision: https://reviews.freebsd.org/D52032
---
sys/kern/imgact_elf.c | 54 +++++++++++++++++++++++++++------------------------
1 file changed, 29 insertions(+), 25 deletions(-)
diff --git a/sys/kern/imgact_elf.c b/sys/kern/imgact_elf.c
index 2690ad3b2679..5a53fac50f2c 100644
--- a/sys/kern/imgact_elf.c
+++ b/sys/kern/imgact_elf.c
@@ -84,6 +84,13 @@
#define ELF_NOTE_ROUNDSIZE 4
#define OLD_EI_BRAND 8
+/*
+ * ELF_ABI_NAME is a string name of the ELF ABI. ELF_ABI_ID is used
+ * to build variable names.
+ */
+#define ELF_ABI_NAME __XSTRING(__CONCAT(ELF, __ELF_WORD_SIZE))
+#define ELF_ABI_ID __CONCAT(elf, __ELF_WORD_SIZE)
+
static int __elfN(check_header)(const Elf_Ehdr *hdr);
static Elf_Brandinfo *__elfN(get_brandinfo)(struct image_params *imgp,
const char *interp, int32_t *osrel, uint32_t *fctl0);
@@ -104,14 +111,15 @@ static Elf_Word __elfN(untrans_prot)(vm_prot_t);
static size_t __elfN(prepare_register_notes)(struct thread *td,
struct note_info_list *list, struct thread *target_td);
-SYSCTL_NODE(_kern, OID_AUTO, __CONCAT(elf, __ELF_WORD_SIZE),
- CTLFLAG_RW | CTLFLAG_MPSAFE, 0,
+SYSCTL_NODE(_kern, OID_AUTO, ELF_ABI_ID, CTLFLAG_RW | CTLFLAG_MPSAFE, 0,
"");
+#define ELF_NODE_OID __CONCAT(_kern_, ELF_ABI_ID)
+
int __elfN(fallback_brand) = -1;
-SYSCTL_INT(__CONCAT(_kern_elf, __ELF_WORD_SIZE), OID_AUTO,
+SYSCTL_INT(ELF_NODE_OID, OID_AUTO,
fallback_brand, CTLFLAG_RWTUN, &__elfN(fallback_brand), 0,
- __XSTRING(__CONCAT(ELF, __ELF_WORD_SIZE)) " brand of last resort");
+ ELF_ABI_NAME " brand of last resort");
static int elf_legacy_coredump = 0;
SYSCTL_INT(_debug, OID_AUTO, __elfN(legacy_coredump), CTLFLAG_RW,
@@ -126,22 +134,22 @@ int __elfN(nxstack) =
#else
0;
#endif
-SYSCTL_INT(__CONCAT(_kern_elf, __ELF_WORD_SIZE), OID_AUTO,
+SYSCTL_INT(ELF_NODE_OID, OID_AUTO,
nxstack, CTLFLAG_RW, &__elfN(nxstack), 0,
- __XSTRING(__CONCAT(ELF, __ELF_WORD_SIZE)) ": support PT_GNU_STACK for
non-executable stack control");
+ ELF_ABI_NAME ": support PT_GNU_STACK for non-executable stack control");
#if defined(__amd64__)
static int __elfN(vdso) = 1;
-SYSCTL_INT(__CONCAT(_kern_elf, __ELF_WORD_SIZE), OID_AUTO,
+SYSCTL_INT(ELF_NODE_OID, OID_AUTO,
vdso, CTLFLAG_RWTUN, &__elfN(vdso), 0,
- __XSTRING(__CONCAT(ELF, __ELF_WORD_SIZE)) ": enable vdso preloading");
+ ELF_ABI_NAME ": enable vdso preloading");
#else
static int __elfN(vdso) = 0;
#endif
#if __ELF_WORD_SIZE == 32 && (defined(__amd64__) || defined(__i386__))
int i386_read_exec = 0;
-SYSCTL_INT(_kern_elf32, OID_AUTO, read_exec, CTLFLAG_RW, &i386_read_exec, 0,
+SYSCTL_INT(ELF_NODE_OID, OID_AUTO, read_exec, CTLFLAG_RW, &i386_read_exec, 0,
"enable execution from readable segments");
#endif
@@ -161,15 +169,15 @@ sysctl_pie_base(SYSCTL_HANDLER_ARGS)
__elfN(pie_base) = val;
return (0);
}
-SYSCTL_PROC(__CONCAT(_kern_elf, __ELF_WORD_SIZE), OID_AUTO, pie_base,
+SYSCTL_PROC(ELF_NODE_OID, OID_AUTO, pie_base,
CTLTYPE_ULONG | CTLFLAG_MPSAFE | CTLFLAG_RW, NULL, 0,
sysctl_pie_base, "LU",
"PIE load base without randomization");
-SYSCTL_NODE(__CONCAT(_kern_elf, __ELF_WORD_SIZE), OID_AUTO, aslr,
+SYSCTL_NODE(ELF_NODE_OID, OID_AUTO, aslr,
CTLFLAG_RW | CTLFLAG_MPSAFE, 0,
"");
-#define ASLR_NODE_OID __CONCAT(__CONCAT(_kern_elf, __ELF_WORD_SIZE),
_aslr)
+#define ASLR_NODE_OID __CONCAT(ELF_NODE_OID, _aslr)
/*
* Enable ASLR by default for 64-bit non-PIE binaries. 32-bit architectures
@@ -179,8 +187,7 @@ SYSCTL_NODE(__CONCAT(_kern_elf, __ELF_WORD_SIZE), OID_AUTO,
aslr,
static int __elfN(aslr_enabled) = __ELF_WORD_SIZE == 64;
SYSCTL_INT(ASLR_NODE_OID, OID_AUTO, enable, CTLFLAG_RWTUN,
&__elfN(aslr_enabled), 0,
- __XSTRING(__CONCAT(ELF, __ELF_WORD_SIZE))
- ": enable address map randomization");
+ ELF_ABI_NAME ": enable address map randomization");
/*
* Enable ASLR by default for 64-bit PIE binaries.
@@ -188,8 +195,7 @@ SYSCTL_INT(ASLR_NODE_OID, OID_AUTO, enable, CTLFLAG_RWTUN,
static int __elfN(pie_aslr_enabled) = __ELF_WORD_SIZE == 64;
SYSCTL_INT(ASLR_NODE_OID, OID_AUTO, pie_enable, CTLFLAG_RWTUN,
&__elfN(pie_aslr_enabled), 0,
- __XSTRING(__CONCAT(ELF, __ELF_WORD_SIZE))
- ": enable address map randomization for PIE binaries");
+ ELF_ABI_NAME ": enable address map randomization for PIE binaries");
/*
* Sbrk is deprecated and it can be assumed that in most cases it will not be
@@ -199,27 +205,25 @@ SYSCTL_INT(ASLR_NODE_OID, OID_AUTO, pie_enable,
CTLFLAG_RWTUN,
static int __elfN(aslr_honor_sbrk) = 0;
SYSCTL_INT(ASLR_NODE_OID, OID_AUTO, honor_sbrk, CTLFLAG_RW,
&__elfN(aslr_honor_sbrk), 0,
- __XSTRING(__CONCAT(ELF, __ELF_WORD_SIZE)) ": assume sbrk is used");
+ ELF_ABI_NAME ": assume sbrk is used");
static int __elfN(aslr_stack) = __ELF_WORD_SIZE == 64;
SYSCTL_INT(ASLR_NODE_OID, OID_AUTO, stack, CTLFLAG_RWTUN,
&__elfN(aslr_stack), 0,
- __XSTRING(__CONCAT(ELF, __ELF_WORD_SIZE))
- ": enable stack address randomization");
+ ELF_ABI_NAME ": enable stack address randomization");
static int __elfN(aslr_shared_page) = __ELF_WORD_SIZE == 64;
SYSCTL_INT(ASLR_NODE_OID, OID_AUTO, shared_page, CTLFLAG_RWTUN,
&__elfN(aslr_shared_page), 0,
- __XSTRING(__CONCAT(ELF, __ELF_WORD_SIZE))
- ": enable shared page address randomization");
+ ELF_ABI_NAME ": enable shared page address randomization");
static int __elfN(sigfastblock) = 1;
-SYSCTL_INT(__CONCAT(_kern_elf, __ELF_WORD_SIZE), OID_AUTO, sigfastblock,
+SYSCTL_INT(ELF_NODE_OID, OID_AUTO, sigfastblock,
CTLFLAG_RWTUN, &__elfN(sigfastblock), 0,
"enable sigfastblock for new processes");
static bool __elfN(allow_wx) = true;
-SYSCTL_BOOL(__CONCAT(_kern_elf, __ELF_WORD_SIZE), OID_AUTO, allow_wx,
+SYSCTL_BOOL(ELF_NODE_OID, OID_AUTO, allow_wx,
CTLFLAG_RWTUN, &__elfN(allow_wx), 0,
"Allow pages to be mapped simultaneously writable and executable");
@@ -2951,9 +2955,9 @@ __elfN(check_note)(struct image_params *imgp,
Elf_Brandnote *brandnote,
*/
static struct execsw __elfN(execsw) = {
.ex_imgact = __CONCAT(exec_, __elfN(imgact)),
- .ex_name = __XSTRING(__CONCAT(ELF, __ELF_WORD_SIZE))
+ .ex_name = ELF_ABI_NAME
};
-EXEC_SET(__CONCAT(elf, __ELF_WORD_SIZE), __elfN(execsw));
+EXEC_SET(ELF_ABI_ID, __elfN(execsw));
static vm_prot_t
__elfN(trans_prot)(Elf_Word flags)
