Pass pointers to info parsed from notes, to brandinfo->header_supported filter.

Currently, we parse notes for the values of ELF FreeBSD feature flags
and osrel.  Knowing these values, or knowing that image does not carry
the note if pointers are NULL, is useful to decide which ABI variant
(brand) we want to activate for the image.

Right now this is only a plumbing change

Tested by:	pho
Sponsored by:	The FreeBSD Foundation
Differential revision:	https://reviews.freebsd.org/D25273
This commit is contained in:
Konstantin Belousov 2020-08-23 20:06:55 +00:00
parent e3cf75826d
commit 0cad2aa2dd
5 changed files with 37 additions and 19 deletions

View File

@ -56,7 +56,8 @@ __FBSDID("$FreeBSD$");
#include "opt_global.h" /* for OPT_KDTRACE_HOOKS */
#include "opt_stack.h" /* for OPT_STACK */
static boolean_t elf32_arm_abi_supported(struct image_params *);
static boolean_t elf32_arm_abi_supported(struct image_params *, int32_t *,
uint32_t *);
u_long elf_hwcap;
u_long elf_hwcap2;
@ -121,7 +122,8 @@ SYSINIT(elf32, SI_SUB_EXEC, SI_ORDER_FIRST,
&freebsd_brand_info);
static boolean_t
elf32_arm_abi_supported(struct image_params *imgp)
elf32_arm_abi_supported(struct image_params *imgp, int32_t *osrel __unused,
uint32_t *fctl0 __unused)
{
const Elf_Ehdr *hdr = (const Elf_Ehdr *)imgp->image_header;

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@ -69,7 +69,8 @@ static void freebsd32_setregs(struct thread *td, struct image_params *imgp,
u_long stack);
static void freebsd32_set_syscall_retval(struct thread *, int);
static boolean_t elf32_arm_abi_supported(struct image_params *);
static boolean_t elf32_arm_abi_supported(struct image_params *, int32_t *,
uint32_t *);
extern void freebsd32_sendsig(sig_t catcher, ksiginfo_t *ksi, sigset_t *mask);
@ -126,7 +127,8 @@ SYSINIT(elf32, SI_SUB_EXEC, SI_ORDER_FIRST,
(sysinit_cfunc_t)elf32_insert_brand_entry, &freebsd32_brand_info);
static boolean_t
elf32_arm_abi_supported(struct image_params *imgp)
elf32_arm_abi_supported(struct image_params *imgp, int32_t *osrel __unused,
uint32_t *fctl0 __unused)
{
const Elf32_Ehdr *hdr;

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@ -97,7 +97,8 @@ static bool __elfN(freebsd_trans_osrel)(const Elf_Note *note,
int32_t *osrel);
static bool kfreebsd_trans_osrel(const Elf_Note *note, int32_t *osrel);
static boolean_t __elfN(check_note)(struct image_params *imgp,
Elf_Brandnote *checknote, int32_t *osrel, uint32_t *fctl0);
Elf_Brandnote *checknote, int32_t *osrel, boolean_t *has_fctl0,
uint32_t *fctl0);
static vm_prot_t __elfN(trans_prot)(Elf_Word);
static Elf_Word __elfN(untrans_prot)(vm_prot_t);
@ -309,7 +310,7 @@ __elfN(get_brandinfo)(struct image_params *imgp, const char *interp,
{
const Elf_Ehdr *hdr = (const Elf_Ehdr *)imgp->image_header;
Elf_Brandinfo *bi, *bi_m;
boolean_t ret;
boolean_t ret, has_fctl0;
int i, interp_name_len;
interp_name_len = interp != NULL ? strlen(interp) + 1 : 0;
@ -331,11 +332,16 @@ __elfN(get_brandinfo)(struct image_params *imgp, const char *interp,
continue;
if (hdr->e_machine == bi->machine && (bi->flags &
(BI_BRAND_NOTE|BI_BRAND_NOTE_MANDATORY)) != 0) {
has_fctl0 = false;
*fctl0 = 0;
*osrel = 0;
ret = __elfN(check_note)(imgp, bi->brand_note, osrel,
fctl0);
&has_fctl0, fctl0);
/* Give brand a chance to veto check_note's guess */
if (ret && bi->header_supported)
ret = bi->header_supported(imgp);
if (ret && bi->header_supported) {
ret = bi->header_supported(imgp, osrel,
has_fctl0 ? fctl0 : NULL);
}
/*
* If note checker claimed the binary, but the
* interpreter path in the image does not
@ -374,7 +380,7 @@ __elfN(get_brandinfo)(struct image_params *imgp, const char *interp,
bi->compat_3_brand) == 0))) {
/* Looks good, but give brand a chance to veto */
if (bi->header_supported == NULL ||
bi->header_supported(imgp)) {
bi->header_supported(imgp, NULL, NULL)) {
/*
* Again, prefer strictly matching
* interpreter path.
@ -402,7 +408,7 @@ __elfN(get_brandinfo)(struct image_params *imgp, const char *interp,
bi->header_supported == NULL)
continue;
if (hdr->e_machine == bi->machine) {
ret = bi->header_supported(imgp);
ret = bi->header_supported(imgp, NULL, NULL);
if (ret)
return (bi);
}
@ -422,7 +428,7 @@ __elfN(get_brandinfo)(struct image_params *imgp, const char *interp,
strlen(bi->interp_path) + 1 == interp_name_len &&
strncmp(interp, bi->interp_path, interp_name_len)
== 0 && (bi->header_supported == NULL ||
bi->header_supported(imgp)))
bi->header_supported(imgp, NULL, NULL)))
return (bi);
}
}
@ -436,7 +442,7 @@ __elfN(get_brandinfo)(struct image_params *imgp, const char *interp,
if (hdr->e_machine == bi->machine &&
__elfN(fallback_brand) == bi->brand &&
(bi->header_supported == NULL ||
bi->header_supported(imgp)))
bi->header_supported(imgp, NULL, NULL)))
return (bi);
}
return (NULL);
@ -2657,6 +2663,7 @@ static Elf_Note fctl_note = {
};
struct fctl_cb_arg {
boolean_t *has_fctl0;
uint32_t *fctl0;
};
@ -2671,6 +2678,7 @@ note_fctl_cb(const Elf_Note *note, void *arg0, boolean_t *res)
p = (uintptr_t)(note + 1);
p += roundup2(note->n_namesz, ELF_NOTE_ROUNDSIZE);
desc = (const Elf32_Word *)p;
*arg->has_fctl0 = TRUE;
*arg->fctl0 = desc[0];
return (TRUE);
}
@ -2683,7 +2691,7 @@ note_fctl_cb(const Elf_Note *note, void *arg0, boolean_t *res)
*/
static boolean_t
__elfN(check_note)(struct image_params *imgp, Elf_Brandnote *brandnote,
int32_t *osrel, uint32_t *fctl0)
int32_t *osrel, boolean_t *has_fctl0, uint32_t *fctl0)
{
const Elf_Phdr *phdr;
const Elf_Ehdr *hdr;
@ -2695,6 +2703,7 @@ __elfN(check_note)(struct image_params *imgp, Elf_Brandnote *brandnote,
phdr = (const Elf_Phdr *)(imgp->image_header + hdr->e_phoff);
b_arg.brandnote = brandnote;
b_arg.osrel = osrel;
f_arg.has_fctl0 = has_fctl0;
f_arg.fctl0 = fctl0;
for (i = 0; i < hdr->e_phnum; i++) {

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@ -135,8 +135,10 @@ struct sysentvec elf64_freebsd_sysvec_v2 = {
};
INIT_SYSENTVEC(elf64_sysvec_v2, &elf64_freebsd_sysvec_v2);
static boolean_t ppc64_elfv1_header_match(struct image_params *params);
static boolean_t ppc64_elfv2_header_match(struct image_params *params);
static boolean_t ppc64_elfv1_header_match(struct image_params *params,
int32_t *, uint32_t *);
static boolean_t ppc64_elfv2_header_match(struct image_params *params,
int32_t *, uint32_t *);
static Elf64_Brandinfo freebsd_brand_info_elfv1 = {
.brand = ELFOSABI_FREEBSD,
@ -192,7 +194,8 @@ SYSINIT(oelf64, SI_SUB_EXEC, SI_ORDER_ANY,
void elf_reloc_self(Elf_Dyn *dynp, Elf_Addr relocbase);
static boolean_t
ppc64_elfv1_header_match(struct image_params *params)
ppc64_elfv1_header_match(struct image_params *params, int32_t *osrel __unused,
uint32_t *fctl0 __unused)
{
const Elf64_Ehdr *hdr = (const Elf64_Ehdr *)params->image_header;
int abi = (hdr->e_flags & 3);
@ -201,7 +204,8 @@ ppc64_elfv1_header_match(struct image_params *params)
}
static boolean_t
ppc64_elfv2_header_match(struct image_params *params)
ppc64_elfv2_header_match(struct image_params *params, int32_t *osrel __unused,
uint32_t *fctl0 __unused)
{
const Elf64_Ehdr *hdr = (const Elf64_Ehdr *)params->image_header;
int abi = (hdr->e_flags & 3);

View File

@ -87,7 +87,8 @@ typedef struct {
const char *interp_newpath;
int flags;
Elf_Brandnote *brand_note;
boolean_t (*header_supported)(struct image_params *);
boolean_t (*header_supported)(struct image_params *,
int32_t *, uint32_t *);
#define BI_CAN_EXEC_DYN 0x0001
#define BI_BRAND_NOTE 0x0002 /* May have note.ABI-tag section. */
#define BI_BRAND_NOTE_MANDATORY 0x0004 /* Must have note.ABI-tag section. */