To satisfy mmap() page-size boundary requirement, reound up buffer
size of ELF headers by PAGE_SIZE. The resulting value becomes offset
of ELF note segments and it's assigned in unique PT_NOTE program
header entry.
Also, some part that assumes past ELF headers' size is replaced by
this new rounded-up value.
Signed-off-by: HATAYAMA Daisuke <d.hatayama at jp.fujitsu.com>
---
fs/proc/vmcore.c | 9 +++++----
1 files changed, 5 insertions(+), 4 deletions(-)
diff --git a/fs/proc/vmcore.c b/fs/proc/vmcore.c
index 85714c3..5010ead 100644
--- a/fs/proc/vmcore.c
+++ b/fs/proc/vmcore.c
@@ -313,7 +313,7 @@ static int __init merge_note_headers_elf64(char *elfptr, size_t *elfsz,
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;
@@ -331,6 +331,8 @@ static int __init merge_note_headers_elf64(char *elfptr, size_t *elfsz,
/* Modify e_phnum to reflect merged headers. */
ehdr_ptr->e_phnum = ehdr_ptr->e_phnum - nr_ptnote + 1;
+ *elfsz = roundup(*elfsz, PAGE_SIZE);
+
return 0;
}
@@ -431,9 +433,8 @@ static int __init process_ptload_program_headers_elf64(char *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 */
+ vmcore_off = phdr_ptr->p_offset + roundup(phdr_ptr->p_memsz,
+ PAGE_SIZE);
for (i = 0; i < ehdr_ptr->e_phnum; i++, phdr_ptr++) {
if (phdr_ptr->p_type != PT_LOAD)
