The elf_create_file() function fails with EINVAL when the build directory
path is long enough to truncate the "XXXXXX" suffix in the 256-byte
tmp_name buffer.

Simplify the code to remove the unnecessary dirname()/basename() split
and concatenation.  Instead, allocate the exact number of bytes needed for
the path.

Signed-off-by: Joe Lawrence <[email protected]>
---
 tools/objtool/elf.c | 23 +++--------------------
 1 file changed, 3 insertions(+), 20 deletions(-)

diff --git a/tools/objtool/elf.c b/tools/objtool/elf.c
index bd6502e7bdc0..6f6d1c4cb6af 100644
--- a/tools/objtool/elf.c
+++ b/tools/objtool/elf.c
@@ -16,7 +16,6 @@
 #include <string.h>
 #include <unistd.h>
 #include <errno.h>
-#include <libgen.h>
 #include <ctype.h>
 #include <linux/align.h>
 #include <linux/kernel.h>
@@ -1189,7 +1188,7 @@ struct elf *elf_open_read(const char *name, int flags)
 struct elf *elf_create_file(GElf_Ehdr *ehdr, const char *name)
 {
        struct section *null, *symtab, *strtab, *shstrtab;
-       char *dir, *base, *tmp_name;
+       char *tmp_name;
        struct symbol *sym;
        struct elf *elf;
 
@@ -1203,29 +1202,13 @@ struct elf *elf_create_file(GElf_Ehdr *ehdr, const char 
*name)
 
        INIT_LIST_HEAD(&elf->sections);
 
-       dir = strdup(name);
-       if (!dir) {
-               ERROR_GLIBC("strdup");
-               return NULL;
-       }
-
-       dir = dirname(dir);
-
-       base = strdup(name);
-       if (!base) {
-               ERROR_GLIBC("strdup");
-               return NULL;
-       }
-
-       base = basename(base);
-
-       tmp_name = malloc(256);
+       tmp_name = malloc(strlen(name) + 8);
        if (!tmp_name) {
                ERROR_GLIBC("malloc");
                return NULL;
        }
 
-       snprintf(tmp_name, 256, "%s/%s.XXXXXX", dir, base);
+       sprintf(tmp_name, "%s.XXXXXX", name);
 
        elf->fd = mkstemp(tmp_name);
        if (elf->fd == -1) {
-- 
2.53.0


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