[PATCH] libdwfl: Make sure there is at least one phdr

[Mark Wielaard]

The buffer read in needs to contain room for at least one Phdr.

Signed-off-by: Mark Wielaard <m...@klomp.org>
---
 libdwfl/ChangeLog  | 4 ++++
 libdwfl/link_map.c | 5 +++++
 2 files changed, 9 insertions(+)

diff --git a/libdwfl/ChangeLog b/libdwfl/ChangeLog
index d4eee639..8760b1ef 100644
--- a/libdwfl/ChangeLog
+++ b/libdwfl/ChangeLog
@@ -1,3 +1,7 @@
+2021-12-16  Mark Wielaard  <m...@klomp.org>
+
+       * link_map.c (dwfl_link_map_report): Make sure phnum is non-zero.
+
 2021-12-16  Mark Wielaard  <m...@klomp.org>
 
        * link_map.c (dwfl_link_map_report): Make sure dyn_filesz / entsize is
diff --git a/libdwfl/link_map.c b/libdwfl/link_map.c
index 177ad9a5..c4f79f11 100644
--- a/libdwfl/link_map.c
+++ b/libdwfl/link_map.c
@@ -890,6 +890,11 @@ dwfl_link_map_report (Dwfl *dwfl, const void *auxv, size_t 
auxv_size,
                {
                  nbytes = in.d_size;
                  phnum = nbytes / phent;
+                 if (phnum == 0)
+                   {
+                     __libdwfl_seterrno (DWFL_E_BADELF);
+                     return false;
+                   }
                }
              void *buf = malloc (nbytes);
              Elf32_Phdr (*p32)[phnum] = buf;
-- 
2.30.2