| Message ID | 20240918073257.13930-1-liwang@redhat.com |
|---|---|
| State | Accepted |
| Headers | show |
| Series | lib: handle ENOENT errors when processes exit during PID scanning | expand |
Hi!
I've spend some time looking at the code that uses the
FILE_LINES_SCANF() and it looks like this change shouldn't break
anything.
Reviewed-by: Cyril Hrubis <chrubis@suse.cz>
Cyril Hrubis <chrubis@suse.cz> wrote: Hi! > I've spend some time looking at the code that uses the > FILE_LINES_SCANF() and it looks like this change shouldn't break > anything. > > Reviewed-by: Cyril Hrubis <chrubis@suse.cz> > Patch merged, thank you.
diff --git a/lib/safe_file_ops.c b/lib/safe_file_ops.c index 63ae2dbbe..4cf0d6e0f 100644 --- a/lib/safe_file_ops.c +++ b/lib/safe_file_ops.c @@ -182,6 +182,9 @@ int file_lines_scanf(const char *file, const int lineno, fp = fopen(path, "r"); if (fp == NULL) { + if (strict == 0 && errno == ENOENT) + return 1; + tst_brkm_(file, lineno, TBROK | TERRNO, cleanup_fn, "Failed to open FILE '%s' for reading", path); return 1;
There is a race window between readdir() and fopen() in line 125~131 of lib function get_used_pids. A process could terminate after its directory entry is read but before its status file is opened. When fopen() is called, the status file may no longer exist, resulting in an error like: tag=msgstress01__with_dmesg_entry stime=1723563200 ... tst_test.c:1617: TINFO: Timeout per run is 0h 03m 30s tst_pid.c:128: TBROK: Failed to open FILE '/proc/73429/status' for reading: ENOENT (2) To resolve this, the file_lines_scanf() function is modified to handle ENOENT errors gracefully when strict mode is not enabled. If fopen() fails due to ENOENT, the function now returns 1 to skip the missing file instead of treating it as a critical error. Reported-by: Paul Bunyan <pbunyan@redhat.com> Analysed-by: Charles Mirabile <cmirabil@redhat.com> Signed-off-by: Li Wang <liwang@redhat.com> --- lib/safe_file_ops.c | 3 +++ 1 file changed, 3 insertions(+)