diff options
Diffstat (limited to 'patches/0003-ld-Create-a-new-LOAD-segment-for-text-only-LOAD-segm.patch')
| -rw-r--r-- | patches/0003-ld-Create-a-new-LOAD-segment-for-text-only-LOAD-segm.patch | 161 |
1 files changed, 0 insertions, 161 deletions
diff --git a/patches/0003-ld-Create-a-new-LOAD-segment-for-text-only-LOAD-segm.patch b/patches/0003-ld-Create-a-new-LOAD-segment-for-text-only-LOAD-segm.patch deleted file mode 100644 index 307e5d062a1..00000000000 --- a/patches/0003-ld-Create-a-new-LOAD-segment-for-text-only-LOAD-segm.patch +++ /dev/null @@ -1,161 +0,0 @@ -From cc2bcf62719bc5cf63105843ced20d0952667142 Mon Sep 17 00:00:00 2001 -From: "H.J. Lu" <hjl.tools@gmail.com> -Date: Sun, 12 Nov 2017 11:34:03 -0800 -Subject: [PATCH 3/6] ld: Create a new LOAD segment for text-only LOAD segment - -When there is a text-only LOAD segment, create a new LOAD segment if the -previous section contains text and the current section doesn't or vice -versa: - -Elf file type is DYN (Shared object file) -Entry point 0x200ff0 -There are 7 program headers, starting at offset 52 - -Program Headers: - Type Offset VirtAddr PhysAddr FileSiz MemSiz Flg Align - LOAD 0x000000 0x00000000 0x00000000 0x00200 0x00200 R 0x200000 - LOAD 0x000fd0 0x00200fd0 0x00200fd0 0x0002b 0x0002b R E 0x200000 - LOAD 0x001000 0x00201000 0x00201000 0x00058 0x00058 R 0x200000 - LOAD 0x200f80 0x00400f80 0x00400f80 0x000a0 0x000a0 RW 0x200000 - DYNAMIC 0x200f80 0x00400f80 0x00400f80 0x00080 0x00080 RW 0x4 - GNU_STACK 0x000000 0x00000000 0x00000000 0x00000 0x00000 RW 0x10 - GNU_RELRO 0x200f80 0x00400f80 0x00400f80 0x00080 0x00080 R 0x1 - - Section to Segment mapping: - Segment Sections... - 00 .hash .gnu.hash .dynsym .dynstr .rela.plt - 01 .plt .text - 02 .rodata .eh_frame - 03 .dynamic .got.plt - 04 .dynamic - 05 - 06 .dynamic - -This is to prevent executing data in read-only sections as instructions. - -Also don't put a writable section in a read-only segment if there is a -RELRO segment. - -Since there are more than 2 LOAD segments, the minimum file size is -bigger than the maximum page size which is 2MB (0x200000): - --rwxr-xr-x 1 hjl hjl 2104892 Nov 12 11:53 libfoo.so - -"-z max-page-size=0x1000" can be used to reduce the maximum page size to -4KB (0x1000): - --rwxr-xr-x 1 hjl hjl 11836 Nov 12 13:22 libfoo.so - -Elf file type is DYN (Shared object file) -Entry point 0x1ff0 -There are 7 program headers, starting at offset 52 - -Program Headers: - Type Offset VirtAddr PhysAddr FileSiz MemSiz Flg Align - LOAD 0x000000 0x00000000 0x00000000 0x00200 0x00200 R 0x1000 - LOAD 0x000fd0 0x00001fd0 0x00001fd0 0x0002b 0x0002b R E 0x1000 - LOAD 0x001000 0x00002000 0x00002000 0x00058 0x00058 R 0x1000 - LOAD 0x001f80 0x00002f80 0x00002f80 0x000a0 0x000a0 RW 0x1000 - DYNAMIC 0x001f80 0x00002f80 0x00002f80 0x00080 0x00080 RW 0x4 - GNU_STACK 0x000000 0x00000000 0x00000000 0x00000 0x00000 RW 0x10 - GNU_RELRO 0x001f80 0x00002f80 0x00002f80 0x00080 0x00080 R 0x1 - - Section to Segment mapping: - Segment Sections... - 00 .hash .gnu.hash .dynsym .dynstr .rela.plt - 01 .plt .text - 02 .rodata .eh_frame - 03 .dynamic .got.plt - 04 .dynamic - 05 - 06 .dynamic - - PR ld/22393 - * elf.c (_bfd_elf_map_sections_to_segments): When there is a - text-only LOAD segment, create a new LOAD segment if the - previous section contains text and the current section doesn't - or vice versa. Don't put a writable section in a read-only - segment if there is a RELRO segment. ---- - bfd/elf.c | 32 +++++++++++++++++++++++++------- - 1 file changed, 25 insertions(+), 7 deletions(-) - -diff --git a/bfd/elf.c b/bfd/elf.c -index 694e43540f..9c5de9675c 100644 ---- a/bfd/elf.c -+++ b/bfd/elf.c -@@ -4555,6 +4555,7 @@ _bfd_elf_map_sections_to_segments (bfd *abfd, struct bfd_link_info *info) - asection **hdrpp; - bfd_boolean phdr_in_segment = TRUE; - bfd_boolean writable; -+ bfd_boolean executable; - int tls_count = 0; - asection *first_tls = NULL; - asection *first_mbind = NULL; -@@ -4643,6 +4644,7 @@ _bfd_elf_map_sections_to_segments (bfd *abfd, struct bfd_link_info *info) - if (maxpagesize == 0) - maxpagesize = 1; - writable = FALSE; -+ executable = FALSE; - dynsec = bfd_get_section_by_name (abfd, ".dynamic"); - if (dynsec != NULL - && (dynsec->flags & SEC_LOAD) == 0) -@@ -4745,18 +4747,27 @@ _bfd_elf_map_sections_to_segments (bfd *abfd, struct bfd_link_info *info) - file, then there is no other reason for a new segment. */ - new_segment = FALSE; - } -+ else if (info != NULL -+ && info->text_end > info->text_start -+ && executable != ((hdr->flags & SEC_CODE) != 0)) -+ { -+ new_segment = TRUE; -+ } - else if (! writable - && (hdr->flags & SEC_READONLY) == 0 -- && (((last_hdr->lma + last_size - 1) & -maxpagesize) -- != (hdr->lma & -maxpagesize))) -+ && ((info != NULL -+ && info->relro_end > info->relro_start) -+ || (((last_hdr->lma + last_size - 1) & -maxpagesize) -+ != (hdr->lma & -maxpagesize)))) - { - /* We don't want to put a writable section in a read only - segment, unless they are on the same page in memory -- anyhow. We already know that the last section does not -- bring us past the current section on the page, so the -- only case in which the new section is not on the same -- page as the previous section is when the previous section -- ends precisely on a page boundary. */ -+ anyhow and there is no RELRO segment. We already -+ know that the last section does not bring us past the -+ current section on the page, so the only case in which -+ the new section is not on the same page as the previous -+ section is when the previous section ends precisely on -+ a page boundary. */ - new_segment = TRUE; - } - else -@@ -4778,6 +4789,8 @@ _bfd_elf_map_sections_to_segments (bfd *abfd, struct bfd_link_info *info) - { - if ((hdr->flags & SEC_READONLY) == 0) - writable = TRUE; -+ if ((hdr->flags & SEC_CODE) != 0) -+ executable = TRUE; - last_hdr = hdr; - /* .tbss sections effectively have zero size. */ - if ((hdr->flags & (SEC_THREAD_LOCAL | SEC_LOAD)) -@@ -4803,6 +4816,11 @@ _bfd_elf_map_sections_to_segments (bfd *abfd, struct bfd_link_info *info) - else - writable = FALSE; - -+ if ((hdr->flags & SEC_CODE) == 0) -+ executable = FALSE; -+ else -+ executable = TRUE; -+ - last_hdr = hdr; - /* .tbss sections effectively have zero size. */ - if ((hdr->flags & (SEC_THREAD_LOCAL | SEC_LOAD)) != SEC_THREAD_LOCAL) --- -2.13.6 - |