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| author | Tobin C. Harding <me@tobin.cc> | 2018-02-27 15:02:57 +1100 |
|---|---|---|
| committer | Tobin C. Harding <me@tobin.cc> | 2018-04-07 08:50:34 +1000 |
| commit | 472c9e1085f20de71fc482500c8f1e4e45dff651 (patch) | |
| tree | b710800c2d94e77eaae3c728449f1d4643b65096 /scripts/leaking_addresses.pl | |
| parent | 5e4bac34edc7829b4a0749e3870d4a171c1f036f (diff) | |
| download | lwn-472c9e1085f20de71fc482500c8f1e4e45dff651.tar.gz lwn-472c9e1085f20de71fc482500c8f1e4e45dff651.zip | |
leaking_addresses: skip all /proc/PID except /proc/1
When the system is idle it is likely that most files under /proc/PID
will be identical for various processes. Scanning _all_ the PIDs under
/proc is unnecessary and implies that we are thoroughly scanning /proc.
This is _not_ the case because there may be ways userspace can trigger
creation of /proc files that leak addresses but were not present during
a scan. For these two reasons we should exclude all PID directories
under /proc except '1/'
Exclude all /proc/PID except /proc/1.
Signed-off-by: Tobin C. Harding <me@tobin.cc>
Diffstat (limited to 'scripts/leaking_addresses.pl')
| -rwxr-xr-x | scripts/leaking_addresses.pl | 12 |
1 files changed, 12 insertions, 0 deletions
diff --git a/scripts/leaking_addresses.pl b/scripts/leaking_addresses.pl index 6e5bc57caeaa..2075d98278f2 100755 --- a/scripts/leaking_addresses.pl +++ b/scripts/leaking_addresses.pl @@ -10,6 +10,14 @@ # Use --debug to output path before parsing, this is useful to find files that # cause the script to choke. +# +# When the system is idle it is likely that most files under /proc/PID will be +# identical for various processes. Scanning _all_ the PIDs under /proc is +# unnecessary and implies that we are thoroughly scanning /proc. This is _not_ +# the case because there may be ways userspace can trigger creation of /proc +# files that leak addresses but were not present during a scan. For these two +# reasons we exclude all PID directories under /proc except '1/' + use warnings; use strict; use POSIX; @@ -472,6 +480,10 @@ sub walk my $path = "$pwd/$file"; next if (-l $path); + # skip /proc/PID except /proc/1 + next if (($path =~ /^\/proc\/[0-9]+$/) && + ($path !~ /^\/proc\/1$/)); + next if (skip($path)); if (-d $path) { |