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authorOlof Johansson <olof@lixom.net>2013-07-12 19:59:39 +0200
committerOlof Johansson <olof@lixom.net>2013-07-12 19:59:39 +0200
commitf4b96f5e4ff8d86699c851c10245e102809b0331 (patch)
treef766102263bed71738431cabb4d4f6f086005cd8 /fs/proc/vmcore.c
parentARM: omap2: add select of TI_PRIV_EDMA (diff)
parentARM: OMAP2+: omap2plus_defconfig: Enable appended DTB support (diff)
downloadlinux-f4b96f5e4ff8d86699c851c10245e102809b0331.tar.xz
linux-f4b96f5e4ff8d86699c851c10245e102809b0331.zip
Merge tag 'omap-for-v3.11/fixes-for-merge-window' of git://git.kernel.org/pub/scm/linux/kernel/git/tmlind/linux-omap into fixes
Omap fixes and minor defconfig updates that would be good to get in before -rc1. * tag 'omap-for-v3.11/fixes-for-merge-window' of git://git.kernel.org/pub/scm/linux/kernel/git/tmlind/linux-omap: ARM: OMAP2+: omap2plus_defconfig: Enable appended DTB support ARM: OMAP2+: Enable TI_EDMA in omap2plus_defconfig ARM: OMAP2+: omap2plus_defconfig: enable DRA752 thermal support by default ARM: OMAP2+: omap2plus_defconfig: enable TI bandgap driver ARM: OMAP2+: devices: remove duplicated include from devices.c ARM: OMAP3: igep0020: Set DSS pins in correct mux mode. ARM: OMAP2+: N900: enable N900-specific drivers even if device tree is enabled ARM: OMAP2+: Cocci spatch "ptr_ret.spatch" ARM: OMAP2+: Remove obsolete Makefile line ARM: OMAP5: Enable Cortex A15 errata 798181 ARM: scu: provide inline dummy functions when SCU is not present ARM: OMAP4: sleep: build OMAP4 specific functions only for OMAP4 ARM: OMAP2+: timer: initialize before using oh_name Signed-off-by: Olof Johansson <olof@lixom.net> Add/move/change conflicts in arch/arm/mach-omap2/Kconfig resolved.
Diffstat (limited to 'fs/proc/vmcore.c')
-rw-r--r--fs/proc/vmcore.c694
1 files changed, 484 insertions, 210 deletions
diff --git a/fs/proc/vmcore.c b/fs/proc/vmcore.c
index 17f7e080d7ff..28503172f2e4 100644
--- a/fs/proc/vmcore.c
+++ b/fs/proc/vmcore.c
@@ -20,6 +20,7 @@
#include <linux/init.h>
#include <linux/crash_dump.h>
#include <linux/list.h>
+#include <linux/vmalloc.h>
#include <asm/uaccess.h>
#include <asm/io.h>
#include "internal.h"
@@ -32,6 +33,10 @@ static LIST_HEAD(vmcore_list);
/* Stores the pointer to the buffer containing kernel elf core headers. */
static char *elfcorebuf;
static size_t elfcorebuf_sz;
+static size_t elfcorebuf_sz_orig;
+
+static char *elfnotes_buf;
+static size_t elfnotes_sz;
/* Total size of vmcore file. */
static u64 vmcore_size;
@@ -118,27 +123,6 @@ static ssize_t read_from_oldmem(char *buf, size_t count,
return read;
}
-/* Maps vmcore file offset to respective physical address in memroy. */
-static u64 map_offset_to_paddr(loff_t offset, struct list_head *vc_list,
- struct vmcore **m_ptr)
-{
- struct vmcore *m;
- u64 paddr;
-
- list_for_each_entry(m, vc_list, list) {
- u64 start, end;
- start = m->offset;
- end = m->offset + m->size - 1;
- if (offset >= start && offset <= end) {
- paddr = m->paddr + offset - start;
- *m_ptr = m;
- return paddr;
- }
- }
- *m_ptr = NULL;
- return 0;
-}
-
/* Read from the ELF header and then the crash dump. On error, negative value is
* returned otherwise number of bytes read are returned.
*/
@@ -147,8 +131,8 @@ static ssize_t read_vmcore(struct file *file, char __user *buffer,
{
ssize_t acc = 0, tmp;
size_t tsz;
- u64 start, nr_bytes;
- struct vmcore *curr_m = NULL;
+ u64 start;
+ struct vmcore *m = NULL;
if (buflen == 0 || *fpos >= vmcore_size)
return 0;
@@ -159,9 +143,7 @@ static ssize_t read_vmcore(struct file *file, char __user *buffer,
/* Read ELF core header */
if (*fpos < elfcorebuf_sz) {
- tsz = elfcorebuf_sz - *fpos;
- if (buflen < tsz)
- tsz = buflen;
+ tsz = min(elfcorebuf_sz - (size_t)*fpos, buflen);
if (copy_to_user(buffer, elfcorebuf + *fpos, tsz))
return -EFAULT;
buflen -= tsz;
@@ -174,39 +156,161 @@ static ssize_t read_vmcore(struct file *file, char __user *buffer,
return acc;
}
- start = map_offset_to_paddr(*fpos, &vmcore_list, &curr_m);
- if (!curr_m)
- return -EINVAL;
-
- while (buflen) {
- tsz = min_t(size_t, buflen, PAGE_SIZE - (start & ~PAGE_MASK));
+ /* Read Elf note segment */
+ if (*fpos < elfcorebuf_sz + elfnotes_sz) {
+ void *kaddr;
- /* Calculate left bytes in current memory segment. */
- nr_bytes = (curr_m->size - (start - curr_m->paddr));
- if (tsz > nr_bytes)
- tsz = nr_bytes;
-
- tmp = read_from_oldmem(buffer, tsz, &start, 1);
- if (tmp < 0)
- return tmp;
+ tsz = min(elfcorebuf_sz + elfnotes_sz - (size_t)*fpos, buflen);
+ kaddr = elfnotes_buf + *fpos - elfcorebuf_sz;
+ if (copy_to_user(buffer, kaddr, tsz))
+ return -EFAULT;
buflen -= tsz;
*fpos += tsz;
buffer += tsz;
acc += tsz;
- if (start >= (curr_m->paddr + curr_m->size)) {
- if (curr_m->list.next == &vmcore_list)
- return acc; /*EOF*/
- curr_m = list_entry(curr_m->list.next,
- struct vmcore, list);
- start = curr_m->paddr;
+
+ /* leave now if filled buffer already */
+ if (buflen == 0)
+ return acc;
+ }
+
+ list_for_each_entry(m, &vmcore_list, list) {
+ if (*fpos < m->offset + m->size) {
+ tsz = min_t(size_t, m->offset + m->size - *fpos, buflen);
+ start = m->paddr + *fpos - m->offset;
+ tmp = read_from_oldmem(buffer, tsz, &start, 1);
+ if (tmp < 0)
+ return tmp;
+ buflen -= tsz;
+ *fpos += tsz;
+ buffer += tsz;
+ acc += tsz;
+
+ /* leave now if filled buffer already */
+ if (buflen == 0)
+ return acc;
}
}
+
return acc;
}
+/**
+ * alloc_elfnotes_buf - allocate buffer for ELF note segment in
+ * vmalloc memory
+ *
+ * @notes_sz: size of buffer
+ *
+ * If CONFIG_MMU is defined, use vmalloc_user() to allow users to mmap
+ * the buffer to user-space by means of remap_vmalloc_range().
+ *
+ * If CONFIG_MMU is not defined, use vzalloc() since mmap_vmcore() is
+ * disabled and there's no need to allow users to mmap the buffer.
+ */
+static inline char *alloc_elfnotes_buf(size_t notes_sz)
+{
+#ifdef CONFIG_MMU
+ return vmalloc_user(notes_sz);
+#else
+ return vzalloc(notes_sz);
+#endif
+}
+
+/*
+ * Disable mmap_vmcore() if CONFIG_MMU is not defined. MMU is
+ * essential for mmap_vmcore() in order to map physically
+ * non-contiguous objects (ELF header, ELF note segment and memory
+ * regions in the 1st kernel pointed to by PT_LOAD entries) into
+ * virtually contiguous user-space in ELF layout.
+ */
+#ifdef CONFIG_MMU
+static int mmap_vmcore(struct file *file, struct vm_area_struct *vma)
+{
+ size_t size = vma->vm_end - vma->vm_start;
+ u64 start, end, len, tsz;
+ struct vmcore *m;
+
+ start = (u64)vma->vm_pgoff << PAGE_SHIFT;
+ end = start + size;
+
+ if (size > vmcore_size || end > vmcore_size)
+ return -EINVAL;
+
+ if (vma->vm_flags & (VM_WRITE | VM_EXEC))
+ return -EPERM;
+
+ vma->vm_flags &= ~(VM_MAYWRITE | VM_MAYEXEC);
+ vma->vm_flags |= VM_MIXEDMAP;
+
+ len = 0;
+
+ if (start < elfcorebuf_sz) {
+ u64 pfn;
+
+ tsz = min(elfcorebuf_sz - (size_t)start, size);
+ pfn = __pa(elfcorebuf + start) >> PAGE_SHIFT;
+ if (remap_pfn_range(vma, vma->vm_start, pfn, tsz,
+ vma->vm_page_prot))
+ return -EAGAIN;
+ size -= tsz;
+ start += tsz;
+ len += tsz;
+
+ if (size == 0)
+ return 0;
+ }
+
+ if (start < elfcorebuf_sz + elfnotes_sz) {
+ void *kaddr;
+
+ tsz = min(elfcorebuf_sz + elfnotes_sz - (size_t)start, size);
+ kaddr = elfnotes_buf + start - elfcorebuf_sz;
+ if (remap_vmalloc_range_partial(vma, vma->vm_start + len,
+ kaddr, tsz))
+ goto fail;
+ size -= tsz;
+ start += tsz;
+ len += tsz;
+
+ if (size == 0)
+ return 0;
+ }
+
+ list_for_each_entry(m, &vmcore_list, list) {
+ if (start < m->offset + m->size) {
+ u64 paddr = 0;
+
+ tsz = min_t(size_t, m->offset + m->size - start, size);
+ paddr = m->paddr + start - m->offset;
+ if (remap_pfn_range(vma, vma->vm_start + len,
+ paddr >> PAGE_SHIFT, tsz,
+ vma->vm_page_prot))
+ goto fail;
+ size -= tsz;
+ start += tsz;
+ len += tsz;
+
+ if (size == 0)
+ return 0;
+ }
+ }
+
+ return 0;
+fail:
+ do_munmap(vma->vm_mm, vma->vm_start, len);
+ return -EAGAIN;
+}
+#else
+static int mmap_vmcore(struct file *file, struct vm_area_struct *vma)
+{
+ return -ENOSYS;
+}
+#endif
+
static const struct file_operations proc_vmcore_operations = {
.read = read_vmcore,
.llseek = default_llseek,
+ .mmap = mmap_vmcore,
};
static struct vmcore* __init get_new_element(void)
@@ -214,61 +318,40 @@ static struct vmcore* __init get_new_element(void)
return kzalloc(sizeof(struct vmcore), GFP_KERNEL);
}
-static u64 __init get_vmcore_size_elf64(char *elfptr)
+static u64 __init get_vmcore_size(size_t elfsz, size_t elfnotesegsz,
+ struct list_head *vc_list)
{
- int i;
- u64 size;
- Elf64_Ehdr *ehdr_ptr;
- Elf64_Phdr *phdr_ptr;
-
- ehdr_ptr = (Elf64_Ehdr *)elfptr;
- phdr_ptr = (Elf64_Phdr*)(elfptr + sizeof(Elf64_Ehdr));
- size = sizeof(Elf64_Ehdr) + ((ehdr_ptr->e_phnum) * sizeof(Elf64_Phdr));
- for (i = 0; i < ehdr_ptr->e_phnum; i++) {
- size += phdr_ptr->p_memsz;
- phdr_ptr++;
- }
- return size;
-}
-
-static u64 __init get_vmcore_size_elf32(char *elfptr)
-{
- int i;
u64 size;
- Elf32_Ehdr *ehdr_ptr;
- Elf32_Phdr *phdr_ptr;
+ struct vmcore *m;
- ehdr_ptr = (Elf32_Ehdr *)elfptr;
- phdr_ptr = (Elf32_Phdr*)(elfptr + sizeof(Elf32_Ehdr));
- size = sizeof(Elf32_Ehdr) + ((ehdr_ptr->e_phnum) * sizeof(Elf32_Phdr));
- for (i = 0; i < ehdr_ptr->e_phnum; i++) {
- size += phdr_ptr->p_memsz;
- phdr_ptr++;
+ size = elfsz + elfnotesegsz;
+ list_for_each_entry(m, vc_list, list) {
+ size += m->size;
}
return size;
}
-/* Merges all the PT_NOTE headers into one. */
-static int __init merge_note_headers_elf64(char *elfptr, size_t *elfsz,
- struct list_head *vc_list)
+/**
+ * update_note_header_size_elf64 - update p_memsz member of each PT_NOTE entry
+ *
+ * @ehdr_ptr: ELF header
+ *
+ * This function updates p_memsz member of each PT_NOTE entry in the
+ * program header table pointed to by @ehdr_ptr to real size of ELF
+ * note segment.
+ */
+static int __init update_note_header_size_elf64(const Elf64_Ehdr *ehdr_ptr)
{
- int i, nr_ptnote=0, rc=0;
- char *tmp;
- Elf64_Ehdr *ehdr_ptr;
- Elf64_Phdr phdr, *phdr_ptr;
+ int i, rc=0;
+ Elf64_Phdr *phdr_ptr;
Elf64_Nhdr *nhdr_ptr;
- u64 phdr_sz = 0, note_off;
- ehdr_ptr = (Elf64_Ehdr *)elfptr;
- phdr_ptr = (Elf64_Phdr*)(elfptr + sizeof(Elf64_Ehdr));
+ phdr_ptr = (Elf64_Phdr *)(ehdr_ptr + 1);
for (i = 0; i < ehdr_ptr->e_phnum; i++, phdr_ptr++) {
- int j;
void *notes_section;
- struct vmcore *new;
u64 offset, max_sz, sz, real_sz = 0;
if (phdr_ptr->p_type != PT_NOTE)
continue;
- nr_ptnote++;
max_sz = phdr_ptr->p_memsz;
offset = phdr_ptr->p_offset;
notes_section = kmalloc(max_sz, GFP_KERNEL);
@@ -280,7 +363,7 @@ static int __init merge_note_headers_elf64(char *elfptr, size_t *elfsz,
return rc;
}
nhdr_ptr = notes_section;
- for (j = 0; j < max_sz; j += sz) {
+ while (real_sz < max_sz) {
if (nhdr_ptr->n_namesz == 0)
break;
sz = sizeof(Elf64_Nhdr) +
@@ -289,26 +372,122 @@ static int __init merge_note_headers_elf64(char *elfptr, size_t *elfsz,
real_sz += sz;
nhdr_ptr = (Elf64_Nhdr*)((char*)nhdr_ptr + sz);
}
-
- /* Add this contiguous chunk of notes section to vmcore list.*/
- new = get_new_element();
- if (!new) {
- kfree(notes_section);
- return -ENOMEM;
- }
- new->paddr = phdr_ptr->p_offset;
- new->size = real_sz;
- list_add_tail(&new->list, vc_list);
- phdr_sz += real_sz;
kfree(notes_section);
+ phdr_ptr->p_memsz = real_sz;
+ }
+
+ return 0;
+}
+
+/**
+ * get_note_number_and_size_elf64 - get the number of PT_NOTE program
+ * headers and sum of real size of their ELF note segment headers and
+ * data.
+ *
+ * @ehdr_ptr: ELF header
+ * @nr_ptnote: buffer for the number of PT_NOTE program headers
+ * @sz_ptnote: buffer for size of unique PT_NOTE program header
+ *
+ * This function is used to merge multiple PT_NOTE program headers
+ * into a unique single one. The resulting unique entry will have
+ * @sz_ptnote in its phdr->p_mem.
+ *
+ * It is assumed that program headers with PT_NOTE type pointed to by
+ * @ehdr_ptr has already been updated by update_note_header_size_elf64
+ * and each of PT_NOTE program headers has actual ELF note segment
+ * size in its p_memsz member.
+ */
+static int __init get_note_number_and_size_elf64(const Elf64_Ehdr *ehdr_ptr,
+ int *nr_ptnote, u64 *sz_ptnote)
+{
+ int i;
+ Elf64_Phdr *phdr_ptr;
+
+ *nr_ptnote = *sz_ptnote = 0;
+
+ phdr_ptr = (Elf64_Phdr *)(ehdr_ptr + 1);
+ for (i = 0; i < ehdr_ptr->e_phnum; i++, phdr_ptr++) {
+ if (phdr_ptr->p_type != PT_NOTE)
+ continue;
+ *nr_ptnote += 1;
+ *sz_ptnote += phdr_ptr->p_memsz;
+ }
+
+ return 0;
+}
+
+/**
+ * copy_notes_elf64 - copy ELF note segments in a given buffer
+ *
+ * @ehdr_ptr: ELF header
+ * @notes_buf: buffer into which ELF note segments are copied
+ *
+ * This function is used to copy ELF note segment in the 1st kernel
+ * into the buffer @notes_buf in the 2nd kernel. It is assumed that
+ * size of the buffer @notes_buf is equal to or larger than sum of the
+ * real ELF note segment headers and data.
+ *
+ * It is assumed that program headers with PT_NOTE type pointed to by
+ * @ehdr_ptr has already been updated by update_note_header_size_elf64
+ * and each of PT_NOTE program headers has actual ELF note segment
+ * size in its p_memsz member.
+ */
+static int __init copy_notes_elf64(const Elf64_Ehdr *ehdr_ptr, char *notes_buf)
+{
+ int i, rc=0;
+ Elf64_Phdr *phdr_ptr;
+
+ phdr_ptr = (Elf64_Phdr*)(ehdr_ptr + 1);
+
+ for (i = 0; i < ehdr_ptr->e_phnum; i++, phdr_ptr++) {
+ u64 offset;
+ if (phdr_ptr->p_type != PT_NOTE)
+ continue;
+ offset = phdr_ptr->p_offset;
+ rc = read_from_oldmem(notes_buf, phdr_ptr->p_memsz, &offset, 0);
+ if (rc < 0)
+ return rc;
+ notes_buf += phdr_ptr->p_memsz;
}
+ return 0;
+}
+
+/* Merges all the PT_NOTE headers into one. */
+static int __init merge_note_headers_elf64(char *elfptr, size_t *elfsz,
+ char **notes_buf, size_t *notes_sz)
+{
+ int i, nr_ptnote=0, rc=0;
+ char *tmp;
+ Elf64_Ehdr *ehdr_ptr;
+ Elf64_Phdr phdr;
+ u64 phdr_sz = 0, note_off;
+
+ ehdr_ptr = (Elf64_Ehdr *)elfptr;
+
+ rc = update_note_header_size_elf64(ehdr_ptr);
+ if (rc < 0)
+ return rc;
+
+ rc = get_note_number_and_size_elf64(ehdr_ptr, &nr_ptnote, &phdr_sz);
+ if (rc < 0)
+ return rc;
+
+ *notes_sz = roundup(phdr_sz, PAGE_SIZE);
+ *notes_buf = alloc_elfnotes_buf(*notes_sz);
+ if (!*notes_buf)
+ return -ENOMEM;
+
+ rc = copy_notes_elf64(ehdr_ptr, *notes_buf);
+ if (rc < 0)
+ return rc;
+
/* Prepare merged PT_NOTE program header. */
phdr.p_type = PT_NOTE;
phdr.p_flags = 0;
note_off = sizeof(Elf64_Ehdr) +
(ehdr_ptr->e_phnum - nr_ptnote +1) * sizeof(Elf64_Phdr);
- phdr.p_offset = note_off;
+ phdr.p_offset = roundup(note_off, PAGE_SIZE);
phdr.p_vaddr = phdr.p_paddr = 0;
phdr.p_filesz = phdr.p_memsz = phdr_sz;
phdr.p_align = 0;
@@ -322,6 +501,8 @@ static int __init merge_note_headers_elf64(char *elfptr, size_t *elfsz,
i = (nr_ptnote - 1) * sizeof(Elf64_Phdr);
*elfsz = *elfsz - i;
memmove(tmp, tmp+i, ((*elfsz)-sizeof(Elf64_Ehdr)-sizeof(Elf64_Phdr)));
+ memset(elfptr + *elfsz, 0, i);
+ *elfsz = roundup(*elfsz, PAGE_SIZE);
/* Modify e_phnum to reflect merged headers. */
ehdr_ptr->e_phnum = ehdr_ptr->e_phnum - nr_ptnote + 1;
@@ -329,27 +510,27 @@ static int __init merge_note_headers_elf64(char *elfptr, size_t *elfsz,
return 0;
}
-/* Merges all the PT_NOTE headers into one. */
-static int __init merge_note_headers_elf32(char *elfptr, size_t *elfsz,
- struct list_head *vc_list)
+/**
+ * update_note_header_size_elf32 - update p_memsz member of each PT_NOTE entry
+ *
+ * @ehdr_ptr: ELF header
+ *
+ * This function updates p_memsz member of each PT_NOTE entry in the
+ * program header table pointed to by @ehdr_ptr to real size of ELF
+ * note segment.
+ */
+static int __init update_note_header_size_elf32(const Elf32_Ehdr *ehdr_ptr)
{
- int i, nr_ptnote=0, rc=0;
- char *tmp;
- Elf32_Ehdr *ehdr_ptr;
- Elf32_Phdr phdr, *phdr_ptr;
+ int i, rc=0;
+ Elf32_Phdr *phdr_ptr;
Elf32_Nhdr *nhdr_ptr;
- u64 phdr_sz = 0, note_off;
- ehdr_ptr = (Elf32_Ehdr *)elfptr;
- phdr_ptr = (Elf32_Phdr*)(elfptr + sizeof(Elf32_Ehdr));
+ phdr_ptr = (Elf32_Phdr *)(ehdr_ptr + 1);
for (i = 0; i < ehdr_ptr->e_phnum; i++, phdr_ptr++) {
- int j;
void *notes_section;
- struct vmcore *new;
u64 offset, max_sz, sz, real_sz = 0;
if (phdr_ptr->p_type != PT_NOTE)
continue;
- nr_ptnote++;
max_sz = phdr_ptr->p_memsz;
offset = phdr_ptr->p_offset;
notes_section = kmalloc(max_sz, GFP_KERNEL);
@@ -361,7 +542,7 @@ static int __init merge_note_headers_elf32(char *elfptr, size_t *elfsz,
return rc;
}
nhdr_ptr = notes_section;
- for (j = 0; j < max_sz; j += sz) {
+ while (real_sz < max_sz) {
if (nhdr_ptr->n_namesz == 0)
break;
sz = sizeof(Elf32_Nhdr) +
@@ -370,26 +551,122 @@ static int __init merge_note_headers_elf32(char *elfptr, size_t *elfsz,
real_sz += sz;
nhdr_ptr = (Elf32_Nhdr*)((char*)nhdr_ptr + sz);
}
-
- /* Add this contiguous chunk of notes section to vmcore list.*/
- new = get_new_element();
- if (!new) {
- kfree(notes_section);
- return -ENOMEM;
- }
- new->paddr = phdr_ptr->p_offset;
- new->size = real_sz;
- list_add_tail(&new->list, vc_list);
- phdr_sz += real_sz;
kfree(notes_section);
+ phdr_ptr->p_memsz = real_sz;
+ }
+
+ return 0;
+}
+
+/**
+ * get_note_number_and_size_elf32 - get the number of PT_NOTE program
+ * headers and sum of real size of their ELF note segment headers and
+ * data.
+ *
+ * @ehdr_ptr: ELF header
+ * @nr_ptnote: buffer for the number of PT_NOTE program headers
+ * @sz_ptnote: buffer for size of unique PT_NOTE program header
+ *
+ * This function is used to merge multiple PT_NOTE program headers
+ * into a unique single one. The resulting unique entry will have
+ * @sz_ptnote in its phdr->p_mem.
+ *
+ * It is assumed that program headers with PT_NOTE type pointed to by
+ * @ehdr_ptr has already been updated by update_note_header_size_elf32
+ * and each of PT_NOTE program headers has actual ELF note segment
+ * size in its p_memsz member.
+ */
+static int __init get_note_number_and_size_elf32(const Elf32_Ehdr *ehdr_ptr,
+ int *nr_ptnote, u64 *sz_ptnote)
+{
+ int i;
+ Elf32_Phdr *phdr_ptr;
+
+ *nr_ptnote = *sz_ptnote = 0;
+
+ phdr_ptr = (Elf32_Phdr *)(ehdr_ptr + 1);
+ for (i = 0; i < ehdr_ptr->e_phnum; i++, phdr_ptr++) {
+ if (phdr_ptr->p_type != PT_NOTE)
+ continue;
+ *nr_ptnote += 1;
+ *sz_ptnote += phdr_ptr->p_memsz;
+ }
+
+ return 0;
+}
+
+/**
+ * copy_notes_elf32 - copy ELF note segments in a given buffer
+ *
+ * @ehdr_ptr: ELF header
+ * @notes_buf: buffer into which ELF note segments are copied
+ *
+ * This function is used to copy ELF note segment in the 1st kernel
+ * into the buffer @notes_buf in the 2nd kernel. It is assumed that
+ * size of the buffer @notes_buf is equal to or larger than sum of the
+ * real ELF note segment headers and data.
+ *
+ * It is assumed that program headers with PT_NOTE type pointed to by
+ * @ehdr_ptr has already been updated by update_note_header_size_elf32
+ * and each of PT_NOTE program headers has actual ELF note segment
+ * size in its p_memsz member.
+ */
+static int __init copy_notes_elf32(const Elf32_Ehdr *ehdr_ptr, char *notes_buf)
+{
+ int i, rc=0;
+ Elf32_Phdr *phdr_ptr;
+
+ phdr_ptr = (Elf32_Phdr*)(ehdr_ptr + 1);
+
+ for (i = 0; i < ehdr_ptr->e_phnum; i++, phdr_ptr++) {
+ u64 offset;
+ if (phdr_ptr->p_type != PT_NOTE)
+ continue;
+ offset = phdr_ptr->p_offset;
+ rc = read_from_oldmem(notes_buf, phdr_ptr->p_memsz, &offset, 0);
+ if (rc < 0)
+ return rc;
+ notes_buf += phdr_ptr->p_memsz;
}
+ return 0;
+}
+
+/* Merges all the PT_NOTE headers into one. */
+static int __init merge_note_headers_elf32(char *elfptr, size_t *elfsz,
+ char **notes_buf, size_t *notes_sz)
+{
+ int i, nr_ptnote=0, rc=0;
+ char *tmp;
+ Elf32_Ehdr *ehdr_ptr;
+ Elf32_Phdr phdr;
+ u64 phdr_sz = 0, note_off;
+
+ ehdr_ptr = (Elf32_Ehdr *)elfptr;
+
+ rc = update_note_header_size_elf32(ehdr_ptr);
+ if (rc < 0)
+ return rc;
+
+ rc = get_note_number_and_size_elf32(ehdr_ptr, &nr_ptnote, &phdr_sz);
+ if (rc < 0)
+ return rc;
+
+ *notes_sz = roundup(phdr_sz, PAGE_SIZE);
+ *notes_buf = alloc_elfnotes_buf(*notes_sz);
+ if (!*notes_buf)
+ return -ENOMEM;
+
+ rc = copy_notes_elf32(ehdr_ptr, *notes_buf);
+ if (rc < 0)
+ return rc;
+
/* Prepare merged PT_NOTE program header. */
phdr.p_type = PT_NOTE;
phdr.p_flags = 0;
note_off = sizeof(Elf32_Ehdr) +
(ehdr_ptr->e_phnum - nr_ptnote +1) * sizeof(Elf32_Phdr);
- phdr.p_offset = note_off;
+ phdr.p_offset = roundup(note_off, PAGE_SIZE);
phdr.p_vaddr = phdr.p_paddr = 0;
phdr.p_filesz = phdr.p_memsz = phdr_sz;
phdr.p_align = 0;
@@ -403,6 +680,8 @@ static int __init merge_note_headers_elf32(char *elfptr, size_t *elfsz,
i = (nr_ptnote - 1) * sizeof(Elf32_Phdr);
*elfsz = *elfsz - i;
memmove(tmp, tmp+i, ((*elfsz)-sizeof(Elf32_Ehdr)-sizeof(Elf32_Phdr)));
+ memset(elfptr + *elfsz, 0, i);
+ *elfsz = roundup(*elfsz, PAGE_SIZE);
/* Modify e_phnum to reflect merged headers. */
ehdr_ptr->e_phnum = ehdr_ptr->e_phnum - nr_ptnote + 1;
@@ -414,6 +693,7 @@ static int __init merge_note_headers_elf32(char *elfptr, size_t *elfsz,
* the new offset fields of exported program headers. */
static int __init process_ptload_program_headers_elf64(char *elfptr,
size_t elfsz,
+ size_t elfnotes_sz,
struct list_head *vc_list)
{
int i;
@@ -425,32 +705,38 @@ static int __init process_ptload_program_headers_elf64(char *elfptr,
ehdr_ptr = (Elf64_Ehdr *)elfptr;
phdr_ptr = (Elf64_Phdr*)(elfptr + sizeof(Elf64_Ehdr)); /* PT_NOTE hdr */
- /* First program header is PT_NOTE header. */
- vmcore_off = sizeof(Elf64_Ehdr) +
- (ehdr_ptr->e_phnum) * sizeof(Elf64_Phdr) +
- phdr_ptr->p_memsz; /* Note sections */
+ /* Skip Elf header, program headers and Elf note segment. */
+ vmcore_off = elfsz + elfnotes_sz;
for (i = 0; i < ehdr_ptr->e_phnum; i++, phdr_ptr++) {
+ u64 paddr, start, end, size;
+
if (phdr_ptr->p_type != PT_LOAD)
continue;
+ paddr = phdr_ptr->p_offset;
+ start = rounddown(paddr, PAGE_SIZE);
+ end = roundup(paddr + phdr_ptr->p_memsz, PAGE_SIZE);
+ size = end - start;
+
/* Add this contiguous chunk of memory to vmcore list.*/
new = get_new_element();
if (!new)
return -ENOMEM;
- new->paddr = phdr_ptr->p_offset;
- new->size = phdr_ptr->p_memsz;
+ new->paddr = start;
+ new->size = size;
list_add_tail(&new->list, vc_list);
/* Update the program header offset. */
- phdr_ptr->p_offset = vmcore_off;
- vmcore_off = vmcore_off + phdr_ptr->p_memsz;
+ phdr_ptr->p_offset = vmcore_off + (paddr - start);
+ vmcore_off = vmcore_off + size;
}
return 0;
}
static int __init process_ptload_program_headers_elf32(char *elfptr,
size_t elfsz,
+ size_t elfnotes_sz,
struct list_head *vc_list)
{
int i;
@@ -462,43 +748,44 @@ static int __init process_ptload_program_headers_elf32(char *elfptr,
ehdr_ptr = (Elf32_Ehdr *)elfptr;
phdr_ptr = (Elf32_Phdr*)(elfptr + sizeof(Elf32_Ehdr)); /* PT_NOTE hdr */
- /* First program header is PT_NOTE header. */
- vmcore_off = sizeof(Elf32_Ehdr) +
- (ehdr_ptr->e_phnum) * sizeof(Elf32_Phdr) +
- phdr_ptr->p_memsz; /* Note sections */
+ /* Skip Elf header, program headers and Elf note segment. */
+ vmcore_off = elfsz + elfnotes_sz;
for (i = 0; i < ehdr_ptr->e_phnum; i++, phdr_ptr++) {
+ u64 paddr, start, end, size;
+
if (phdr_ptr->p_type != PT_LOAD)
continue;
+ paddr = phdr_ptr->p_offset;
+ start = rounddown(paddr, PAGE_SIZE);
+ end = roundup(paddr + phdr_ptr->p_memsz, PAGE_SIZE);
+ size = end - start;
+
/* Add this contiguous chunk of memory to vmcore list.*/
new = get_new_element();
if (!new)
return -ENOMEM;
- new->paddr = phdr_ptr->p_offset;
- new->size = phdr_ptr->p_memsz;
+ new->paddr = start;
+ new->size = size;
list_add_tail(&new->list, vc_list);
/* Update the program header offset */
- phdr_ptr->p_offset = vmcore_off;
- vmcore_off = vmcore_off + phdr_ptr->p_memsz;
+ phdr_ptr->p_offset = vmcore_off + (paddr - start);
+ vmcore_off = vmcore_off + size;
}
return 0;
}
/* Sets offset fields of vmcore elements. */
-static void __init set_vmcore_list_offsets_elf64(char *elfptr,
- struct list_head *vc_list)
+static void __init set_vmcore_list_offsets(size_t elfsz, size_t elfnotes_sz,
+ struct list_head *vc_list)
{
loff_t vmcore_off;
- Elf64_Ehdr *ehdr_ptr;
struct vmcore *m;
- ehdr_ptr = (Elf64_Ehdr *)elfptr;
-
- /* Skip Elf header and program headers. */
- vmcore_off = sizeof(Elf64_Ehdr) +
- (ehdr_ptr->e_phnum) * sizeof(Elf64_Phdr);
+ /* Skip Elf header, program headers and Elf note segment. */
+ vmcore_off = elfsz + elfnotes_sz;
list_for_each_entry(m, vc_list, list) {
m->offset = vmcore_off;
@@ -506,24 +793,12 @@ static void __init set_vmcore_list_offsets_elf64(char *elfptr,
}
}
-/* Sets offset fields of vmcore elements. */
-static void __init set_vmcore_list_offsets_elf32(char *elfptr,
- struct list_head *vc_list)
+static void free_elfcorebuf(void)
{
- loff_t vmcore_off;
- Elf32_Ehdr *ehdr_ptr;
- struct vmcore *m;
-
- ehdr_ptr = (Elf32_Ehdr *)elfptr;
-
- /* Skip Elf header and program headers. */
- vmcore_off = sizeof(Elf32_Ehdr) +
- (ehdr_ptr->e_phnum) * sizeof(Elf32_Phdr);
-
- list_for_each_entry(m, vc_list, list) {
- m->offset = vmcore_off;
- vmcore_off += m->size;
- }
+ free_pages((unsigned long)elfcorebuf, get_order(elfcorebuf_sz_orig));
+ elfcorebuf = NULL;
+ vfree(elfnotes_buf);
+ elfnotes_buf = NULL;
}
static int __init parse_crash_elf64_headers(void)
@@ -554,31 +829,32 @@ static int __init parse_crash_elf64_headers(void)
}
/* Read in all elf headers. */
- elfcorebuf_sz = sizeof(Elf64_Ehdr) + ehdr.e_phnum * sizeof(Elf64_Phdr);
- elfcorebuf = kmalloc(elfcorebuf_sz, GFP_KERNEL);
+ elfcorebuf_sz_orig = sizeof(Elf64_Ehdr) +
+ ehdr.e_phnum * sizeof(Elf64_Phdr);
+ elfcorebuf_sz = elfcorebuf_sz_orig;
+ elfcorebuf = (void *)__get_free_pages(GFP_KERNEL | __GFP_ZERO,
+ get_order(elfcorebuf_sz_orig));
if (!elfcorebuf)
return -ENOMEM;
addr = elfcorehdr_addr;
- rc = read_from_oldmem(elfcorebuf, elfcorebuf_sz, &addr, 0);
- if (rc < 0) {
- kfree(elfcorebuf);
- return rc;
- }
+ rc = read_from_oldmem(elfcorebuf, elfcorebuf_sz_orig, &addr, 0);
+ if (rc < 0)
+ goto fail;
/* Merge all PT_NOTE headers into one. */
- rc = merge_note_headers_elf64(elfcorebuf, &elfcorebuf_sz, &vmcore_list);
- if (rc) {
- kfree(elfcorebuf);
- return rc;
- }
+ rc = merge_note_headers_elf64(elfcorebuf, &elfcorebuf_sz,
+ &elfnotes_buf, &elfnotes_sz);
+ if (rc)
+ goto fail;
rc = process_ptload_program_headers_elf64(elfcorebuf, elfcorebuf_sz,
- &vmcore_list);
- if (rc) {
- kfree(elfcorebuf);
- return rc;
- }
- set_vmcore_list_offsets_elf64(elfcorebuf, &vmcore_list);
+ elfnotes_sz, &vmcore_list);
+ if (rc)
+ goto fail;
+ set_vmcore_list_offsets(elfcorebuf_sz, elfnotes_sz, &vmcore_list);
return 0;
+fail:
+ free_elfcorebuf();
+ return rc;
}
static int __init parse_crash_elf32_headers(void)
@@ -609,31 +885,31 @@ static int __init parse_crash_elf32_headers(void)
}
/* Read in all elf headers. */
- elfcorebuf_sz = sizeof(Elf32_Ehdr) + ehdr.e_phnum * sizeof(Elf32_Phdr);
- elfcorebuf = kmalloc(elfcorebuf_sz, GFP_KERNEL);
+ elfcorebuf_sz_orig = sizeof(Elf32_Ehdr) + ehdr.e_phnum * sizeof(Elf32_Phdr);
+ elfcorebuf_sz = elfcorebuf_sz_orig;
+ elfcorebuf = (void *)__get_free_pages(GFP_KERNEL | __GFP_ZERO,
+ get_order(elfcorebuf_sz_orig));
if (!elfcorebuf)
return -ENOMEM;
addr = elfcorehdr_addr;
- rc = read_from_oldmem(elfcorebuf, elfcorebuf_sz, &addr, 0);
- if (rc < 0) {
- kfree(elfcorebuf);
- return rc;
- }
+ rc = read_from_oldmem(elfcorebuf, elfcorebuf_sz_orig, &addr, 0);
+ if (rc < 0)
+ goto fail;
/* Merge all PT_NOTE headers into one. */
- rc = merge_note_headers_elf32(elfcorebuf, &elfcorebuf_sz, &vmcore_list);
- if (rc) {
- kfree(elfcorebuf);
- return rc;
- }
+ rc = merge_note_headers_elf32(elfcorebuf, &elfcorebuf_sz,
+ &elfnotes_buf, &elfnotes_sz);
+ if (rc)
+ goto fail;
rc = process_ptload_program_headers_elf32(elfcorebuf, elfcorebuf_sz,
- &vmcore_list);
- if (rc) {
- kfree(elfcorebuf);
- return rc;
- }
- set_vmcore_list_offsets_elf32(elfcorebuf, &vmcore_list);
+ elfnotes_sz, &vmcore_list);
+ if (rc)
+ goto fail;
+ set_vmcore_list_offsets(elfcorebuf_sz, elfnotes_sz, &vmcore_list);
return 0;
+fail:
+ free_elfcorebuf();
+ return rc;
}
static int __init parse_crash_elf_headers(void)
@@ -655,20 +931,19 @@ static int __init parse_crash_elf_headers(void)
rc = parse_crash_elf64_headers();
if (rc)
return rc;
-
- /* Determine vmcore size. */
- vmcore_size = get_vmcore_size_elf64(elfcorebuf);
} else if (e_ident[EI_CLASS] == ELFCLASS32) {
rc = parse_crash_elf32_headers();
if (rc)
return rc;
-
- /* Determine vmcore size. */
- vmcore_size = get_vmcore_size_elf32(elfcorebuf);
} else {
pr_warn("Warning: Core image elf header is not sane\n");
return -EINVAL;
}
+
+ /* Determine vmcore size. */
+ vmcore_size = get_vmcore_size(elfcorebuf_sz, elfnotes_sz,
+ &vmcore_list);
+
return 0;
}
@@ -711,7 +986,6 @@ void vmcore_cleanup(void)
list_del(&m->list);
kfree(m);
}
- kfree(elfcorebuf);
- elfcorebuf = NULL;
+ free_elfcorebuf();
}
EXPORT_SYMBOL_GPL(vmcore_cleanup);