Ok! After a ton of research and tracking down a bug in the mips64 implementation, I was finally able to recreate and subsequently fix this bug. I'll submit the updated patch shortly!
On Wed, Aug 24, 2022 at 5:10 PM Lance Fredrickson <[email protected]> wrote: > Hmm, wonder if small endian mips*el* has anything to do with it. > > I tried that patch on top of the other one and I get this error. > > mipsel-linux-g++ -static-pie hello.cpp -o hello > /opt/tomatoware/mipsel-soft-mmc/mipsel-tomatoware-linux-uclibc/sysroot/usr/lib/rcrt1.o: > in function `__start': > (.text+0x50): relocation truncated to fit: R_MIPS_PC16 against > `reloc_static_pie' > collect2: error: ld returned 1 exit status > > On 8/24/2022 1:23 PM, linted wrote: > > Hey Lance, > I'm having a bit of trouble recreating this bug. I do however have a > couple of possible solutions. Do you mind trying the following patch on top > of my previous one and letting me know if it solves the problem? > > --- > > diff --git a/libc/sysdeps/linux/mips/crt1.S > b/libc/sysdeps/linux/mips/crt1.S > index a7f72a90f..811b15387 100644 > --- a/libc/sysdeps/linux/mips/crt1.S > +++ b/libc/sysdeps/linux/mips/crt1.S > @@ -81,6 +81,7 @@ > #ifdef L_rcrt1 > .type reloc_static_pie,@function > .weak reloc_static_pie > + .hidden .L0 > #endif > .type main,@function > .type __uClibc_main,@function > @@ -97,8 +98,8 @@ __start: > #ifdef L_rcrt1 > PTR_LA $4, _DYNAMIC /* Place _DYNAMIC into the GOT */ > REG_S $4, -0x7ff0($28) > - jal L0 /* Get the current $pc address */ > -L0: > + jal .L0 /* Get the current $pc address */ > +.L0: > INT_SUB $25, $31, $25 /* Calculate load addr */ > move $4, $25 /* store load addr in param 1 */ > and $29, -2 * SZREG /* Ensure stack is aligned */ > > > On Mon, Aug 22, 2022 at 1:37 PM Lance Fredrickson <[email protected]> > wrote: > >> Gave this patch a go with patched gcc for -static-pie for mips. >> >> It works when compiling hello.c, but when I tried c++ hello.cpp program >> I get the following build error. >> >> mipsel-linux-g++ -s -static-pie hello.cpp -o hello >> /opt/tomatoware/mipsel-soft-mmc/mipsel-tomatoware-linux-uclibc/sysroot/usr/lib/rcrt1.o: >> >> in function `L0': >> (.text+0x50): relocation truncated to fit: R_MIPS_PC16 against >> `reloc_static_pie' >> collect2: error: ld returned 1 exit status >> >> Also tested arm with the new reworked patch and it seems to work for c >> and c++ hello world. >> >> Lance >> >> On 8/20/2022 10:32 PM, linted wrote: >> > Hello, >> > I have completed a patch to get static pie support working for the >> > mips architecture. >> > >> > Unfortunately a lot of the optimizations I made for previous >> > architectures needed to be rewritten in order to support the way that >> > mips works. There is a substantial rewrite of reloc_static_pie, >> > however the code is nearly a copy paste from dl-startup.c and has been >> > tested with all the currently supported architectures to ensure that >> > it still works. >> > >> > In order to compile with gcc, a patch for mips static pie is required. >> > I'm actively working on submitting said patch, but I do not have a >> > link for it yet. In the meantime, compilation using the following >> > flags passed to gcc should suffice. >> > >> > mips-linux-gcc -static-pie -Bstatic -pie --no-dynamic-linker -z text >> > input.c -o output >> > >> > ---- >> > From a6fa331c7ea16b5146c0d3ba3b2d6d723f09a9b4 Mon Sep 17 00:00:00 2001 >> > From: linted <[email protected]> >> > Date: Sat, 20 Aug 2022 16:41:38 -0400 >> > Subject: [PATCH] Added support for creation of Static >> Position-Independent >> > Executables (PIE) on mips >> > >> > Updated config to allow compilation of rcrt1.o for mips and modified >> > it's crt1.S to perform relocates in __start. >> > >> > The mips architecture performs relocations differently then most other >> > architectures. reloc_static_pie was rewritten, taking code from >> > dl-startup.c, in order to perform the additional relocations. >> > Modifications were made to mips' dl-startup.h to allow for the use of >> > contained macros without including _start definition. >> > >> > Signed-off-by: linted <[email protected]> >> > --- >> > extra/Configs/Config.in | 2 +- >> > ldso/ldso/mips/dl-startup.h | 3 +- >> > libc/misc/internals/Makefile.in | 2 +- >> > libc/misc/internals/reloc_static_pie.c | 91 ++++++++++++++++++++++---- >> > libc/sysdeps/linux/mips/crt1.S | 22 +++++++ >> > 5 files changed, 103 insertions(+), 17 deletions(-) >> > >> > diff --git a/extra/Configs/Config.in b/extra/Configs/Config.in >> > index e0905e956..43c04fd0a 100644 >> > --- a/extra/Configs/Config.in >> > +++ b/extra/Configs/Config.in >> > @@ -324,7 +324,7 @@ config DOPIC >> > config STATIC_PIE >> > bool "Add support for Static Position Independent Executables (PIE)" >> > default n >> > - depends on DOPIC && !UCLIBC_FORMAT_FDPIC_ELF && (TARGET_arm || >> > TARGET_i386 || TARGET_x86_64 || TARGET_aarch64) >> > + depends on DOPIC && !UCLIBC_FORMAT_FDPIC_ELF && (TARGET_arm || >> > TARGET_i386 || TARGET_x86_64 || TARGET_aarch64 || TARGET_mips) >> > >> > config ARCH_HAS_NO_SHARED >> > bool >> > diff --git a/ldso/ldso/mips/dl-startup.h b/ldso/ldso/mips/dl-startup.h >> > index 8026f1702..c2168d774 100644 >> > --- a/ldso/ldso/mips/dl-startup.h >> > +++ b/ldso/ldso/mips/dl-startup.h >> > @@ -7,6 +7,7 @@ >> > >> > >> > #include <sgidefs.h> >> > +#ifndef L_rcrt1 >> > __asm__("" >> > " .text\n" >> > " .globl _start\n" >> > @@ -114,6 +115,7 @@ __asm__("" >> > "\n\n" >> > ".previous\n" >> > ); >> > +#endif >> > >> > /* >> > * Get a pointer to the argv array. On many platforms this can be just >> > @@ -191,6 +193,5 @@ do { \ >> > case R_MIPS_NONE: \ >> > break; \ >> > default: \ >> > - SEND_STDERR("Aiieeee!"); \ >> > _dl_exit(1); \ >> > } >> > diff --git a/libc/misc/internals/Makefile.in >> > b/libc/misc/internals/Makefile.in >> > index 69af8b76e..908b18321 100644 >> > --- a/libc/misc/internals/Makefile.in >> > +++ b/libc/misc/internals/Makefile.in >> > @@ -17,7 +17,7 @@ MISC_INTERNALS_SRC := $(patsubst >> > %.c,$(MISC_INTERNALS_DIR)/%.c,$(CSRC-y)) >> > MISC_INTERNALS_OBJ := $(patsubst >> %.c,$(MISC_INTERNALS_OUT)/%.o,$(CSRC-y)) >> > >> > CFLAGS-__uClibc_main.c := $(SSP_DISABLE_FLAGS) >> > -CFLAGS-reloc_static_pie.c := $(SSP_DISABLE_FLAGS) >> > +CFLAGS-reloc_static_pie.c := $(SSP_DISABLE_FLAGS) -DL_rcrt1 >> > >> > libc-y += $(MISC_INTERNALS_OBJ) >> > ifneq ($(UCLIBC_FORMAT_SHARED_FLAT),y) >> > diff --git a/libc/misc/internals/reloc_static_pie.c >> > b/libc/misc/internals/reloc_static_pie.c >> > index 578202d23..cd9190d60 100644 >> > --- a/libc/misc/internals/reloc_static_pie.c >> > +++ b/libc/misc/internals/reloc_static_pie.c >> > @@ -20,28 +20,91 @@ >> > #include <elf.h> >> > #include <dl-elf.h> >> > >> > +#include <ldso.h> >> > +#ifdef __mips__ >> > +#include <dl-startup.h> >> > +#endif >> > + >> > ElfW(Addr) _dl_load_base = NULL; >> > >> > void >> > reloc_static_pie (ElfW(Addr) load_addr); >> > >> > void >> > -reloc_static_pie (ElfW(Addr) load_addr) >> > +reloc_static_pie(ElfW(Addr) load_addr) >> > { >> > - ElfW(Word) relative_count = 0; >> > - ElfW(Addr) rel_addr = 0; >> > - ElfW(Dyn) * dyn_addr = NULL; >> > - unsigned long dynamic_info[DYNAMIC_SIZE] = {0}; >> > + int indx; >> > + ElfW(Addr) got; >> > + ElfW(Dyn) *dpnt; >> > + struct elf_resolve tpnt_tmp; >> > + struct elf_resolve *tpnt = &tpnt_tmp; >> > + >> > + DL_BOOT_COMPUTE_GOT(got); >> > + DL_BOOT_COMPUTE_DYN(dpnt, got, (DL_LOADADDR_TYPE)load_addr); >> > + >> > + _dl_memset(tpnt, 0, sizeof(struct elf_resolve)); >> > + tpnt->loadaddr = load_addr; >> > + tpnt->dynamic_addr = dpnt; >> > + >> > + __dl_parse_dynamic_info(dpnt, tpnt->dynamic_info, NULL, load_addr); >> > + >> > +#if defined(PERFORM_BOOTSTRAP_GOT) >> > + /* some arches (like MIPS) we have to tweak the GOT before >> > relocations */ >> > + PERFORM_BOOTSTRAP_GOT(tpnt); >> > +#endif >> > + >> > + >> > +#if defined(ELF_MACHINE_PLTREL_OVERLAP) >> > +# define INDX_MAX 1 >> > +#else >> > +# define INDX_MAX 2 >> > +#endif >> > + >> > + for (indx = 0; indx < INDX_MAX; indx++) { >> > + unsigned long rel_addr, rel_size; >> > + ElfW(Word) relative_count = tpnt->dynamic_info[DT_RELCONT_IDX]; >> > + >> > + rel_addr = (indx ? tpnt->dynamic_info[DT_JMPREL] : >> > + tpnt->dynamic_info[DT_RELOC_TABLE_ADDR]); >> > + rel_size = (indx ? tpnt->dynamic_info[DT_PLTRELSZ] : >> > + tpnt->dynamic_info[DT_RELOC_TABLE_SIZE]); >> > + >> > + if (!rel_addr) >> > + continue; >> > >> > - /* Read our own dynamic section and fill in the info array. */ >> > - dyn_addr = ((void *) load_addr + elf_machine_dynamic ()); >> > + if((0 == indx) && relative_count) { >> > + rel_size -= relative_count * sizeof(ELF_RELOC); >> > + elf_machine_relative(load_addr, rel_addr, relative_count); >> > + rel_addr += relative_count * sizeof(ELF_RELOC); >> > + } >> > >> > - /* Use the underlying function to avoid TLS access before >> > initialization */ >> > - __dl_parse_dynamic_info(dyn_addr, dynamic_info, NULL, load_addr); >> > +#ifdef ARCH_NEEDS_BOOTSTRAP_RELOCS >> > + { >> > + ELF_RELOC *rpnt; >> > + unsigned int i; >> > + ElfW(Sym) *sym; >> > + unsigned long symbol_addr; >> > + int symtab_index; >> > + unsigned long *reloc_addr; >> > >> > - /* Perform relocations */ >> > - relative_count = dynamic_info[DT_RELCONT_IDX]; >> > - rel_addr = dynamic_info[DT_RELOC_TABLE_ADDR]; >> > - elf_machine_relative(load_addr, rel_addr, relative_count); >> > + /* Now parse the relocation information */ >> > + rpnt = (ELF_RELOC *) rel_addr; >> > + for (i = 0; i < rel_size; i += sizeof(ELF_RELOC), rpnt++) { >> > + reloc_addr = (unsigned long *) DL_RELOC_ADDR(load_addr, (unsigned >> > long)rpnt->r_offset); >> > + symtab_index = ELF_R_SYM(rpnt->r_info); >> > + symbol_addr = 0; >> > + sym = NULL; >> > + if (symtab_index) { >> > + ElfW(Sym) *symtab; >> > + symtab = (ElfW(Sym) *) tpnt->dynamic_info[DT_SYMTAB]; >> > + sym = &symtab[symtab_index]; >> > + symbol_addr = (unsigned long) DL_RELOC_ADDR(load_addr, sym->st_value); >> > + } >> > + /* Use this machine-specific macro to perform the actual relocation. >> */ >> > + PERFORM_BOOTSTRAP_RELOC(rpnt, reloc_addr, symbol_addr, load_addr, >> sym); >> > + } >> > + } >> > +#endif >> > + } >> > _dl_load_base = load_addr; >> > -} >> > +} >> > \ No newline at end of file >> > diff --git a/libc/sysdeps/linux/mips/crt1.S >> > b/libc/sysdeps/linux/mips/crt1.S >> > index 083615515..a7f72a90f 100644 >> > --- a/libc/sysdeps/linux/mips/crt1.S >> > +++ b/libc/sysdeps/linux/mips/crt1.S >> > @@ -77,6 +77,10 @@ >> > #ifndef __UCLIBC_CTOR_DTOR__ >> > .weak _init >> > .weak _fini >> > +#endif >> > +#ifdef L_rcrt1 >> > + .type reloc_static_pie,@function >> > + .weak reloc_static_pie >> > #endif >> > .type main,@function >> > .type __uClibc_main,@function >> > @@ -90,6 +94,24 @@ __start: >> > PTR_LA $28, _gp /* Setup GP correctly if we're non-PIC. >> */ >> > move $31, $0 >> > #endif >> > +#ifdef L_rcrt1 >> > + PTR_LA $4, _DYNAMIC /* Place _DYNAMIC into the GOT */ >> > + REG_S $4, -0x7ff0($28) >> > + jal L0 /* Get the current $pc address */ >> > +L0: >> > + INT_SUB $25, $31, $25 /* Calculate load addr */ >> > + move $4, $25 /* store load addr in param 1 */ >> > + and $29, -2 * SZREG /* Ensure stack is aligned */ >> > + addi $29, $29, (-2 * SZREG) /* Allocate 2 register spaces on stack >> */ >> > + REG_S $2, SZREG($29) /* Store atexit in case it exists */ >> > + PTR_LA $5, reloc_static_pie /* function calls before relocation >> > + don't work unless we set $t9 manually >> */ >> > + INT_ADDU $25, $25, $5 /* store reloc_static_pie in $t9 */ >> > + bal reloc_static_pie /* call, and pray the compiler adds a >> nop >> > + in delay slot */ >> > + REG_L $2, SZREG($29) /* cleanup stack */ >> > + addi $29, $29, (2 * SZREG) >> > +#endif >> > >> > PTR_LA $4, main /* main */ >> > PTR_L $5, 0($29) /* argc */ >> > -- >> > 2.34.1 >> > >> > >> > _______________________________________________ >> > devel mailing list -- [email protected] >> > To unsubscribe send an email to [email protected] >> >> _______________________________________________ >> devel mailing list -- [email protected] >> To unsubscribe send an email to [email protected] >> > >
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