This is the mail archive of the
elfutils-devel@sourceware.org
mailing list for the elfutils project.
[PATCH] libdwfl: Fix some GCC10 -Wnull-dereference issues.
- From: Mark Wielaard <mark at klomp dot org>
- To: elfutils-devel at sourceware dot org
- Cc: Mark Wielaard <mark at klomp dot org>
- Date: Fri, 24 Jan 2020 23:28:21 +0100
- Subject: [PATCH] libdwfl: Fix some GCC10 -Wnull-dereference issues.
GCC10 on some arches will warn about possible NULL derefences.
In the libdwfl linux-kernel-modules.c cases it might be caught already
by earlier calls to get_release (). But it is hard to see that will
really always happen. So do an explicit NULL check just in case.
Signed-off-by: Mark Wielaard <mark@klomp.org>
---
libdwfl/ChangeLog | 6 ++++++
libdwfl/linux-kernel-modules.c | 13 ++++++++++---
2 files changed, 16 insertions(+), 3 deletions(-)
diff --git a/libdwfl/ChangeLog b/libdwfl/ChangeLog
index b36a7ca6..0b95490a 100644
--- a/libdwfl/ChangeLog
+++ b/libdwfl/ChangeLog
@@ -1,3 +1,9 @@
+2020-01-24 Mark Wielaard <mark@klomp.org>
+
+ * linux-kernel-modules.c (find_kernel_elf): Check release isn't NULL.
+ (report_kernel): Check release and *release aren't NULL.
+ (report_kernel_archive): Likewise.
+
2019-12-11 Omar Sandoval <osandov@fb.com>
* libdwflP.h (Dwfl_Module): Remove coalescing state.
diff --git a/libdwfl/linux-kernel-modules.c b/libdwfl/linux-kernel-modules.c
index 48fb1ff0..0434f1e5 100644
--- a/libdwfl/linux-kernel-modules.c
+++ b/libdwfl/linux-kernel-modules.c
@@ -176,9 +176,10 @@ find_kernel_elf (Dwfl *dwfl, const char *release, char **fname)
{
/* First try to find an uncompressed vmlinux image. Possibly
including debuginfo. */
- if ((release[0] == '/'
- ? asprintf (fname, "%s/vmlinux", release)
- : asprintf (fname, "/boot/vmlinux-%s", release)) < 0)
+ if (release == NULL
+ || ((release[0] == '/'
+ ? asprintf (fname, "%s/vmlinux", release)
+ : asprintf (fname, "/boot/vmlinux-%s", release)) < 0))
return -1;
int fd = try_kernel_name (dwfl, fname, true);
@@ -241,6 +242,9 @@ report_kernel (Dwfl *dwfl, const char **release,
if (unlikely (result != 0))
return result;
+ if (release == NULL || *release == NULL)
+ return EINVAL;
+
char *fname;
int fd = find_kernel_elf (dwfl, *release, &fname);
@@ -296,6 +300,9 @@ report_kernel_archive (Dwfl *dwfl, const char **release,
if (unlikely (result != 0))
return result;
+ if (release == NULL || *release == NULL)
+ return EINVAL;
+
char *archive;
int res = (((*release)[0] == '/')
? asprintf (&archive, "%s/debug.a", *release)
--
2.18.1