[Buildroot] [PATCH 1/1] package/gcc: Initialize st in elf_is_symlink

[Buildroot] [PATCH 1/1] package/gcc: Initialize st in elf_is_symlink

[james.hilliard1 at gmail.com]

From: James Hilliard <james.hilliard1@gmail.com>

Fixes:
../../../../libsanitizer/libbacktrace/../../libbacktrace/elf.c: In function ?elf_is_symlink?:
../../../../libsanitizer/libbacktrace/../../libbacktrace/elf.c:772:21: error: ?st.st_mode? may be used uninitialized in this function [-Werror=maybe-uninitialized]
   return S_ISLNK (st.st_mode);
                     ^

Signed-off-by: James Hilliard <james.hilliard1@gmail.com>
---
 ...race-Initialize-st-in-elf_is_symlink.patch | 32 +++++++++++++++++++
 1 file changed, 32 insertions(+)
 create mode 100644 package/gcc/8.3.0/0001-libbacktrace-Initialize-st-in-elf_is_symlink.patch

diff --git a/package/gcc/8.3.0/0001-libbacktrace-Initialize-st-in-elf_is_symlink.patch b/package/gcc/8.3.0/0001-libbacktrace-Initialize-st-in-elf_is_symlink.patch
new file mode 100644
index 0000000000..22a6c38209
--- /dev/null
+++ b/package/gcc/8.3.0/0001-libbacktrace-Initialize-st-in-elf_is_symlink.patch
@@ -0,0 +1,32 @@
+From a6c384f38421ed62d5acac30a90dc92de5cf4055 Mon Sep 17 00:00:00 2001
+From: James Hilliard <james.hilliard1@gmail.com>
+Date: Mon, 18 Mar 2019 09:17:39 +0800
+Subject: [PATCH] [libbacktrace] Initialize st in elf_is_symlink
+MIME-Version: 1.0
+Content-Type: text/plain; charset=UTF-8
+Content-Transfer-Encoding: 8bit
+
+Fixes error: ?st.st_mode? may be used uninitialized in this function
+
+Signed-off-by: James Hilliard <james.hilliard1@gmail.com>
+[Upstream status: https://patchwork.ozlabs.org/patch/1057631/]
+---
+ libbacktrace/elf.c | 2 +-
+ 1 file changed, 1 insertion(+), 1 deletion(-)
+
+diff --git a/libbacktrace/elf.c b/libbacktrace/elf.c
+index f4863f0bea5..6cc2a7dec22 100644
+--- a/libbacktrace/elf.c
++++ b/libbacktrace/elf.c
+@@ -765,7 +765,7 @@ elf_syminfo (struct backtrace_state *state, uintptr_t addr,
+ static int
+ elf_is_symlink (const char *filename)
+ {
+-  struct stat st;
++  struct stat st={0};
+ 
+   if (lstat (filename, &st) < 0)
+     return 0;
+-- 
+2.17.1
+
-- 
2.17.1

[Buildroot] [PATCH 1/1] package/gcc: Initialize st in elf_is_symlink

[Thomas Petazzoni]

Hello James,

On Mon, 18 Mar 2019 09:59:33 +0800
james.hilliard1 at gmail.com wrote:

> From: James Hilliard <james.hilliard1@gmail.com>
> 
> Fixes:
> ../../../../libsanitizer/libbacktrace/../../libbacktrace/elf.c: In function ?elf_is_symlink?:
> ../../../../libsanitizer/libbacktrace/../../libbacktrace/elf.c:772:21: error: ?st.st_mode? may be used uninitialized in this function [-Werror=maybe-uninitialized]
>    return S_ISLNK (st.st_mode);
>                      ^
> 
> Signed-off-by: James Hilliard <james.hilliard1@gmail.com>
> ---
>  ...race-Initialize-st-in-elf_is_symlink.patch | 32 +++++++++++++++++++
>  1 file changed, 32 insertions(+)
>  create mode 100644 package/gcc/8.3.0/0001-libbacktrace-Initialize-st-in-elf_is_symlink.patch

The patch has been rejected upstream, so I'm not really keen on merging
this. In addition, you're not giving enough details on the conditions
under which this issue was found. Which configuration ? Which host gcc
version ? etc.

Best regards,

Thomas
-- 
Thomas Petazzoni, CTO, Bootlin
Embedded Linux and Kernel engineering
https://bootlin.com