Brad Bishop | 1a4b7ee | 2018-12-16 17:11:34 -0800 | [diff] [blame^] | 1 | From 3393a2e544818f0bd1887c13f28a76ad60c2df98 Mon Sep 17 00:00:00 2001 |
| 2 | From: Robert Yang <liezhi.yang@windriver.com> |
| 3 | Date: Thu, 16 Aug 2018 09:58:26 +0800 |
| 4 | Subject: [PATCH] libelf/elf_end.c: check data_list.data.d.d_buf before free it |
| 5 | |
| 6 | The one which actually saves the data is data_list.data.d.d_buf, so check it |
| 7 | before free rawdata_base. |
| 8 | |
| 9 | This can fix a segmentation fault when prelink libqb_1.0.3: |
| 10 | prelink: /usr/lib/libqb.so.0.18.2: Symbol section index outside of section numbers |
| 11 | |
| 12 | The segmentation fault happens when prelink call elf_end(). |
| 13 | |
| 14 | Upstream-Status: Submitted [https://sourceware.org/ml/elfutils-devel/2018-q3/msg00085.html] |
| 15 | |
| 16 | Signed-off-by: Robert Yang <liezhi.yang@windriver.com> |
| 17 | --- |
| 18 | libelf/elf_end.c | 6 ++++-- |
| 19 | 1 file changed, 4 insertions(+), 2 deletions(-) |
| 20 | |
| 21 | diff --git a/libelf/elf_end.c b/libelf/elf_end.c |
| 22 | index 160f0b8..5280a70 100644 |
| 23 | --- a/libelf/elf_end.c |
| 24 | +++ b/libelf/elf_end.c |
| 25 | @@ -160,14 +160,16 @@ elf_end (Elf *elf) |
| 26 | architecture doesn't require overly stringent |
| 27 | alignment the raw data buffer is the same as the |
| 28 | one used for presenting to the caller. */ |
| 29 | - if (scn->data_base != scn->rawdata_base) |
| 30 | + if ((scn->data_base != scn->rawdata_base) |
| 31 | + && (scn->data_list.data.d.d_buf != NULL)) |
| 32 | free (scn->data_base); |
| 33 | |
| 34 | /* The section data is allocated if we couldn't mmap |
| 35 | the file. Or if we had to decompress. */ |
| 36 | - if (elf->map_address == NULL |
| 37 | + if ((elf->map_address == NULL |
| 38 | || scn->rawdata_base == scn->zdata_base |
| 39 | || (scn->flags & ELF_F_MALLOCED) != 0) |
| 40 | + && (scn->data_list.data.d.d_buf != NULL)) |
| 41 | free (scn->rawdata_base); |
| 42 | |
| 43 | /* Free the list of data buffers for the section. |
| 44 | -- |
| 45 | 2.7.4 |
| 46 | |