From:Suzuki K. Poulose <[email protected]> Move the common code, shared by both native and compat ELF core generation code to a single instance.These functions could be re-used later for application core dump infrastructure.
Signed-off-by: Suzuki K. Poulose <[email protected]> --- fs/Makefile | 1 fs/binfmt_elf.c | 156 ------------------------------------- fs/elfcore-common.c | 161 ++++++++++++++++++++++++++++++++++++++ include/linux/elfcore-internal.h | 46 +++++++++++ 4 files changed, 209 insertions(+), 155 deletions(-) create mode 100644 fs/elfcore-common.c create mode 100644 include/linux/elfcore-internal.h diff --git a/fs/Makefile b/fs/Makefile index 4fe6df3..70e7add 100644 --- a/fs/Makefile +++ b/fs/Makefile @@ -37,6 +37,7 @@ obj-$(CONFIG_BINFMT_MISC) += binfmt_misc.o obj-$(CONFIG_BINFMT_SCRIPT) += binfmt_script.o obj-$(CONFIG_BINFMT_ELF) += binfmt_elf.o obj-$(CONFIG_COMPAT_BINFMT_ELF) += compat_binfmt_elf.o +obj-$(CONFIG_ELF_CORE) += elfcore-common.o obj-$(CONFIG_BINFMT_ELF_FDPIC) += binfmt_elf_fdpic.o obj-$(CONFIG_BINFMT_SOM) += binfmt_som.o obj-$(CONFIG_BINFMT_FLAT) += binfmt_flat.o diff --git a/fs/binfmt_elf.c b/fs/binfmt_elf.c index 100edcc..6c8df47 100644 --- a/fs/binfmt_elf.c +++ b/fs/binfmt_elf.c @@ -37,7 +37,7 @@ #include <asm/uaccess.h> #include <asm/param.h> #include <asm/page.h> - +#include <linux/elfcore-internal.h> #ifndef user_long_t #define user_long_t long #endif @@ -1095,124 +1095,6 @@ out: * Jeremy Fitzhardinge <[email protected]> */ -/* - * The purpose of always_dump_vma() is to make sure that special kernel mappings - * that are useful for post-mortem analysis are included in every core dump. - * In that way we ensure that the core dump is fully interpretable later - * without matching up the same kernel and hardware config to see what PC values - * meant. These special mappings include - vDSO, vsyscall, and other - * architecture specific mappings - */ -static bool always_dump_vma(struct vm_area_struct *vma) -{ - /* Any vsyscall mappings? */ - if (vma == get_gate_vma(vma->vm_mm)) - return true; - /* - * arch_vma_name() returns non-NULL for special architecture mappings, - * such as vDSO sections. - */ - if (arch_vma_name(vma)) - return true; - - return false; -} - -/* - * Decide what to dump of a segment, part, all or none. - */ -static unsigned long vma_dump_size(struct vm_area_struct *vma, - unsigned long mm_flags) -{ -#define FILTER(type) (mm_flags & (1UL << MMF_DUMP_##type)) - - /* always dump the vdso and vsyscall sections */ - if (always_dump_vma(vma)) - goto whole; - - if (vma->vm_flags & VM_DONTDUMP) - return 0; - - /* Hugetlb memory check */ - if (vma->vm_flags & VM_HUGETLB) { - if ((vma->vm_flags & VM_SHARED) && FILTER(HUGETLB_SHARED)) - goto whole; - if (!(vma->vm_flags & VM_SHARED) && FILTER(HUGETLB_PRIVATE)) - goto whole; - return 0; - } - - /* Do not dump I/O mapped devices or special mappings */ - if (vma->vm_flags & VM_IO) - return 0; - - /* By default, dump shared memory if mapped from an anonymous file. */ - if (vma->vm_flags & VM_SHARED) { - if (file_inode(vma->vm_file)->i_nlink == 0 ? - FILTER(ANON_SHARED) : FILTER(MAPPED_SHARED)) - goto whole; - return 0; - } - - /* Dump segments that have been written to. */ - if (vma->anon_vma && FILTER(ANON_PRIVATE)) - goto whole; - if (vma->vm_file == NULL) - return 0; - - if (FILTER(MAPPED_PRIVATE)) - goto whole; - - /* - * If this looks like the beginning of a DSO or executable mapping, - * check for an ELF header. If we find one, dump the first page to - * aid in determining what was mapped here. - */ - if (FILTER(ELF_HEADERS) && - vma->vm_pgoff == 0 && (vma->vm_flags & VM_READ)) { - u32 __user *header = (u32 __user *) vma->vm_start; - u32 word; - mm_segment_t fs = get_fs(); - /* - * Doing it this way gets the constant folded by GCC. - */ - union { - u32 cmp; - char elfmag[SELFMAG]; - } magic; - BUILD_BUG_ON(SELFMAG != sizeof word); - magic.elfmag[EI_MAG0] = ELFMAG0; - magic.elfmag[EI_MAG1] = ELFMAG1; - magic.elfmag[EI_MAG2] = ELFMAG2; - magic.elfmag[EI_MAG3] = ELFMAG3; - /* - * Switch to the user "segment" for get_user(), - * then put back what elf_core_dump() had in place. - */ - set_fs(USER_DS); - if (unlikely(get_user(word, header))) - word = 0; - set_fs(fs); - if (word == magic.cmp) - return PAGE_SIZE; - } - -#undef FILTER - - return 0; - -whole: - return vma->vm_end - vma->vm_start; -} - -/* An ELF note in memory */ -struct memelfnote -{ - const char *name; - int type; - unsigned int datasz; - void *data; -}; static int notesize(struct memelfnote *en) { @@ -1291,16 +1173,6 @@ static void fill_elf_note_phdr(struct elf_phdr *phdr, int sz, loff_t offset) return; } -static void fill_note(struct memelfnote *note, const char *name, int type, - unsigned int sz, void *data) -{ - note->name = name; - note->type = type; - note->datasz = sz; - note->data = data; - return; -} - /* * fill up all the fields in prstatus from the given task struct, except * registers which need to be filled up separately. @@ -1974,32 +1846,6 @@ static void free_note_info(struct elf_note_info *info) #endif -static struct vm_area_struct *first_vma(struct task_struct *tsk, - struct vm_area_struct *gate_vma) -{ - struct vm_area_struct *ret = tsk->mm->mmap; - - if (ret) - return ret; - return gate_vma; -} -/* - * Helper function for iterating across a vma list. It ensures that the caller - * will visit `gate_vma' prior to terminating the search. - */ -static struct vm_area_struct *next_vma(struct vm_area_struct *this_vma, - struct vm_area_struct *gate_vma) -{ - struct vm_area_struct *ret; - - ret = this_vma->vm_next; - if (ret) - return ret; - if (this_vma == gate_vma) - return NULL; - return gate_vma; -} - static void fill_extnum_info(struct elfhdr *elf, struct elf_shdr *shdr4extnum, elf_addr_t e_shoff, int segs) { diff --git a/fs/elfcore-common.c b/fs/elfcore-common.c new file mode 100644 index 0000000..4886f15 --- /dev/null +++ b/fs/elfcore-common.c @@ -0,0 +1,161 @@ +/* + * + * Copyright 1993, 1994: Eric Youngdale ([email protected]). + * + * Initial write up for ELF_CORE : + * Modelled on fs/exec.c:aout_core_dump() + * Jeremy Fitzhardinge <[email protected]> + * + * Moved common routines used by both native and compat ELF core generation + * from binfmt_elf.c to a single instance. + * Suzuki K. Poulose <[email protected]> + */ + +#include <linux/mm.h> +#include <linux/mman.h> +#include <linux/sched.h> +#include <linux/fs.h> +#include <linux/elf.h> +#include <asm/uaccess.h> +#include <asm/param.h> +#include <asm/page.h> +#include <linux/elfcore-internal.h> + +static struct vm_area_struct *first_vma(struct task_struct *tsk, + struct vm_area_struct *gate_vma) +{ + struct vm_area_struct *ret = tsk->mm->mmap; + + if (ret) + return ret; + return gate_vma; +} + +/* + * Helper function for iterating across a vma list. It ensures that the caller + * will visit `gate_vma' prior to terminating the search. + */ +static struct vm_area_struct *next_vma(struct vm_area_struct *this_vma, + struct vm_area_struct *gate_vma) +{ + struct vm_area_struct *ret; + + ret = this_vma->vm_next; + if (ret) + return ret; + if (this_vma == gate_vma) + return NULL; + return gate_vma; +} + +/* + * The purpose of always_dump_vma() is to make sure that special kernel mappings + * that are useful for post-mortem analysis are included in every core dump. + * In that way we ensure that the core dump is fully interpretable later + * without matching up the same kernel and hardware config to see what PC values + * meant. These special mappings include - vDSO, vsyscall, and other + * architecture specific mappings + */ +static bool always_dump_vma(struct vm_area_struct *vma) +{ + /* Any vsyscall mappings? */ + if (vma == get_gate_vma(vma->vm_mm)) + return true; + /* + * arch_vma_name() returns non-NULL for special architecture mappings, + * such as vDSO sections. + */ + if (arch_vma_name(vma)) + return true; + + return false; +} + +/* + * Decide what to dump of a segment, part, all or none. + */ +static unsigned long vma_dump_size(struct vm_area_struct *vma, + unsigned long mm_flags) +{ +#define FILTER(type) (mm_flags & (1UL << MMF_DUMP_##type)) + + /* always dump the vdso and vsyscall sections */ + if (always_dump_vma(vma)) + goto whole; + + if (vma->vm_flags & VM_DONTDUMP) + return 0; + + /* Hugetlb memory check */ + if (vma->vm_flags & VM_HUGETLB) { + if ((vma->vm_flags & VM_SHARED) && FILTER(HUGETLB_SHARED)) + goto whole; + if (!(vma->vm_flags & VM_SHARED) && FILTER(HUGETLB_PRIVATE)) + goto whole; + return 0; + } + + /* Do not dump I/O mapped devices or special mappings */ + if (vma->vm_flags & VM_IO) + return 0; + + /* By default, dump shared memory if mapped from an anonymous file. */ + if (vma->vm_flags & VM_SHARED) { + if (file_inode(vma->vm_file)->i_nlink == 0 ? + FILTER(ANON_SHARED) : FILTER(MAPPED_SHARED)) + goto whole; + return 0; + } + + /* Dump segments that have been written to. */ + if (vma->anon_vma && FILTER(ANON_PRIVATE)) + goto whole; + if (vma->vm_file == NULL) + return 0; + + if (FILTER(MAPPED_PRIVATE)) + goto whole; + + /* + * If this looks like the beginning of a DSO or executable mapping, + * check for an ELF header. If we find one, dump the first page to + * aid in determining what was mapped here. + */ + if (FILTER(ELF_HEADERS) && + vma->vm_pgoff == 0 && (vma->vm_flags & VM_READ)) { + u32 __user *header = (u32 __user *) vma->vm_start; + + u32 word; + mm_segment_t fs = get_fs(); + /* + * Doing it this way gets the constant folded by GCC. + */ + union { + u32 cmp; + char elfmag[SELFMAG]; + } magic; + BUILD_BUG_ON(SELFMAG != sizeof word); + magic.elfmag[EI_MAG0] = ELFMAG0; + magic.elfmag[EI_MAG1] = ELFMAG1; + magic.elfmag[EI_MAG2] = ELFMAG2; + magic.elfmag[EI_MAG3] = ELFMAG3; + /* + * Switch to the user "segment" for get_user(), + * then put back what elf_core_dump() had in place. + */ + set_fs(USER_DS); + if (unlikely(get_user(word, header))) + word = 0; + set_fs(fs); + if (word == magic.cmp) + return PAGE_SIZE; + } + +#undef FILTER + + return 0; + +whole: + return vma->vm_end - vma->vm_start; +} + diff --git a/include/linux/elfcore-internal.h b/include/linux/elfcore-internal.h new file mode 100644 index 0000000..f6354f0 --- /dev/null +++ b/include/linux/elfcore-internal.h @@ -0,0 +1,46 @@ +/* + * Common routines for native and compat elf core generation. + * + * Copyright 1993, 1994: Eric Youngdale ([email protected]). + * + * Modelled on fs/exec.c:aout_core_dump() + * Jeremy Fitzhardinge <[email protected]> + * + * Moved the common routines from binfmt_elf.c to elfcore-common.c + * - Suzuki K. Poulose <[email protected]> + */ + +#ifndef __ELF_CORE_INTERNAL_H +#define __ELF_CORE_INTERNAL_H + +#ifdef __KERNEL__ + +/* An ELF note in memory */ +struct memelfnote +{ + const char *name; + int type; + unsigned int datasz; + void *data; +}; + +static void fill_note(struct memelfnote *note, const char *name, int type, + unsigned int sz, void *data) +{ + note->name = name; + note->type = type; + note->datasz = sz; + note->data = data; + return; +} + +extern struct vm_area_struct *first_vma(struct task_struct *tsk, + struct vm_area_struct *gate_vma); +extern struct vm_area_struct *next_vma(struct vm_area_struct *this_vma, + struct vm_area_struct *gate_vma); +extern unsigned long vma_dump_size(struct vm_area_struct *vma, + unsigned long mm_flags); + +#endif +#endif + -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
