* [PATCH 0/2] MIPS: module: Fixup error path & refactor
@ 2017-03-30 18:37 Paul Burton
2017-03-30 18:37 ` Paul Burton
` (2 more replies)
0 siblings, 3 replies; 6+ messages in thread
From: Paul Burton @ 2017-03-30 18:37 UTC (permalink / raw)
To: linux-mips, Ralf Baechle; +Cc: Paul Burton
This short series fixes a memory leak in the error path of
apply_relocate(), and refactors the REL & RELA style reloc handling to
allow for the sharing of code between the two & the removal of a fair
amount of duplication.
Applies atop v4.11-rc4.
Paul Burton (2):
MIPS: module: Ensure we always clean up r_mips_hi16_list
MIPS: module: Unify rel & rela reloc handling
arch/mips/include/asm/module.h | 8 +-
arch/mips/kernel/Makefile | 1 -
arch/mips/kernel/module-rela.c | 202 -------------------------------------
arch/mips/kernel/module.c | 221 ++++++++++++++++++++++++++++++-----------
4 files changed, 169 insertions(+), 263 deletions(-)
delete mode 100644 arch/mips/kernel/module-rela.c
--
2.12.1
^ permalink raw reply [flat|nested] 6+ messages in thread* [PATCH 0/2] MIPS: module: Fixup error path & refactor 2017-03-30 18:37 [PATCH 0/2] MIPS: module: Fixup error path & refactor Paul Burton @ 2017-03-30 18:37 ` Paul Burton 2017-03-30 18:37 ` [PATCH 1/2] MIPS: module: Ensure we always clean up r_mips_hi16_list Paul Burton 2017-03-30 18:37 ` [PATCH 2/2] MIPS: module: Unify rel & rela reloc handling Paul Burton 2 siblings, 0 replies; 6+ messages in thread From: Paul Burton @ 2017-03-30 18:37 UTC (permalink / raw) To: linux-mips, Ralf Baechle; +Cc: Paul Burton This short series fixes a memory leak in the error path of apply_relocate(), and refactors the REL & RELA style reloc handling to allow for the sharing of code between the two & the removal of a fair amount of duplication. Applies atop v4.11-rc4. Paul Burton (2): MIPS: module: Ensure we always clean up r_mips_hi16_list MIPS: module: Unify rel & rela reloc handling arch/mips/include/asm/module.h | 8 +- arch/mips/kernel/Makefile | 1 - arch/mips/kernel/module-rela.c | 202 ------------------------------------- arch/mips/kernel/module.c | 221 ++++++++++++++++++++++++++++++----------- 4 files changed, 169 insertions(+), 263 deletions(-) delete mode 100644 arch/mips/kernel/module-rela.c -- 2.12.1 ^ permalink raw reply [flat|nested] 6+ messages in thread
* [PATCH 1/2] MIPS: module: Ensure we always clean up r_mips_hi16_list 2017-03-30 18:37 [PATCH 0/2] MIPS: module: Fixup error path & refactor Paul Burton 2017-03-30 18:37 ` Paul Burton @ 2017-03-30 18:37 ` Paul Burton 2017-03-30 18:37 ` Paul Burton 2017-03-30 18:37 ` [PATCH 2/2] MIPS: module: Unify rel & rela reloc handling Paul Burton 2 siblings, 1 reply; 6+ messages in thread From: Paul Burton @ 2017-03-30 18:37 UTC (permalink / raw) To: linux-mips, Ralf Baechle; +Cc: Paul Burton If we hit an error whilst processing a reloc then we would return early from apply_relocate & potentially not free entries in r_mips_hi16_list, thereby leaking memory. Fix this by ensuring that we always run the code to free r_mipps_hi16_list when errors occur. Signed-off-by: Paul Burton <paul.burton@imgtec.com> Fixes: 861667dc82f5 ("MIPS: Fix race condition in module relocation code.") Fixes: 04211a574641 ("MIPS: Bail on unsupported module relocs") Cc: linux-mips@linux-mips.org Cc: Ralf Baechle <ralf@linux-mips.org> --- arch/mips/kernel/module.c | 28 ++++++++++++++++------------ 1 file changed, 16 insertions(+), 12 deletions(-) diff --git a/arch/mips/kernel/module.c b/arch/mips/kernel/module.c index 94627a3a6a0d..ddcfb59593b6 100644 --- a/arch/mips/kernel/module.c +++ b/arch/mips/kernel/module.c @@ -251,7 +251,7 @@ int apply_relocate(Elf_Shdr *sechdrs, const char *strtab, u32 *location; unsigned int i, type; Elf_Addr v; - int res; + int err = 0; pr_debug("Applying relocate section %u to %u\n", relsec, sechdrs[relsec].sh_info); @@ -270,7 +270,8 @@ int apply_relocate(Elf_Shdr *sechdrs, const char *strtab, continue; pr_warn("%s: Unknown symbol %s\n", me->name, strtab + sym->st_name); - return -ENOENT; + err = -ENOENT; + goto out; } type = ELF_MIPS_R_TYPE(rel[i]); @@ -283,29 +284,32 @@ int apply_relocate(Elf_Shdr *sechdrs, const char *strtab, if (!handler) { pr_err("%s: Unknown relocation type %u\n", me->name, type); - return -EINVAL; + err = -EINVAL; + goto out; } v = sym->st_value; - res = handler(me, location, v); - if (res) - return res; + err = handler(me, location, v); + if (err) + goto out; } +out: /* - * Normally the hi16 list should be deallocated at this point. A + * Normally the hi16 list should be deallocated at this point. A * malformed binary however could contain a series of R_MIPS_HI16 - * relocations not followed by a R_MIPS_LO16 relocation. In that - * case, free up the list and return an error. + * relocations not followed by a R_MIPS_LO16 relocation, or if we hit + * an error processing a reloc we might have gotten here before + * reaching the R_MIPS_LO16. In either case, free up the list and + * return an error. */ if (me->arch.r_mips_hi16_list) { free_relocation_chain(me->arch.r_mips_hi16_list); me->arch.r_mips_hi16_list = NULL; - - return -ENOEXEC; + err = err ?: -ENOEXEC; } - return 0; + return err; } /* Given an address, look for it in the module exception tables. */ -- 2.12.1 ^ permalink raw reply related [flat|nested] 6+ messages in thread
* [PATCH 1/2] MIPS: module: Ensure we always clean up r_mips_hi16_list 2017-03-30 18:37 ` [PATCH 1/2] MIPS: module: Ensure we always clean up r_mips_hi16_list Paul Burton @ 2017-03-30 18:37 ` Paul Burton 0 siblings, 0 replies; 6+ messages in thread From: Paul Burton @ 2017-03-30 18:37 UTC (permalink / raw) To: linux-mips, Ralf Baechle; +Cc: Paul Burton If we hit an error whilst processing a reloc then we would return early from apply_relocate & potentially not free entries in r_mips_hi16_list, thereby leaking memory. Fix this by ensuring that we always run the code to free r_mipps_hi16_list when errors occur. Signed-off-by: Paul Burton <paul.burton@imgtec.com> Fixes: 861667dc82f5 ("MIPS: Fix race condition in module relocation code.") Fixes: 04211a574641 ("MIPS: Bail on unsupported module relocs") Cc: linux-mips@linux-mips.org Cc: Ralf Baechle <ralf@linux-mips.org> --- arch/mips/kernel/module.c | 28 ++++++++++++++++------------ 1 file changed, 16 insertions(+), 12 deletions(-) diff --git a/arch/mips/kernel/module.c b/arch/mips/kernel/module.c index 94627a3a6a0d..ddcfb59593b6 100644 --- a/arch/mips/kernel/module.c +++ b/arch/mips/kernel/module.c @@ -251,7 +251,7 @@ int apply_relocate(Elf_Shdr *sechdrs, const char *strtab, u32 *location; unsigned int i, type; Elf_Addr v; - int res; + int err = 0; pr_debug("Applying relocate section %u to %u\n", relsec, sechdrs[relsec].sh_info); @@ -270,7 +270,8 @@ int apply_relocate(Elf_Shdr *sechdrs, const char *strtab, continue; pr_warn("%s: Unknown symbol %s\n", me->name, strtab + sym->st_name); - return -ENOENT; + err = -ENOENT; + goto out; } type = ELF_MIPS_R_TYPE(rel[i]); @@ -283,29 +284,32 @@ int apply_relocate(Elf_Shdr *sechdrs, const char *strtab, if (!handler) { pr_err("%s: Unknown relocation type %u\n", me->name, type); - return -EINVAL; + err = -EINVAL; + goto out; } v = sym->st_value; - res = handler(me, location, v); - if (res) - return res; + err = handler(me, location, v); + if (err) + goto out; } +out: /* - * Normally the hi16 list should be deallocated at this point. A + * Normally the hi16 list should be deallocated at this point. A * malformed binary however could contain a series of R_MIPS_HI16 - * relocations not followed by a R_MIPS_LO16 relocation. In that - * case, free up the list and return an error. + * relocations not followed by a R_MIPS_LO16 relocation, or if we hit + * an error processing a reloc we might have gotten here before + * reaching the R_MIPS_LO16. In either case, free up the list and + * return an error. */ if (me->arch.r_mips_hi16_list) { free_relocation_chain(me->arch.r_mips_hi16_list); me->arch.r_mips_hi16_list = NULL; - - return -ENOEXEC; + err = err ?: -ENOEXEC; } - return 0; + return err; } /* Given an address, look for it in the module exception tables. */ -- 2.12.1 ^ permalink raw reply related [flat|nested] 6+ messages in thread
* [PATCH 2/2] MIPS: module: Unify rel & rela reloc handling 2017-03-30 18:37 [PATCH 0/2] MIPS: module: Fixup error path & refactor Paul Burton 2017-03-30 18:37 ` Paul Burton 2017-03-30 18:37 ` [PATCH 1/2] MIPS: module: Ensure we always clean up r_mips_hi16_list Paul Burton @ 2017-03-30 18:37 ` Paul Burton 2017-03-30 18:37 ` Paul Burton 2 siblings, 1 reply; 6+ messages in thread From: Paul Burton @ 2017-03-30 18:37 UTC (permalink / raw) To: linux-mips, Ralf Baechle; +Cc: Paul Burton The module load code has previously had entirely separate implementations for rel & rela style relocs, which unnecessarily duplicates a whole lot of code. Unify the implementations of both types of reloc, sharing the bulk of the code. Signed-off-by: Paul Burton <paul.burton@imgtec.com> Cc: linux-mips@linux-mips.org Cc: Ralf Baechle <ralf@linux-mips.org> --- arch/mips/include/asm/module.h | 8 +- arch/mips/kernel/Makefile | 1 - arch/mips/kernel/module-rela.c | 202 ----------------------------------------- arch/mips/kernel/module.c | 195 ++++++++++++++++++++++++++++++--------- 4 files changed, 154 insertions(+), 252 deletions(-) delete mode 100644 arch/mips/kernel/module-rela.c diff --git a/arch/mips/include/asm/module.h b/arch/mips/include/asm/module.h index 702c273e67a9..e51add184717 100644 --- a/arch/mips/include/asm/module.h +++ b/arch/mips/include/asm/module.h @@ -47,8 +47,8 @@ typedef struct { #define Elf_Mips_Rel Elf32_Rel #define Elf_Mips_Rela Elf32_Rela -#define ELF_MIPS_R_SYM(rel) ELF32_R_SYM(rel.r_info) -#define ELF_MIPS_R_TYPE(rel) ELF32_R_TYPE(rel.r_info) +#define ELF_MIPS_R_SYM(rel) ELF32_R_SYM((rel).r_info) +#define ELF_MIPS_R_TYPE(rel) ELF32_R_TYPE((rel).r_info) #endif @@ -65,8 +65,8 @@ typedef struct { #define Elf_Mips_Rel Elf64_Mips_Rel #define Elf_Mips_Rela Elf64_Mips_Rela -#define ELF_MIPS_R_SYM(rel) (rel.r_sym) -#define ELF_MIPS_R_TYPE(rel) (rel.r_type) +#define ELF_MIPS_R_SYM(rel) ((rel).r_sym) +#define ELF_MIPS_R_TYPE(rel) ((rel).r_type) #endif diff --git a/arch/mips/kernel/Makefile b/arch/mips/kernel/Makefile index 9a0e37b92ce0..f0edd7e8a0b7 100644 --- a/arch/mips/kernel/Makefile +++ b/arch/mips/kernel/Makefile @@ -31,7 +31,6 @@ obj-$(CONFIG_SYNC_R4K) += sync-r4k.o obj-$(CONFIG_DEBUG_FS) += segment.o obj-$(CONFIG_STACKTRACE) += stacktrace.o obj-$(CONFIG_MODULES) += module.o -obj-$(CONFIG_MODULES_USE_ELF_RELA) += module-rela.o obj-$(CONFIG_FTRACE_SYSCALLS) += ftrace.o obj-$(CONFIG_FUNCTION_TRACER) += mcount.o ftrace.o diff --git a/arch/mips/kernel/module-rela.c b/arch/mips/kernel/module-rela.c deleted file mode 100644 index 781168834456..000000000000 --- a/arch/mips/kernel/module-rela.c +++ /dev/null @@ -1,202 +0,0 @@ -/* - * This program is free software; you can redistribute it and/or modify - * it under the terms of the GNU General Public License as published by - * the Free Software Foundation; either version 2 of the License, or - * (at your option) any later version. - * - * This program is distributed in the hope that it will be useful, - * but WITHOUT ANY WARRANTY; without even the implied warranty of - * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the - * GNU General Public License for more details. - * - * You should have received a copy of the GNU General Public License - * along with this program; if not, write to the Free Software - * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA - * - * Copyright (C) 2001 Rusty Russell. - * Copyright (C) 2003, 2004 Ralf Baechle (ralf@linux-mips.org) - * Copyright (C) 2005 Thiemo Seufer - * Copyright (C) 2015 Imagination Technologies Ltd. - */ - -#include <linux/elf.h> -#include <linux/err.h> -#include <linux/errno.h> -#include <linux/moduleloader.h> - -extern int apply_r_mips_none(struct module *me, u32 *location, Elf_Addr v); - -static int apply_r_mips_32_rela(struct module *me, u32 *location, Elf_Addr v) -{ - *location = v; - - return 0; -} - -static int apply_r_mips_26_rela(struct module *me, u32 *location, Elf_Addr v) -{ - if (v % 4) { - pr_err("module %s: dangerous R_MIPS_26 RELA relocation\n", - me->name); - return -ENOEXEC; - } - - if ((v & 0xf0000000) != (((unsigned long)location + 4) & 0xf0000000)) { - pr_err("module %s: relocation overflow\n", me->name); - return -ENOEXEC; - } - - *location = (*location & ~0x03ffffff) | ((v >> 2) & 0x03ffffff); - - return 0; -} - -static int apply_r_mips_hi16_rela(struct module *me, u32 *location, Elf_Addr v) -{ - *location = (*location & 0xffff0000) | - ((((long long) v + 0x8000LL) >> 16) & 0xffff); - - return 0; -} - -static int apply_r_mips_lo16_rela(struct module *me, u32 *location, Elf_Addr v) -{ - *location = (*location & 0xffff0000) | (v & 0xffff); - - return 0; -} - -static int apply_r_mips_pc_rela(struct module *me, u32 *location, Elf_Addr v, - unsigned bits) -{ - unsigned long mask = GENMASK(bits - 1, 0); - unsigned long se_bits; - long offset; - - if (v % 4) { - pr_err("module %s: dangerous R_MIPS_PC%u RELA relocation\n", - me->name, bits); - return -ENOEXEC; - } - - offset = ((long)v - (long)location) >> 2; - - /* check the sign bit onwards are identical - ie. we didn't overflow */ - se_bits = (offset & BIT(bits - 1)) ? ~0ul : 0; - if ((offset & ~mask) != (se_bits & ~mask)) { - pr_err("module %s: relocation overflow\n", me->name); - return -ENOEXEC; - } - - *location = (*location & ~mask) | (offset & mask); - - return 0; -} - -static int apply_r_mips_pc16_rela(struct module *me, u32 *location, Elf_Addr v) -{ - return apply_r_mips_pc_rela(me, location, v, 16); -} - -static int apply_r_mips_pc21_rela(struct module *me, u32 *location, Elf_Addr v) -{ - return apply_r_mips_pc_rela(me, location, v, 21); -} - -static int apply_r_mips_pc26_rela(struct module *me, u32 *location, Elf_Addr v) -{ - return apply_r_mips_pc_rela(me, location, v, 26); -} - -static int apply_r_mips_64_rela(struct module *me, u32 *location, Elf_Addr v) -{ - *(Elf_Addr *)location = v; - - return 0; -} - -static int apply_r_mips_higher_rela(struct module *me, u32 *location, - Elf_Addr v) -{ - *location = (*location & 0xffff0000) | - ((((long long) v + 0x80008000LL) >> 32) & 0xffff); - - return 0; -} - -static int apply_r_mips_highest_rela(struct module *me, u32 *location, - Elf_Addr v) -{ - *location = (*location & 0xffff0000) | - ((((long long) v + 0x800080008000LL) >> 48) & 0xffff); - - return 0; -} - -static int (*reloc_handlers_rela[]) (struct module *me, u32 *location, - Elf_Addr v) = { - [R_MIPS_NONE] = apply_r_mips_none, - [R_MIPS_32] = apply_r_mips_32_rela, - [R_MIPS_26] = apply_r_mips_26_rela, - [R_MIPS_HI16] = apply_r_mips_hi16_rela, - [R_MIPS_LO16] = apply_r_mips_lo16_rela, - [R_MIPS_PC16] = apply_r_mips_pc16_rela, - [R_MIPS_64] = apply_r_mips_64_rela, - [R_MIPS_HIGHER] = apply_r_mips_higher_rela, - [R_MIPS_HIGHEST] = apply_r_mips_highest_rela, - [R_MIPS_PC21_S2] = apply_r_mips_pc21_rela, - [R_MIPS_PC26_S2] = apply_r_mips_pc26_rela, -}; - -int apply_relocate_add(Elf_Shdr *sechdrs, const char *strtab, - unsigned int symindex, unsigned int relsec, - struct module *me) -{ - Elf_Mips_Rela *rel = (void *) sechdrs[relsec].sh_addr; - int (*handler)(struct module *me, u32 *location, Elf_Addr v); - Elf_Sym *sym; - u32 *location; - unsigned int i, type; - Elf_Addr v; - int res; - - pr_debug("Applying relocate section %u to %u\n", relsec, - sechdrs[relsec].sh_info); - - for (i = 0; i < sechdrs[relsec].sh_size / sizeof(*rel); i++) { - /* This is where to make the change */ - location = (void *)sechdrs[sechdrs[relsec].sh_info].sh_addr - + rel[i].r_offset; - /* This is the symbol it is referring to */ - sym = (Elf_Sym *)sechdrs[symindex].sh_addr - + ELF_MIPS_R_SYM(rel[i]); - if (sym->st_value >= -MAX_ERRNO) { - /* Ignore unresolved weak symbol */ - if (ELF_ST_BIND(sym->st_info) == STB_WEAK) - continue; - pr_warn("%s: Unknown symbol %s\n", - me->name, strtab + sym->st_name); - return -ENOENT; - } - - type = ELF_MIPS_R_TYPE(rel[i]); - - if (type < ARRAY_SIZE(reloc_handlers_rela)) - handler = reloc_handlers_rela[type]; - else - handler = NULL; - - if (!handler) { - pr_err("%s: Unknown relocation type %u\n", - me->name, type); - return -EINVAL; - } - - v = sym->st_value + rel[i].r_addend; - res = handler(me, location, v); - if (res) - return res; - } - - return 0; -} diff --git a/arch/mips/kernel/module.c b/arch/mips/kernel/module.c index ddcfb59593b6..b250eb0c4fc1 100644 --- a/arch/mips/kernel/module.c +++ b/arch/mips/kernel/module.c @@ -53,22 +53,25 @@ void *module_alloc(unsigned long size) } #endif -int apply_r_mips_none(struct module *me, u32 *location, Elf_Addr v) +static int apply_r_mips_none(struct module *me, u32 *location, + u32 base, Elf_Addr v, bool rela) { return 0; } -static int apply_r_mips_32_rel(struct module *me, u32 *location, Elf_Addr v) +static int apply_r_mips_32(struct module *me, u32 *location, + u32 base, Elf_Addr v, bool rela) { - *location += v; + *location = base + v; return 0; } -static int apply_r_mips_26_rel(struct module *me, u32 *location, Elf_Addr v) +static int apply_r_mips_26(struct module *me, u32 *location, + u32 base, Elf_Addr v, bool rela) { if (v % 4) { - pr_err("module %s: dangerous R_MIPS_26 REL relocation\n", + pr_err("module %s: dangerous R_MIPS_26 relocation\n", me->name); return -ENOEXEC; } @@ -80,15 +83,22 @@ static int apply_r_mips_26_rel(struct module *me, u32 *location, Elf_Addr v) } *location = (*location & ~0x03ffffff) | - ((*location + (v >> 2)) & 0x03ffffff); + ((base + (v >> 2)) & 0x03ffffff); return 0; } -static int apply_r_mips_hi16_rel(struct module *me, u32 *location, Elf_Addr v) +static int apply_r_mips_hi16(struct module *me, u32 *location, + u32 base, Elf_Addr v, bool rela) { struct mips_hi16 *n; + if (rela) { + *location = (*location & 0xffff0000) | + ((((long long) v + 0x8000LL) >> 16) & 0xffff); + return 0; + } + /* * We cannot relocate this one now because we don't know the value of * the carry we need to add. Save the information, and let LO16 do the @@ -117,12 +127,18 @@ static void free_relocation_chain(struct mips_hi16 *l) } } -static int apply_r_mips_lo16_rel(struct module *me, u32 *location, Elf_Addr v) +static int apply_r_mips_lo16(struct module *me, u32 *location, + u32 base, Elf_Addr v, bool rela) { - unsigned long insnlo = *location; + unsigned long insnlo = base; struct mips_hi16 *l; Elf_Addr val, vallo; + if (rela) { + *location = (*location & 0xffff0000) | (v & 0xffff); + return 0; + } + /* Sign extend the addend we extract from the lo insn. */ vallo = ((insnlo & 0xffff) ^ 0x8000) - 0x8000; @@ -178,26 +194,26 @@ static int apply_r_mips_lo16_rel(struct module *me, u32 *location, Elf_Addr v) free_relocation_chain(l); me->arch.r_mips_hi16_list = NULL; - pr_err("module %s: dangerous R_MIPS_LO16 REL relocation\n", me->name); + pr_err("module %s: dangerous R_MIPS_LO16 relocation\n", me->name); return -ENOEXEC; } -static int apply_r_mips_pc_rel(struct module *me, u32 *location, Elf_Addr v, - unsigned bits) +static int apply_r_mips_pc(struct module *me, u32 *location, u32 base, + Elf_Addr v, unsigned int bits) { unsigned long mask = GENMASK(bits - 1, 0); unsigned long se_bits; long offset; if (v % 4) { - pr_err("module %s: dangerous R_MIPS_PC%u REL relocation\n", + pr_err("module %s: dangerous R_MIPS_PC%u relocation\n", me->name, bits); return -ENOEXEC; } - /* retrieve & sign extend implicit addend */ - offset = *location & mask; + /* retrieve & sign extend implicit addend if any */ + offset = base & mask; offset |= (offset & BIT(bits - 1)) ? ~mask : 0; offset += ((long)v - (long)location) >> 2; @@ -214,56 +230,121 @@ static int apply_r_mips_pc_rel(struct module *me, u32 *location, Elf_Addr v, return 0; } -static int apply_r_mips_pc16_rel(struct module *me, u32 *location, Elf_Addr v) +static int apply_r_mips_pc16(struct module *me, u32 *location, + u32 base, Elf_Addr v, bool rela) { - return apply_r_mips_pc_rel(me, location, v, 16); + return apply_r_mips_pc(me, location, base, v, 16); } -static int apply_r_mips_pc21_rel(struct module *me, u32 *location, Elf_Addr v) +static int apply_r_mips_pc21(struct module *me, u32 *location, + u32 base, Elf_Addr v, bool rela) { - return apply_r_mips_pc_rel(me, location, v, 21); + return apply_r_mips_pc(me, location, base, v, 21); } -static int apply_r_mips_pc26_rel(struct module *me, u32 *location, Elf_Addr v) +static int apply_r_mips_pc26(struct module *me, u32 *location, + u32 base, Elf_Addr v, bool rela) { - return apply_r_mips_pc_rel(me, location, v, 26); + return apply_r_mips_pc(me, location, base, v, 26); } -static int (*reloc_handlers_rel[]) (struct module *me, u32 *location, - Elf_Addr v) = { +static int apply_r_mips_64(struct module *me, u32 *location, + u32 base, Elf_Addr v, bool rela) +{ + if (WARN_ON(!rela)) + return -EINVAL; + + *(Elf_Addr *)location = v; + + return 0; +} + +static int apply_r_mips_higher(struct module *me, u32 *location, + u32 base, Elf_Addr v, bool rela) +{ + if (WARN_ON(!rela)) + return -EINVAL; + + *location = (*location & 0xffff0000) | + ((((long long)v + 0x80008000LL) >> 32) & 0xffff); + + return 0; +} + +static int apply_r_mips_highest(struct module *me, u32 *location, + u32 base, Elf_Addr v, bool rela) +{ + if (WARN_ON(!rela)) + return -EINVAL; + + *location = (*location & 0xffff0000) | + ((((long long)v + 0x800080008000LL) >> 48) & 0xffff); + + return 0; +} + +/** + * reloc_handler() - Apply a particular relocation to a module + * @me: the module to apply the reloc to + * @location: the address at which the reloc is to be applied + * @base: the existing value at location for REL-style; 0 for RELA-style + * @v: the value of the reloc, with addend for RELA-style + * + * Each implemented reloc_handler function applies a particular type of + * relocation to the module @me. Relocs that may be found in either REL or RELA + * variants can be handled by making use of the @base & @v parameters which are + * set to values which abstract the difference away from the particular reloc + * implementations. + * + * Return: 0 upon success, else -ERRNO + */ +typedef int (*reloc_handler)(struct module *me, u32 *location, + u32 base, Elf_Addr v, bool rela); + +/* The handlers for known reloc types */ +static reloc_handler reloc_handlers[] = { [R_MIPS_NONE] = apply_r_mips_none, - [R_MIPS_32] = apply_r_mips_32_rel, - [R_MIPS_26] = apply_r_mips_26_rel, - [R_MIPS_HI16] = apply_r_mips_hi16_rel, - [R_MIPS_LO16] = apply_r_mips_lo16_rel, - [R_MIPS_PC16] = apply_r_mips_pc16_rel, - [R_MIPS_PC21_S2] = apply_r_mips_pc21_rel, - [R_MIPS_PC26_S2] = apply_r_mips_pc26_rel, + [R_MIPS_32] = apply_r_mips_32, + [R_MIPS_26] = apply_r_mips_26, + [R_MIPS_HI16] = apply_r_mips_hi16, + [R_MIPS_LO16] = apply_r_mips_lo16, + [R_MIPS_PC16] = apply_r_mips_pc16, + [R_MIPS_64] = apply_r_mips_64, + [R_MIPS_HIGHER] = apply_r_mips_higher, + [R_MIPS_HIGHEST] = apply_r_mips_highest, + [R_MIPS_PC21_S2] = apply_r_mips_pc21, + [R_MIPS_PC26_S2] = apply_r_mips_pc26, }; -int apply_relocate(Elf_Shdr *sechdrs, const char *strtab, - unsigned int symindex, unsigned int relsec, - struct module *me) +static int __apply_relocate(Elf_Shdr *sechdrs, const char *strtab, + unsigned int symindex, unsigned int relsec, + struct module *me, bool rela) { - Elf_Mips_Rel *rel = (void *) sechdrs[relsec].sh_addr; - int (*handler)(struct module *me, u32 *location, Elf_Addr v); + union { + Elf_Mips_Rel *rel; + Elf_Mips_Rela *rela; + } r; + reloc_handler handler; Elf_Sym *sym; - u32 *location; + u32 *location, base; unsigned int i, type; Elf_Addr v; int err = 0; + size_t reloc_sz; pr_debug("Applying relocate section %u to %u\n", relsec, sechdrs[relsec].sh_info); + r.rel = (void *)sechdrs[relsec].sh_addr; + reloc_sz = rela ? sizeof(*r.rela) : sizeof(*r.rel); me->arch.r_mips_hi16_list = NULL; - for (i = 0; i < sechdrs[relsec].sh_size / sizeof(*rel); i++) { + for (i = 0; i < sechdrs[relsec].sh_size / reloc_sz; i++) { /* This is where to make the change */ location = (void *)sechdrs[sechdrs[relsec].sh_info].sh_addr - + rel[i].r_offset; + + r.rel->r_offset; /* This is the symbol it is referring to */ sym = (Elf_Sym *)sechdrs[symindex].sh_addr - + ELF_MIPS_R_SYM(rel[i]); + + ELF_MIPS_R_SYM(*r.rel); if (sym->st_value >= -MAX_ERRNO) { /* Ignore unresolved weak symbol */ if (ELF_ST_BIND(sym->st_info) == STB_WEAK) @@ -274,10 +355,9 @@ int apply_relocate(Elf_Shdr *sechdrs, const char *strtab, goto out; } - type = ELF_MIPS_R_TYPE(rel[i]); - - if (type < ARRAY_SIZE(reloc_handlers_rel)) - handler = reloc_handlers_rel[type]; + type = ELF_MIPS_R_TYPE(*r.rel); + if (type < ARRAY_SIZE(reloc_handlers)) + handler = reloc_handlers[type]; else handler = NULL; @@ -288,8 +368,17 @@ int apply_relocate(Elf_Shdr *sechdrs, const char *strtab, goto out; } - v = sym->st_value; - err = handler(me, location, v); + if (rela) { + v = sym->st_value + r.rela->r_addend; + base = 0; + r.rela = &r.rela[1]; + } else { + v = sym->st_value; + base = *location; + r.rel = &r.rel[1]; + } + + err = handler(me, location, base, v, rela); if (err) goto out; } @@ -312,6 +401,22 @@ int apply_relocate(Elf_Shdr *sechdrs, const char *strtab, return err; } +int apply_relocate(Elf_Shdr *sechdrs, const char *strtab, + unsigned int symindex, unsigned int relsec, + struct module *me) +{ + return __apply_relocate(sechdrs, strtab, symindex, relsec, me, false); +} + +#ifdef CONFIG_MODULES_USE_ELF_RELA +int apply_relocate_add(Elf_Shdr *sechdrs, const char *strtab, + unsigned int symindex, unsigned int relsec, + struct module *me) +{ + return __apply_relocate(sechdrs, strtab, symindex, relsec, me, true); +} +#endif /* CONFIG_MODULES_USE_ELF_RELA */ + /* Given an address, look for it in the module exception tables. */ const struct exception_table_entry *search_module_dbetables(unsigned long addr) { -- 2.12.1 ^ permalink raw reply related [flat|nested] 6+ messages in thread
* [PATCH 2/2] MIPS: module: Unify rel & rela reloc handling 2017-03-30 18:37 ` [PATCH 2/2] MIPS: module: Unify rel & rela reloc handling Paul Burton @ 2017-03-30 18:37 ` Paul Burton 0 siblings, 0 replies; 6+ messages in thread From: Paul Burton @ 2017-03-30 18:37 UTC (permalink / raw) To: linux-mips, Ralf Baechle; +Cc: Paul Burton The module load code has previously had entirely separate implementations for rel & rela style relocs, which unnecessarily duplicates a whole lot of code. Unify the implementations of both types of reloc, sharing the bulk of the code. Signed-off-by: Paul Burton <paul.burton@imgtec.com> Cc: linux-mips@linux-mips.org Cc: Ralf Baechle <ralf@linux-mips.org> --- arch/mips/include/asm/module.h | 8 +- arch/mips/kernel/Makefile | 1 - arch/mips/kernel/module-rela.c | 202 ----------------------------------------- arch/mips/kernel/module.c | 195 ++++++++++++++++++++++++++++++--------- 4 files changed, 154 insertions(+), 252 deletions(-) delete mode 100644 arch/mips/kernel/module-rela.c diff --git a/arch/mips/include/asm/module.h b/arch/mips/include/asm/module.h index 702c273e67a9..e51add184717 100644 --- a/arch/mips/include/asm/module.h +++ b/arch/mips/include/asm/module.h @@ -47,8 +47,8 @@ typedef struct { #define Elf_Mips_Rel Elf32_Rel #define Elf_Mips_Rela Elf32_Rela -#define ELF_MIPS_R_SYM(rel) ELF32_R_SYM(rel.r_info) -#define ELF_MIPS_R_TYPE(rel) ELF32_R_TYPE(rel.r_info) +#define ELF_MIPS_R_SYM(rel) ELF32_R_SYM((rel).r_info) +#define ELF_MIPS_R_TYPE(rel) ELF32_R_TYPE((rel).r_info) #endif @@ -65,8 +65,8 @@ typedef struct { #define Elf_Mips_Rel Elf64_Mips_Rel #define Elf_Mips_Rela Elf64_Mips_Rela -#define ELF_MIPS_R_SYM(rel) (rel.r_sym) -#define ELF_MIPS_R_TYPE(rel) (rel.r_type) +#define ELF_MIPS_R_SYM(rel) ((rel).r_sym) +#define ELF_MIPS_R_TYPE(rel) ((rel).r_type) #endif diff --git a/arch/mips/kernel/Makefile b/arch/mips/kernel/Makefile index 9a0e37b92ce0..f0edd7e8a0b7 100644 --- a/arch/mips/kernel/Makefile +++ b/arch/mips/kernel/Makefile @@ -31,7 +31,6 @@ obj-$(CONFIG_SYNC_R4K) += sync-r4k.o obj-$(CONFIG_DEBUG_FS) += segment.o obj-$(CONFIG_STACKTRACE) += stacktrace.o obj-$(CONFIG_MODULES) += module.o -obj-$(CONFIG_MODULES_USE_ELF_RELA) += module-rela.o obj-$(CONFIG_FTRACE_SYSCALLS) += ftrace.o obj-$(CONFIG_FUNCTION_TRACER) += mcount.o ftrace.o diff --git a/arch/mips/kernel/module-rela.c b/arch/mips/kernel/module-rela.c deleted file mode 100644 index 781168834456..000000000000 --- a/arch/mips/kernel/module-rela.c +++ /dev/null @@ -1,202 +0,0 @@ -/* - * This program is free software; you can redistribute it and/or modify - * it under the terms of the GNU General Public License as published by - * the Free Software Foundation; either version 2 of the License, or - * (at your option) any later version. - * - * This program is distributed in the hope that it will be useful, - * but WITHOUT ANY WARRANTY; without even the implied warranty of - * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the - * GNU General Public License for more details. - * - * You should have received a copy of the GNU General Public License - * along with this program; if not, write to the Free Software - * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA - * - * Copyright (C) 2001 Rusty Russell. - * Copyright (C) 2003, 2004 Ralf Baechle (ralf@linux-mips.org) - * Copyright (C) 2005 Thiemo Seufer - * Copyright (C) 2015 Imagination Technologies Ltd. - */ - -#include <linux/elf.h> -#include <linux/err.h> -#include <linux/errno.h> -#include <linux/moduleloader.h> - -extern int apply_r_mips_none(struct module *me, u32 *location, Elf_Addr v); - -static int apply_r_mips_32_rela(struct module *me, u32 *location, Elf_Addr v) -{ - *location = v; - - return 0; -} - -static int apply_r_mips_26_rela(struct module *me, u32 *location, Elf_Addr v) -{ - if (v % 4) { - pr_err("module %s: dangerous R_MIPS_26 RELA relocation\n", - me->name); - return -ENOEXEC; - } - - if ((v & 0xf0000000) != (((unsigned long)location + 4) & 0xf0000000)) { - pr_err("module %s: relocation overflow\n", me->name); - return -ENOEXEC; - } - - *location = (*location & ~0x03ffffff) | ((v >> 2) & 0x03ffffff); - - return 0; -} - -static int apply_r_mips_hi16_rela(struct module *me, u32 *location, Elf_Addr v) -{ - *location = (*location & 0xffff0000) | - ((((long long) v + 0x8000LL) >> 16) & 0xffff); - - return 0; -} - -static int apply_r_mips_lo16_rela(struct module *me, u32 *location, Elf_Addr v) -{ - *location = (*location & 0xffff0000) | (v & 0xffff); - - return 0; -} - -static int apply_r_mips_pc_rela(struct module *me, u32 *location, Elf_Addr v, - unsigned bits) -{ - unsigned long mask = GENMASK(bits - 1, 0); - unsigned long se_bits; - long offset; - - if (v % 4) { - pr_err("module %s: dangerous R_MIPS_PC%u RELA relocation\n", - me->name, bits); - return -ENOEXEC; - } - - offset = ((long)v - (long)location) >> 2; - - /* check the sign bit onwards are identical - ie. we didn't overflow */ - se_bits = (offset & BIT(bits - 1)) ? ~0ul : 0; - if ((offset & ~mask) != (se_bits & ~mask)) { - pr_err("module %s: relocation overflow\n", me->name); - return -ENOEXEC; - } - - *location = (*location & ~mask) | (offset & mask); - - return 0; -} - -static int apply_r_mips_pc16_rela(struct module *me, u32 *location, Elf_Addr v) -{ - return apply_r_mips_pc_rela(me, location, v, 16); -} - -static int apply_r_mips_pc21_rela(struct module *me, u32 *location, Elf_Addr v) -{ - return apply_r_mips_pc_rela(me, location, v, 21); -} - -static int apply_r_mips_pc26_rela(struct module *me, u32 *location, Elf_Addr v) -{ - return apply_r_mips_pc_rela(me, location, v, 26); -} - -static int apply_r_mips_64_rela(struct module *me, u32 *location, Elf_Addr v) -{ - *(Elf_Addr *)location = v; - - return 0; -} - -static int apply_r_mips_higher_rela(struct module *me, u32 *location, - Elf_Addr v) -{ - *location = (*location & 0xffff0000) | - ((((long long) v + 0x80008000LL) >> 32) & 0xffff); - - return 0; -} - -static int apply_r_mips_highest_rela(struct module *me, u32 *location, - Elf_Addr v) -{ - *location = (*location & 0xffff0000) | - ((((long long) v + 0x800080008000LL) >> 48) & 0xffff); - - return 0; -} - -static int (*reloc_handlers_rela[]) (struct module *me, u32 *location, - Elf_Addr v) = { - [R_MIPS_NONE] = apply_r_mips_none, - [R_MIPS_32] = apply_r_mips_32_rela, - [R_MIPS_26] = apply_r_mips_26_rela, - [R_MIPS_HI16] = apply_r_mips_hi16_rela, - [R_MIPS_LO16] = apply_r_mips_lo16_rela, - [R_MIPS_PC16] = apply_r_mips_pc16_rela, - [R_MIPS_64] = apply_r_mips_64_rela, - [R_MIPS_HIGHER] = apply_r_mips_higher_rela, - [R_MIPS_HIGHEST] = apply_r_mips_highest_rela, - [R_MIPS_PC21_S2] = apply_r_mips_pc21_rela, - [R_MIPS_PC26_S2] = apply_r_mips_pc26_rela, -}; - -int apply_relocate_add(Elf_Shdr *sechdrs, const char *strtab, - unsigned int symindex, unsigned int relsec, - struct module *me) -{ - Elf_Mips_Rela *rel = (void *) sechdrs[relsec].sh_addr; - int (*handler)(struct module *me, u32 *location, Elf_Addr v); - Elf_Sym *sym; - u32 *location; - unsigned int i, type; - Elf_Addr v; - int res; - - pr_debug("Applying relocate section %u to %u\n", relsec, - sechdrs[relsec].sh_info); - - for (i = 0; i < sechdrs[relsec].sh_size / sizeof(*rel); i++) { - /* This is where to make the change */ - location = (void *)sechdrs[sechdrs[relsec].sh_info].sh_addr - + rel[i].r_offset; - /* This is the symbol it is referring to */ - sym = (Elf_Sym *)sechdrs[symindex].sh_addr - + ELF_MIPS_R_SYM(rel[i]); - if (sym->st_value >= -MAX_ERRNO) { - /* Ignore unresolved weak symbol */ - if (ELF_ST_BIND(sym->st_info) == STB_WEAK) - continue; - pr_warn("%s: Unknown symbol %s\n", - me->name, strtab + sym->st_name); - return -ENOENT; - } - - type = ELF_MIPS_R_TYPE(rel[i]); - - if (type < ARRAY_SIZE(reloc_handlers_rela)) - handler = reloc_handlers_rela[type]; - else - handler = NULL; - - if (!handler) { - pr_err("%s: Unknown relocation type %u\n", - me->name, type); - return -EINVAL; - } - - v = sym->st_value + rel[i].r_addend; - res = handler(me, location, v); - if (res) - return res; - } - - return 0; -} diff --git a/arch/mips/kernel/module.c b/arch/mips/kernel/module.c index ddcfb59593b6..b250eb0c4fc1 100644 --- a/arch/mips/kernel/module.c +++ b/arch/mips/kernel/module.c @@ -53,22 +53,25 @@ void *module_alloc(unsigned long size) } #endif -int apply_r_mips_none(struct module *me, u32 *location, Elf_Addr v) +static int apply_r_mips_none(struct module *me, u32 *location, + u32 base, Elf_Addr v, bool rela) { return 0; } -static int apply_r_mips_32_rel(struct module *me, u32 *location, Elf_Addr v) +static int apply_r_mips_32(struct module *me, u32 *location, + u32 base, Elf_Addr v, bool rela) { - *location += v; + *location = base + v; return 0; } -static int apply_r_mips_26_rel(struct module *me, u32 *location, Elf_Addr v) +static int apply_r_mips_26(struct module *me, u32 *location, + u32 base, Elf_Addr v, bool rela) { if (v % 4) { - pr_err("module %s: dangerous R_MIPS_26 REL relocation\n", + pr_err("module %s: dangerous R_MIPS_26 relocation\n", me->name); return -ENOEXEC; } @@ -80,15 +83,22 @@ static int apply_r_mips_26_rel(struct module *me, u32 *location, Elf_Addr v) } *location = (*location & ~0x03ffffff) | - ((*location + (v >> 2)) & 0x03ffffff); + ((base + (v >> 2)) & 0x03ffffff); return 0; } -static int apply_r_mips_hi16_rel(struct module *me, u32 *location, Elf_Addr v) +static int apply_r_mips_hi16(struct module *me, u32 *location, + u32 base, Elf_Addr v, bool rela) { struct mips_hi16 *n; + if (rela) { + *location = (*location & 0xffff0000) | + ((((long long) v + 0x8000LL) >> 16) & 0xffff); + return 0; + } + /* * We cannot relocate this one now because we don't know the value of * the carry we need to add. Save the information, and let LO16 do the @@ -117,12 +127,18 @@ static void free_relocation_chain(struct mips_hi16 *l) } } -static int apply_r_mips_lo16_rel(struct module *me, u32 *location, Elf_Addr v) +static int apply_r_mips_lo16(struct module *me, u32 *location, + u32 base, Elf_Addr v, bool rela) { - unsigned long insnlo = *location; + unsigned long insnlo = base; struct mips_hi16 *l; Elf_Addr val, vallo; + if (rela) { + *location = (*location & 0xffff0000) | (v & 0xffff); + return 0; + } + /* Sign extend the addend we extract from the lo insn. */ vallo = ((insnlo & 0xffff) ^ 0x8000) - 0x8000; @@ -178,26 +194,26 @@ static int apply_r_mips_lo16_rel(struct module *me, u32 *location, Elf_Addr v) free_relocation_chain(l); me->arch.r_mips_hi16_list = NULL; - pr_err("module %s: dangerous R_MIPS_LO16 REL relocation\n", me->name); + pr_err("module %s: dangerous R_MIPS_LO16 relocation\n", me->name); return -ENOEXEC; } -static int apply_r_mips_pc_rel(struct module *me, u32 *location, Elf_Addr v, - unsigned bits) +static int apply_r_mips_pc(struct module *me, u32 *location, u32 base, + Elf_Addr v, unsigned int bits) { unsigned long mask = GENMASK(bits - 1, 0); unsigned long se_bits; long offset; if (v % 4) { - pr_err("module %s: dangerous R_MIPS_PC%u REL relocation\n", + pr_err("module %s: dangerous R_MIPS_PC%u relocation\n", me->name, bits); return -ENOEXEC; } - /* retrieve & sign extend implicit addend */ - offset = *location & mask; + /* retrieve & sign extend implicit addend if any */ + offset = base & mask; offset |= (offset & BIT(bits - 1)) ? ~mask : 0; offset += ((long)v - (long)location) >> 2; @@ -214,56 +230,121 @@ static int apply_r_mips_pc_rel(struct module *me, u32 *location, Elf_Addr v, return 0; } -static int apply_r_mips_pc16_rel(struct module *me, u32 *location, Elf_Addr v) +static int apply_r_mips_pc16(struct module *me, u32 *location, + u32 base, Elf_Addr v, bool rela) { - return apply_r_mips_pc_rel(me, location, v, 16); + return apply_r_mips_pc(me, location, base, v, 16); } -static int apply_r_mips_pc21_rel(struct module *me, u32 *location, Elf_Addr v) +static int apply_r_mips_pc21(struct module *me, u32 *location, + u32 base, Elf_Addr v, bool rela) { - return apply_r_mips_pc_rel(me, location, v, 21); + return apply_r_mips_pc(me, location, base, v, 21); } -static int apply_r_mips_pc26_rel(struct module *me, u32 *location, Elf_Addr v) +static int apply_r_mips_pc26(struct module *me, u32 *location, + u32 base, Elf_Addr v, bool rela) { - return apply_r_mips_pc_rel(me, location, v, 26); + return apply_r_mips_pc(me, location, base, v, 26); } -static int (*reloc_handlers_rel[]) (struct module *me, u32 *location, - Elf_Addr v) = { +static int apply_r_mips_64(struct module *me, u32 *location, + u32 base, Elf_Addr v, bool rela) +{ + if (WARN_ON(!rela)) + return -EINVAL; + + *(Elf_Addr *)location = v; + + return 0; +} + +static int apply_r_mips_higher(struct module *me, u32 *location, + u32 base, Elf_Addr v, bool rela) +{ + if (WARN_ON(!rela)) + return -EINVAL; + + *location = (*location & 0xffff0000) | + ((((long long)v + 0x80008000LL) >> 32) & 0xffff); + + return 0; +} + +static int apply_r_mips_highest(struct module *me, u32 *location, + u32 base, Elf_Addr v, bool rela) +{ + if (WARN_ON(!rela)) + return -EINVAL; + + *location = (*location & 0xffff0000) | + ((((long long)v + 0x800080008000LL) >> 48) & 0xffff); + + return 0; +} + +/** + * reloc_handler() - Apply a particular relocation to a module + * @me: the module to apply the reloc to + * @location: the address at which the reloc is to be applied + * @base: the existing value at location for REL-style; 0 for RELA-style + * @v: the value of the reloc, with addend for RELA-style + * + * Each implemented reloc_handler function applies a particular type of + * relocation to the module @me. Relocs that may be found in either REL or RELA + * variants can be handled by making use of the @base & @v parameters which are + * set to values which abstract the difference away from the particular reloc + * implementations. + * + * Return: 0 upon success, else -ERRNO + */ +typedef int (*reloc_handler)(struct module *me, u32 *location, + u32 base, Elf_Addr v, bool rela); + +/* The handlers for known reloc types */ +static reloc_handler reloc_handlers[] = { [R_MIPS_NONE] = apply_r_mips_none, - [R_MIPS_32] = apply_r_mips_32_rel, - [R_MIPS_26] = apply_r_mips_26_rel, - [R_MIPS_HI16] = apply_r_mips_hi16_rel, - [R_MIPS_LO16] = apply_r_mips_lo16_rel, - [R_MIPS_PC16] = apply_r_mips_pc16_rel, - [R_MIPS_PC21_S2] = apply_r_mips_pc21_rel, - [R_MIPS_PC26_S2] = apply_r_mips_pc26_rel, + [R_MIPS_32] = apply_r_mips_32, + [R_MIPS_26] = apply_r_mips_26, + [R_MIPS_HI16] = apply_r_mips_hi16, + [R_MIPS_LO16] = apply_r_mips_lo16, + [R_MIPS_PC16] = apply_r_mips_pc16, + [R_MIPS_64] = apply_r_mips_64, + [R_MIPS_HIGHER] = apply_r_mips_higher, + [R_MIPS_HIGHEST] = apply_r_mips_highest, + [R_MIPS_PC21_S2] = apply_r_mips_pc21, + [R_MIPS_PC26_S2] = apply_r_mips_pc26, }; -int apply_relocate(Elf_Shdr *sechdrs, const char *strtab, - unsigned int symindex, unsigned int relsec, - struct module *me) +static int __apply_relocate(Elf_Shdr *sechdrs, const char *strtab, + unsigned int symindex, unsigned int relsec, + struct module *me, bool rela) { - Elf_Mips_Rel *rel = (void *) sechdrs[relsec].sh_addr; - int (*handler)(struct module *me, u32 *location, Elf_Addr v); + union { + Elf_Mips_Rel *rel; + Elf_Mips_Rela *rela; + } r; + reloc_handler handler; Elf_Sym *sym; - u32 *location; + u32 *location, base; unsigned int i, type; Elf_Addr v; int err = 0; + size_t reloc_sz; pr_debug("Applying relocate section %u to %u\n", relsec, sechdrs[relsec].sh_info); + r.rel = (void *)sechdrs[relsec].sh_addr; + reloc_sz = rela ? sizeof(*r.rela) : sizeof(*r.rel); me->arch.r_mips_hi16_list = NULL; - for (i = 0; i < sechdrs[relsec].sh_size / sizeof(*rel); i++) { + for (i = 0; i < sechdrs[relsec].sh_size / reloc_sz; i++) { /* This is where to make the change */ location = (void *)sechdrs[sechdrs[relsec].sh_info].sh_addr - + rel[i].r_offset; + + r.rel->r_offset; /* This is the symbol it is referring to */ sym = (Elf_Sym *)sechdrs[symindex].sh_addr - + ELF_MIPS_R_SYM(rel[i]); + + ELF_MIPS_R_SYM(*r.rel); if (sym->st_value >= -MAX_ERRNO) { /* Ignore unresolved weak symbol */ if (ELF_ST_BIND(sym->st_info) == STB_WEAK) @@ -274,10 +355,9 @@ int apply_relocate(Elf_Shdr *sechdrs, const char *strtab, goto out; } - type = ELF_MIPS_R_TYPE(rel[i]); - - if (type < ARRAY_SIZE(reloc_handlers_rel)) - handler = reloc_handlers_rel[type]; + type = ELF_MIPS_R_TYPE(*r.rel); + if (type < ARRAY_SIZE(reloc_handlers)) + handler = reloc_handlers[type]; else handler = NULL; @@ -288,8 +368,17 @@ int apply_relocate(Elf_Shdr *sechdrs, const char *strtab, goto out; } - v = sym->st_value; - err = handler(me, location, v); + if (rela) { + v = sym->st_value + r.rela->r_addend; + base = 0; + r.rela = &r.rela[1]; + } else { + v = sym->st_value; + base = *location; + r.rel = &r.rel[1]; + } + + err = handler(me, location, base, v, rela); if (err) goto out; } @@ -312,6 +401,22 @@ int apply_relocate(Elf_Shdr *sechdrs, const char *strtab, return err; } +int apply_relocate(Elf_Shdr *sechdrs, const char *strtab, + unsigned int symindex, unsigned int relsec, + struct module *me) +{ + return __apply_relocate(sechdrs, strtab, symindex, relsec, me, false); +} + +#ifdef CONFIG_MODULES_USE_ELF_RELA +int apply_relocate_add(Elf_Shdr *sechdrs, const char *strtab, + unsigned int symindex, unsigned int relsec, + struct module *me) +{ + return __apply_relocate(sechdrs, strtab, symindex, relsec, me, true); +} +#endif /* CONFIG_MODULES_USE_ELF_RELA */ + /* Given an address, look for it in the module exception tables. */ const struct exception_table_entry *search_module_dbetables(unsigned long addr) { -- 2.12.1 ^ permalink raw reply related [flat|nested] 6+ messages in thread
end of thread, other threads:[~2017-03-30 18:39 UTC | newest] Thread overview: 6+ messages (download: mbox.gz / follow: Atom feed) -- links below jump to the message on this page -- 2017-03-30 18:37 [PATCH 0/2] MIPS: module: Fixup error path & refactor Paul Burton 2017-03-30 18:37 ` Paul Burton 2017-03-30 18:37 ` [PATCH 1/2] MIPS: module: Ensure we always clean up r_mips_hi16_list Paul Burton 2017-03-30 18:37 ` Paul Burton 2017-03-30 18:37 ` [PATCH 2/2] MIPS: module: Unify rel & rela reloc handling Paul Burton 2017-03-30 18:37 ` Paul Burton
This is a public inbox, see mirroring instructions for how to clone and mirror all data and code used for this inbox; as well as URLs for NNTP newsgroup(s).