+++ /dev/null
-From 8707194a9f2f0b13e53041b03ebfdbdbd2942e43 Mon Sep 17 00:00:00 2001
-From: Mark Wielaard <mark@klomp.org>
-Date: Tue, 5 Nov 2024 23:31:14 +0100
-Subject: [PATCH 1/1] libelf: Only fetch shdr once in elf_compress[_gnu]
-
-Some compilers assume the second call to elf[32|64]_getshdr can fail
-and produce error: potential null pointer dereference. Just store the
-result of the first call and reuse (when not NULL).
-
- * libelf/elf_compress.c (elf_compress): Store getshdr result in
- a shdr union var.
- * libelf/elf_compress_gnu.c (): Likewise
-
-https://sourceware.org/bugzilla/show_bug.cgi?id=32311
-
-Signed-off-by: Mark Wielaard <mark@klomp.org>
----
- libelf/elf_compress.c | 55 +++++++++++++++++++++------------------
- libelf/elf_compress_gnu.c | 45 ++++++++++++++------------------
- 2 files changed, 48 insertions(+), 52 deletions(-)
-
---- a/libelf/elf_compress.c
-+++ b/libelf/elf_compress.c
-@@ -584,25 +584,30 @@ elf_compress (Elf_Scn *scn, int type, un
- Elf64_Xword sh_flags;
- Elf64_Word sh_type;
- Elf64_Xword sh_addralign;
-+ union shdr
-+ {
-+ Elf32_Shdr *s32;
-+ Elf64_Shdr *s64;
-+ } shdr;
- if (elfclass == ELFCLASS32)
- {
-- Elf32_Shdr *shdr = elf32_getshdr (scn);
-- if (shdr == NULL)
-+ shdr.s32 = elf32_getshdr (scn);
-+ if (shdr.s32 == NULL)
- return -1;
-
-- sh_flags = shdr->sh_flags;
-- sh_type = shdr->sh_type;
-- sh_addralign = shdr->sh_addralign;
-+ sh_flags = shdr.s32->sh_flags;
-+ sh_type = shdr.s32->sh_type;
-+ sh_addralign = shdr.s32->sh_addralign;
- }
- else
- {
-- Elf64_Shdr *shdr = elf64_getshdr (scn);
-- if (shdr == NULL)
-+ shdr.s64 = elf64_getshdr (scn);
-+ if (shdr.s64 == NULL)
- return -1;
-
-- sh_flags = shdr->sh_flags;
-- sh_type = shdr->sh_type;
-- sh_addralign = shdr->sh_addralign;
-+ sh_flags = shdr.s64->sh_flags;
-+ sh_type = shdr.s64->sh_type;
-+ sh_addralign = shdr.s64->sh_addralign;
- }
-
- if ((sh_flags & SHF_ALLOC) != 0)
-@@ -679,17 +684,17 @@ elf_compress (Elf_Scn *scn, int type, un
- correctly and ignored when SHF_COMPRESSED is set. */
- if (elfclass == ELFCLASS32)
- {
-- Elf32_Shdr *shdr = elf32_getshdr (scn);
-- shdr->sh_size = new_size;
-- shdr->sh_addralign = __libelf_type_align (ELFCLASS32, ELF_T_CHDR);
-- shdr->sh_flags |= SHF_COMPRESSED;
-+ shdr.s32->sh_size = new_size;
-+ shdr.s32->sh_addralign = __libelf_type_align (ELFCLASS32,
-+ ELF_T_CHDR);
-+ shdr.s32->sh_flags |= SHF_COMPRESSED;
- }
- else
- {
-- Elf64_Shdr *shdr = elf64_getshdr (scn);
-- shdr->sh_size = new_size;
-- shdr->sh_addralign = __libelf_type_align (ELFCLASS64, ELF_T_CHDR);
-- shdr->sh_flags |= SHF_COMPRESSED;
-+ shdr.s64->sh_size = new_size;
-+ shdr.s64->sh_addralign = __libelf_type_align (ELFCLASS64,
-+ ELF_T_CHDR);
-+ shdr.s64->sh_flags |= SHF_COMPRESSED;
- }
-
- __libelf_reset_rawdata (scn, out_buf, new_size, 1, ELF_T_CHDR);
-@@ -731,17 +736,15 @@ elf_compress (Elf_Scn *scn, int type, un
- correctly and ignored when SHF_COMPRESSED is set. */
- if (elfclass == ELFCLASS32)
- {
-- Elf32_Shdr *shdr = elf32_getshdr (scn);
-- shdr->sh_size = scn->zdata_size;
-- shdr->sh_addralign = scn->zdata_align;
-- shdr->sh_flags &= ~SHF_COMPRESSED;
-+ shdr.s32->sh_size = scn->zdata_size;
-+ shdr.s32->sh_addralign = scn->zdata_align;
-+ shdr.s32->sh_flags &= ~SHF_COMPRESSED;
- }
- else
- {
-- Elf64_Shdr *shdr = elf64_getshdr (scn);
-- shdr->sh_size = scn->zdata_size;
-- shdr->sh_addralign = scn->zdata_align;
-- shdr->sh_flags &= ~SHF_COMPRESSED;
-+ shdr.s64->sh_size = scn->zdata_size;
-+ shdr.s64->sh_addralign = scn->zdata_align;
-+ shdr.s64->sh_flags &= ~SHF_COMPRESSED;
- }
-
- __libelf_reset_rawdata (scn, scn->zdata_base,
---- a/libelf/elf_compress_gnu.c
-+++ b/libelf/elf_compress_gnu.c
-@@ -59,25 +59,30 @@ elf_compress_gnu (Elf_Scn *scn, int infl
- Elf64_Xword sh_flags;
- Elf64_Word sh_type;
- Elf64_Xword sh_addralign;
-+ union shdr
-+ {
-+ Elf32_Shdr *s32;
-+ Elf64_Shdr *s64;
-+ } shdr;
- if (elfclass == ELFCLASS32)
- {
-- Elf32_Shdr *shdr = elf32_getshdr (scn);
-- if (shdr == NULL)
-+ shdr.s32 = elf32_getshdr (scn);
-+ if (shdr.s32 == NULL)
- return -1;
-
-- sh_flags = shdr->sh_flags;
-- sh_type = shdr->sh_type;
-- sh_addralign = shdr->sh_addralign;
-+ sh_flags = shdr.s32->sh_flags;
-+ sh_type = shdr.s32->sh_type;
-+ sh_addralign = shdr.s32->sh_addralign;
- }
- else
- {
-- Elf64_Shdr *shdr = elf64_getshdr (scn);
-- if (shdr == NULL)
-+ shdr.s64 = elf64_getshdr (scn);
-+ if (shdr.s64 == NULL)
- return -1;
-
-- sh_flags = shdr->sh_flags;
-- sh_type = shdr->sh_type;
-- sh_addralign = shdr->sh_addralign;
-+ sh_flags = shdr.s64->sh_flags;
-+ sh_type = shdr.s64->sh_type;
-+ sh_addralign = shdr.s64->sh_addralign;
- }
-
- /* Allocated sections, or sections that are already are compressed
-@@ -122,15 +127,9 @@ elf_compress_gnu (Elf_Scn *scn, int infl
- sh_flags won't have a SHF_COMPRESSED hint in the GNU format.
- Just adjust the sh_size. */
- if (elfclass == ELFCLASS32)
-- {
-- Elf32_Shdr *shdr = elf32_getshdr (scn);
-- shdr->sh_size = new_size;
-- }
-+ shdr.s32->sh_size = new_size;
- else
-- {
-- Elf64_Shdr *shdr = elf64_getshdr (scn);
-- shdr->sh_size = new_size;
-- }
-+ shdr.s64->sh_size = new_size;
-
- __libelf_reset_rawdata (scn, out_buf, new_size, 1, ELF_T_BYTE);
-
-@@ -187,15 +186,9 @@ elf_compress_gnu (Elf_Scn *scn, int infl
- sh_flags won't have a SHF_COMPRESSED hint in the GNU format.
- Just adjust the sh_size. */
- if (elfclass == ELFCLASS32)
-- {
-- Elf32_Shdr *shdr = elf32_getshdr (scn);
-- shdr->sh_size = size;
-- }
-+ shdr.s32->sh_size = size;
- else
-- {
-- Elf64_Shdr *shdr = elf64_getshdr (scn);
-- shdr->sh_size = size;
-- }
-+ shdr.s64->sh_size = size;
-
- __libelf_reset_rawdata (scn, buf_out, size, sh_addralign,
- __libelf_data_type (&ehdr, sh_type,
+++ /dev/null
-strip.c: Pointer `arhdr` created at strip.c:2741 and then dereferenced without NULL-check.
-The same situation for the `arhdr` pointer at the objdump.c:313 and
-the `h` pointer at the readelf.c:13545.
-
-Triggers found by static analyzer Svace.
-
-Signed-off-by: Maks Mishin <maks.mishinFZ@gmail.com>
----
- src/objdump.c | 5 +++++
- src/readelf.c | 5 +++++
- src/strip.c | 5 +++++
- 3 files changed, 15 insertions(+)
-
---- a/src/objdump.c
-+++ b/src/objdump.c
-@@ -311,6 +311,11 @@ handle_ar (int fd, Elf *elf, const char
- {
- /* The the header for this element. */
- Elf_Arhdr *arhdr = elf_getarhdr (subelf);
-+ if (arhdr == NULL)
-+ {
-+ printf ("cannot get arhdr: %s\n", elf_errmsg (-1));
-+ exit (1);
-+ }
-
- /* Skip over the index entries. */
- if (strcmp (arhdr->ar_name, "/") != 0
---- a/src/readelf.c
-+++ b/src/readelf.c
-@@ -13543,6 +13543,11 @@ dump_archive_index (Elf *elf, const char
- as_off, fname, elf_errmsg (-1));
-
- const Elf_Arhdr *h = elf_getarhdr (subelf);
-+ if (h == NULL)
-+ {
-+ printf ("cannot get arhdr: %s\n", elf_errmsg (-1));
-+ exit (1);
-+ }
-
- printf (_("Archive member '%s' contains:\n"), h->ar_name);
-
---- a/src/strip.c
-+++ b/src/strip.c
-@@ -2739,6 +2739,11 @@ handle_ar (int fd, Elf *elf, const char
- {
- /* The the header for this element. */
- Elf_Arhdr *arhdr = elf_getarhdr (subelf);
-+ if (arhdr == NULL)
-+ {
-+ printf ("cannot get arhdr: %s\n", elf_errmsg (-1));
-+ exit (1);
-+ }
-
- if (elf_kind (subelf) == ELF_K_ELF)
- result |= handle_elf (fd, subelf, new_prefix, arhdr->ar_name, 0, NULL);
projects / thirdparty / openwrt.git / commitdiff
