msan detects uninitialized variables in tar1.34

[2773414454]

Hello.

Enable the msan compilation option and compile the tar1.34 in clang.(https://clang.llvm.org/docs/MemorySanitizer.html)

msan detects uninitialized variables in tar1.34

#/home/tar-1.34/src/tar -cf /home/new.tar /home/lost+found/
/home/tar-1.34/src/tar: Removing leading ??/' from member names
==832799==MemorySanitizer: use-of-uninitialized-value
#0 0x4d3411 (/home/tar-1.34/src/tar+0x4d3411)
#1 Ox4cdfb7 (/home/tar-1.34/src/tar+0x4cdfb7)
#2 0x54bbb7  (/home/tar-1.34/src/tar+0x54bbb7)
#3 Ox7ff1320ab20f (/usr/1ib64/libc.so.6+0x2d20f)
#4 Ox7ff1320ab2bb = (/usr/1ib64/libc.so.6+0x2d2bb)
#5 0x42b9a4  (/home/tar-1.34/src/tar+0x42b9a4)
Uninitialized value was created by an allocation of ??final_stat' in the stack frame of function ??dump filed"
#0 0x4cee90  (/home/tar-1.34/src/tar+0x4cee90)
SUMMARY: MemorySanitizer: use-of-uninitialized-value (/home/tar-1.34/src/tar+0x4d3411)

Exiting

After initialization is added to the stbuf structure, recompile the stbuf structure and run the test. The corresponding MSAN alarm is cleared.

 src/system.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/src/system.c b/src/system.c
index 2988ed08..76db1f38 100644
--- a/src/system.c
+++ b/src/system.c
@@ -283,6 +283,7 @@ static int
 is_regular_file (const char *name)
 {
   struct stat stbuf;
+  memset(&stbuf,0,sizeof(struct stat));
 
   if (stat (name, &stbuf) == 0)
     return S_ISREG (stbuf.st_mode);

---

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0001-Initializing-variable-struct-stat-stbuf-memory.patch.txt
Description: Binary data