Andrew Geissler | 82c905d | 2020-04-13 13:39:40 -0500 | [diff] [blame] | 1 | From 1dad746ce93928a57b2fe618c74722f710751826 Mon Sep 17 00:00:00 2001 |
| 2 | From: Mark Hatle <mark.hatle@windriver.com> |
| 3 | Date: Thu, 18 Aug 2016 14:07:58 -0500 |
| 4 | Subject: [PATCH] elf/dl-deps.c: Make _dl_build_local_scope breadth first |
| 5 | |
| 6 | According to the ELF specification: |
| 7 | |
| 8 | When resolving symbolic references, the dynamic linker examines the symbol |
| 9 | tables with a breadth-first search. |
| 10 | |
| 11 | This function was using a depth first search. By doing so the conflict |
| 12 | resolution reported to the prelinker (when LD_TRACE_PRELINKING=1 is set) |
| 13 | was incorrect. This caused problems when their were various circular |
| 14 | dependencies between libraries. The problem usually manifested itself by |
| 15 | the wrong IFUNC being executed. |
| 16 | |
| 17 | [BZ# 20488] |
| 18 | |
| 19 | Upstream-Status: Submitted [libc-alpha] |
| 20 | |
| 21 | Signed-off-by: Mark Hatle <mark.hatle@windriver.com> |
| 22 | --- |
| 23 | elf/dl-deps.c | 14 ++++++++++---- |
| 24 | 1 file changed, 10 insertions(+), 4 deletions(-) |
| 25 | |
| 26 | diff --git a/elf/dl-deps.c b/elf/dl-deps.c |
| 27 | index 5103a8a111..54cd80aaff 100644 |
| 28 | --- a/elf/dl-deps.c |
| 29 | +++ b/elf/dl-deps.c |
| 30 | @@ -73,13 +73,19 @@ _dl_build_local_scope (struct link_map **list, struct link_map *map) |
| 31 | { |
| 32 | struct link_map **p = list; |
| 33 | struct link_map **q; |
| 34 | + struct link_map **r; |
| 35 | |
| 36 | *p++ = map; |
| 37 | map->l_reserved = 1; |
| 38 | - if (map->l_initfini) |
| 39 | - for (q = map->l_initfini + 1; *q; ++q) |
| 40 | - if (! (*q)->l_reserved) |
| 41 | - p += _dl_build_local_scope (p, *q); |
| 42 | + |
| 43 | + for (r = list; r < p; ++r) |
| 44 | + if ((*r)->l_initfini) |
| 45 | + for (q = (*r)->l_initfini + 1; *q; ++q) |
| 46 | + if (! (*q)->l_reserved) |
| 47 | + { |
| 48 | + *p++ = *q; |
| 49 | + (*q)->l_reserved = 1; |
| 50 | + } |
| 51 | return p - list; |
| 52 | } |
| 53 | |