From 75f2de448f311807e2493f2a37a980e2d872b229 Mon Sep 17 00:00:00 2001 From: Mark Wielaard Date: Thu, 3 Nov 2022 13:38:45 +0100 Subject: readelf: Check phdr != NULL or shdr != NULL in handle_dynamic. The compiler doesn't know that when use_dynamic_segment is true, then phdr should/will be non-NULL and otherwise shdr is non-NULL. Add explicit checks to help the compiler out and in case an error is made calling the handle_dynamic function. Signed-off-by: Mark Wielaard --- src/ChangeLog | 5 +++++ src/readelf.c | 10 +++++----- 2 files changed, 10 insertions(+), 5 deletions(-) diff --git a/src/ChangeLog b/src/ChangeLog index d3399a5c..0c5ab37e 100644 --- a/src/ChangeLog +++ b/src/ChangeLog @@ -1,3 +1,8 @@ +2022-11-03 Mark Wielaard + + * readelf.c (handle_dynamic): Check phdr != NULL when + use_dynamic_segment, otherwise check shdr != NULL. + 2022-10-28 Arsen Arsenović * readelf.c (options): Add Binutils-style --syms alias. diff --git a/src/readelf.c b/src/readelf.c index 0e0b05c4..e721a209 100644 --- a/src/readelf.c +++ b/src/readelf.c @@ -1828,7 +1828,7 @@ handle_dynamic (Ebl *ebl, Elf_Scn *scn, GElf_Shdr *shdr, GElf_Phdr *phdr) size_t dyn_ents; /* Get the data of the section. */ - if (use_dynamic_segment) + if (use_dynamic_segment && phdr != NULL) data = elf_getdata_rawchunk(ebl->elf, phdr->p_offset, phdr->p_filesz, ELF_T_DYN); else @@ -1840,7 +1840,7 @@ handle_dynamic (Ebl *ebl, Elf_Scn *scn, GElf_Shdr *shdr, GElf_Phdr *phdr) /* Get the dynamic section entry number */ dyn_ents = get_dyn_ents (data); - if (!use_dynamic_segment) + if (!use_dynamic_segment && shdr != NULL) { /* Get the section header string table index. */ if (unlikely (elf_getshdrstrndx (ebl->elf, &shstrndx) < 0)) @@ -1862,7 +1862,7 @@ handle_dynamic (Ebl *ebl, Elf_Scn *scn, GElf_Shdr *shdr, GElf_Phdr *phdr) (int) shdr->sh_link, elf_strptr (ebl->elf, shstrndx, glink->sh_name)); } - else + else if (phdr != NULL) { printf (ngettext ("\ \nDynamic segment contains %lu entry:\n Addr: %#0*" PRIx64 " Offset: %#08" PRIx64 "\n", @@ -1879,7 +1879,7 @@ handle_dynamic (Ebl *ebl, Elf_Scn *scn, GElf_Shdr *shdr, GElf_Phdr *phdr) /* if --use-dynamic option is enabled, use the string table to get the related library info. */ Elf_Data *strtab_data = NULL; - if (use_dynamic_segment) + if (use_dynamic_segment && phdr != NULL) { strtab_data = get_dynscn_strtab(ebl->elf, phdr); if (strtab_data == NULL) @@ -1903,7 +1903,7 @@ handle_dynamic (Ebl *ebl, Elf_Scn *scn, GElf_Shdr *shdr, GElf_Phdr *phdr) || dyn->d_tag == DT_RPATH || dyn->d_tag == DT_RUNPATH) { - if (! use_dynamic_segment) + if (! use_dynamic_segment && shdr != NULL) name = elf_strptr (ebl->elf, shdr->sh_link, dyn->d_un.d_val); else if (dyn->d_un.d_val < strtab_data->d_size && memrchr (strtab_data->d_buf + dyn->d_un.d_val, '\0', -- cgit v1.2.1