Use of uninitialized value $sdev in right bitshift

[heapdavid]

Hi, we run needrestart -b on a cron and occasionally see the following output to stderr on some of our busier servers. We're struggling to reproduce reliably as it's pretty rare and intermittent.

Use of uninitialized value $sdev in right bitshift (>>) at /usr/sbin/needrestart line 532, <HMAP> line 2.
Use of uninitialized value $sdev in right bitshift (>>) at /usr/sbin/needrestart line 532, <HMAP> line 2.
Use of uninitialized value $sdev in bitwise and (&) at /usr/sbin/needrestart line 532, <HMAP> line 2.
Use of uninitialized value $sdev in right bitshift (>>) at /usr/sbin/needrestart line 532, <HMAP> line 2.
Use of uninitialized value $sdev in right bitshift (>>) at /usr/sbin/needrestart line 532, <HMAP> line 2.
Use of uninitialized value $sdev in bitwise and (&) at /usr/sbin/needrestart line 532, <HMAP> line 2.
Use of uninitialized value $sdev in right bitshift (>>) at /usr/sbin/needrestart line 544, <HMAP> line 2.
Use of uninitialized value $sdev in right bitshift (>>) at /usr/sbin/needrestart line 544, <HMAP> line 2.
Use of uninitialized value $sinode in string eq at /usr/sbin/needrestart line 549, <HMAP> line 2

Have seen there was a similar issue a while ago but that looked to be fixed at the time.

We're running Debian 12 (Bookworm)

$ apt list needrestart
Listing... Done
needrestart/stable,now 3.6-4 all [installed]

Please let me know if you need any further information

Thanks

[liske]

Needrestart tries to compares the inode information from /proc/$PID/maps with the corresponding files in the filesystem. For some reasons the stat call seems to fail for some reasons:

needrestart/needrestart

Line 555 in c62b152

my ($sdev, $sinode) = stat($testp);

The path is the first available: at

needrestart/needrestart

Lines 543 to 544 in c62b152

	my @paths = ("/proc/$pid/map_files/$maddr", "/proc/$pid/root/$path");
	my ($testp) = grep { -e $_; } @paths;

Do you have any special filesystem setup? This might also happen if the process terminates while needrestart is investigating the procfs. 🤔