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Diffstat (limited to 'fs/binfmt_elf_fdpic.c')
-rw-r--r--fs/binfmt_elf_fdpic.c181
1 files changed, 112 insertions, 69 deletions
diff --git a/fs/binfmt_elf_fdpic.c b/fs/binfmt_elf_fdpic.c
index 18d77297ccc8..6d6a16c5e9bb 100644
--- a/fs/binfmt_elf_fdpic.c
+++ b/fs/binfmt_elf_fdpic.c
@@ -34,6 +34,7 @@
#include <linux/elf.h>
#include <linux/elf-fdpic.h>
#include <linux/elfcore.h>
+#include <linux/coredump.h>
#include <asm/uaccess.h>
#include <asm/param.h>
@@ -1216,26 +1217,6 @@ static int elf_fdpic_map_file_by_direct_mmap(struct elf_fdpic_params *params,
#ifdef CONFIG_ELF_CORE
/*
- * These are the only things you should do on a core-file: use only these
- * functions to write out all the necessary info.
- */
-static int dump_write(struct file *file, const void *addr, int nr)
-{
- return file->f_op->write(file, addr, nr, &file->f_pos) == nr;
-}
-
-static int dump_seek(struct file *file, loff_t off)
-{
- if (file->f_op->llseek) {
- if (file->f_op->llseek(file, off, SEEK_SET) != off)
- return 0;
- } else {
- file->f_pos = off;
- }
- return 1;
-}
-
-/*
* Decide whether a segment is worth dumping; default is yes to be
* sure (missing info is worse than too much; etc).
* Personally I'd include everything, and use the coredump limit...
@@ -1313,35 +1294,35 @@ static int notesize(struct memelfnote *en)
/* #define DEBUG */
-#define DUMP_WRITE(addr, nr) \
- do { if (!dump_write(file, (addr), (nr))) return 0; } while(0)
-#define DUMP_SEEK(off) \
- do { if (!dump_seek(file, (off))) return 0; } while(0)
+#define DUMP_WRITE(addr, nr, foffset) \
+ do { if (!dump_write(file, (addr), (nr))) return 0; *foffset += (nr); } while(0)
-static int writenote(struct memelfnote *men, struct file *file)
+static int alignfile(struct file *file, loff_t *foffset)
{
- struct elf_note en;
+ static const char buf[4] = { 0, };
+ DUMP_WRITE(buf, roundup(*foffset, 4) - *foffset, foffset);
+ return 1;
+}
+static int writenote(struct memelfnote *men, struct file *file,
+ loff_t *foffset)
+{
+ struct elf_note en;
en.n_namesz = strlen(men->name) + 1;
en.n_descsz = men->datasz;
en.n_type = men->type;
- DUMP_WRITE(&en, sizeof(en));
- DUMP_WRITE(men->name, en.n_namesz);
- /* XXX - cast from long long to long to avoid need for libgcc.a */
- DUMP_SEEK(roundup((unsigned long)file->f_pos, 4)); /* XXX */
- DUMP_WRITE(men->data, men->datasz);
- DUMP_SEEK(roundup((unsigned long)file->f_pos, 4)); /* XXX */
+ DUMP_WRITE(&en, sizeof(en), foffset);
+ DUMP_WRITE(men->name, en.n_namesz, foffset);
+ if (!alignfile(file, foffset))
+ return 0;
+ DUMP_WRITE(men->data, men->datasz, foffset);
+ if (!alignfile(file, foffset))
+ return 0;
return 1;
}
#undef DUMP_WRITE
-#undef DUMP_SEEK
-
-#define DUMP_WRITE(addr, nr) \
- if ((size += (nr)) > cprm->limit || \
- !dump_write(cprm->file, (addr), (nr))) \
- goto end_coredump;
static inline void fill_elf_fdpic_header(struct elfhdr *elf, int segs)
{
@@ -1524,6 +1505,22 @@ static int elf_dump_thread_status(long signr, struct elf_thread_status *t)
return sz;
}
+static void fill_extnum_info(struct elfhdr *elf, struct elf_shdr *shdr4extnum,
+ elf_addr_t e_shoff, int segs)
+{
+ elf->e_shoff = e_shoff;
+ elf->e_shentsize = sizeof(*shdr4extnum);
+ elf->e_shnum = 1;
+ elf->e_shstrndx = SHN_UNDEF;
+
+ memset(shdr4extnum, 0, sizeof(*shdr4extnum));
+
+ shdr4extnum->sh_type = SHT_NULL;
+ shdr4extnum->sh_size = elf->e_shnum;
+ shdr4extnum->sh_link = elf->e_shstrndx;
+ shdr4extnum->sh_info = segs;
+}
+
/*
* dump the segments for an MMU process
*/
@@ -1552,7 +1549,7 @@ static int elf_fdpic_dump_segments(struct file *file, size_t *size,
err = -EIO;
kunmap(page);
page_cache_release(page);
- } else if (!dump_seek(file, file->f_pos + PAGE_SIZE))
+ } else if (!dump_seek(file, PAGE_SIZE))
err = -EFBIG;
if (err)
goto out;
@@ -1588,6 +1585,17 @@ static int elf_fdpic_dump_segments(struct file *file, size_t *size,
}
#endif
+static size_t elf_core_vma_data_size(unsigned long mm_flags)
+{
+ struct vm_area_struct *vma;
+ size_t size = 0;
+
+ for (vma = current->mm->mmap; vma; vma->vm_next)
+ if (maydump(vma, mm_flags))
+ size += vma->vm_end - vma->vm_start;
+ return size;
+}
+
/*
* Actual dumper
*
@@ -1605,7 +1613,7 @@ static int elf_fdpic_core_dump(struct coredump_params *cprm)
int i;
struct vm_area_struct *vma;
struct elfhdr *elf = NULL;
- loff_t offset = 0, dataoff;
+ loff_t offset = 0, dataoff, foffset;
int numnote;
struct memelfnote *notes = NULL;
struct elf_prstatus *prstatus = NULL; /* NT_PRSTATUS */
@@ -1618,7 +1626,10 @@ static int elf_fdpic_core_dump(struct coredump_params *cprm)
#endif
int thread_status_size = 0;
elf_addr_t *auxv;
- unsigned long mm_flags;
+ struct elf_phdr *phdr4note = NULL;
+ struct elf_shdr *shdr4extnum = NULL;
+ Elf_Half e_phnum;
+ elf_addr_t e_shoff;
/*
* We no longer stop all VM operations.
@@ -1683,12 +1694,18 @@ static int elf_fdpic_core_dump(struct coredump_params *cprm)
elf_core_copy_regs(&prstatus->pr_reg, cprm->regs);
segs = current->mm->map_count;
-#ifdef ELF_CORE_EXTRA_PHDRS
- segs += ELF_CORE_EXTRA_PHDRS;
-#endif
+ segs += elf_core_extra_phdrs();
+
+ /* for notes section */
+ segs++;
+
+ /* If segs > PN_XNUM(0xffff), then e_phnum overflows. To avoid
+ * this, kernel supports extended numbering. Have a look at
+ * include/linux/elf.h for further information. */
+ e_phnum = segs > PN_XNUM ? PN_XNUM : segs;
/* Set up header */
- fill_elf_fdpic_header(elf, segs + 1); /* including notes section */
+ fill_elf_fdpic_header(elf, e_phnum);
has_dumped = 1;
current->flags |= PF_DUMPCORE;
@@ -1727,13 +1744,12 @@ static int elf_fdpic_core_dump(struct coredump_params *cprm)
fs = get_fs();
set_fs(KERNEL_DS);
- DUMP_WRITE(elf, sizeof(*elf));
offset += sizeof(*elf); /* Elf header */
- offset += (segs+1) * sizeof(struct elf_phdr); /* Program headers */
+ offset += segs * sizeof(struct elf_phdr); /* Program headers */
+ foffset = offset;
/* Write notes phdr entry */
{
- struct elf_phdr phdr;
int sz = 0;
for (i = 0; i < numnote; i++)
@@ -1741,20 +1757,38 @@ static int elf_fdpic_core_dump(struct coredump_params *cprm)
sz += thread_status_size;
- fill_elf_note_phdr(&phdr, sz, offset);
+ phdr4note = kmalloc(sizeof(*phdr4note), GFP_KERNEL);
+ if (!phdr4note)
+ goto end_coredump;
+
+ fill_elf_note_phdr(phdr4note, sz, offset);
offset += sz;
- DUMP_WRITE(&phdr, sizeof(phdr));
}
/* Page-align dumped data */
dataoff = offset = roundup(offset, ELF_EXEC_PAGESIZE);
- /*
- * We must use the same mm->flags while dumping core to avoid
- * inconsistency between the program headers and bodies, otherwise an
- * unusable core file can be generated.
- */
- mm_flags = current->mm->flags;
+ offset += elf_core_vma_data_size(cprm->mm_flags);
+ offset += elf_core_extra_data_size();
+ e_shoff = offset;
+
+ if (e_phnum == PN_XNUM) {
+ shdr4extnum = kmalloc(sizeof(*shdr4extnum), GFP_KERNEL);
+ if (!shdr4extnum)
+ goto end_coredump;
+ fill_extnum_info(elf, shdr4extnum, e_shoff, segs);
+ }
+
+ offset = dataoff;
+
+ size += sizeof(*elf);
+ if (size > cprm->limit || !dump_write(cprm->file, elf, sizeof(*elf)))
+ goto end_coredump;
+
+ size += sizeof(*phdr4note);
+ if (size > cprm->limit
+ || !dump_write(cprm->file, phdr4note, sizeof(*phdr4note)))
+ goto end_coredump;
/* write program headers for segments dump */
for (vma = current->mm->mmap; vma; vma = vma->vm_next) {
@@ -1767,7 +1801,7 @@ static int elf_fdpic_core_dump(struct coredump_params *cprm)
phdr.p_offset = offset;
phdr.p_vaddr = vma->vm_start;
phdr.p_paddr = 0;
- phdr.p_filesz = maydump(vma, mm_flags) ? sz : 0;
+ phdr.p_filesz = maydump(vma, cprm->mm_flags) ? sz : 0;
phdr.p_memsz = sz;
offset += phdr.p_filesz;
phdr.p_flags = vma->vm_flags & VM_READ ? PF_R : 0;
@@ -1777,16 +1811,18 @@ static int elf_fdpic_core_dump(struct coredump_params *cprm)
phdr.p_flags |= PF_X;
phdr.p_align = ELF_EXEC_PAGESIZE;
- DUMP_WRITE(&phdr, sizeof(phdr));
+ size += sizeof(phdr);
+ if (size > cprm->limit
+ || !dump_write(cprm->file, &phdr, sizeof(phdr)))
+ goto end_coredump;
}
-#ifdef ELF_CORE_WRITE_EXTRA_PHDRS
- ELF_CORE_WRITE_EXTRA_PHDRS;
-#endif
+ if (!elf_core_write_extra_phdrs(cprm->file, offset, &size, cprm->limit))
+ goto end_coredump;
/* write out the notes section */
for (i = 0; i < numnote; i++)
- if (!writenote(notes + i, cprm->file))
+ if (!writenote(notes + i, cprm->file, &foffset))
goto end_coredump;
/* write out the thread status notes section */
@@ -1795,20 +1831,27 @@ static int elf_fdpic_core_dump(struct coredump_params *cprm)
list_entry(t, struct elf_thread_status, list);
for (i = 0; i < tmp->num_notes; i++)
- if (!writenote(&tmp->notes[i], cprm->file))
+ if (!writenote(&tmp->notes[i], cprm->file, &foffset))
goto end_coredump;
}
- if (!dump_seek(cprm->file, dataoff))
+ if (!dump_seek(cprm->file, dataoff - foffset))
goto end_coredump;
if (elf_fdpic_dump_segments(cprm->file, &size, &cprm->limit,
- mm_flags) < 0)
+ cprm->mm_flags) < 0)
goto end_coredump;
-#ifdef ELF_CORE_WRITE_EXTRA_DATA
- ELF_CORE_WRITE_EXTRA_DATA;
-#endif
+ if (!elf_core_write_extra_data(cprm->file, &size, cprm->limit))
+ goto end_coredump;
+
+ if (e_phnum == PN_XNUM) {
+ size += sizeof(*shdr4extnum);
+ if (size > cprm->limit
+ || !dump_write(cprm->file, shdr4extnum,
+ sizeof(*shdr4extnum)))
+ goto end_coredump;
+ }
if (cprm->file->f_pos != offset) {
/* Sanity check */
@@ -1826,7 +1869,7 @@ cleanup:
list_del(tmp);
kfree(list_entry(tmp, struct elf_thread_status, list));
}
-
+ kfree(phdr4note);
kfree(elf);
kfree(prstatus);
kfree(psinfo);