Signed-off-by: Luca Guerra <luca@guerra.sh>
Co-authored-by: Jason Dellaluce <jasondellaluce@gmail.com>
Co-authored-by: Jason Dellaluce <jasondellaluce@gmail.com>
Note that another bump is required before releasing Falco, since this commit uses alpha versions.
Signed-off-by: Leonardo Grasso <me@leonardograsso.com>
Perform the validate_rules action before the load_rules action. This
ensures that *only* the rules files named with -V arguments are
validated.
This fixes https://github.com/falcosecurity/falco/issues/2087.
Signed-off-by: Mark Stemm <mark.stemm@gmail.com>
In some cases the rule is not triggered when a reverse shell is spawned.
That's because in the rule we are checking that the file descriptor passed
as argument to the dup functions is of type socket and its fd number is "0, 1, or 2"
and the event direction is "enter".
The following event does not trigger the rule: dup2(socket_fd, STDIN_FILENO);
But using the exit event the rule is triggered.
Signed-off-by: Aldo Lacuku <aldo@lacuku.eu>
The Flatcar kernel module build needs to relocate binaries in /host/lib/modules
to run with the host's ld and glibc. While testing with glibc 2.34 that we plan
to introduce soon, we found that the previous dynlinker symlink (ld-xxx.so)
doesn't exist any longer. Update the hostld variable to use a path that is
present in all versions of glibc.
Signed-off-by: Jeremi Piotrowski <jpiotrowski@microsoft.com>
Pre-built kernel modules/eBPF probes for Flatcar use the value of the OS
VERSION_ID field as KERNEL_RELEASE in the filename. A specific kernel release
version does not uniquely identify a Flatcar configuration, because Flatcar is
image-based instead of package-based. Here's a more specific example: the same
kernel version can be part of various Flatcar releases (across channels
alpha/beta/stable) with differences in configuration. This is why we use the
VERSION_ID value during offline builds with driverkit. Flatcar version numbers
are all higher than 1500.0.0, so there is no risk of collision with kernel
version numbers.
When locally building the kernel module on the system, we have access to the
correct kernel build directory at /lib/modules/$(uname -r)/build with the right
configuration and so for that branch, we need to reset KERNEL_RELEASE=$(uname -r).
See also the driverkit PR that introduces a builder for Flatcar:
https://github.com/falcosecurity/driverkit/pull/131
Signed-off-by: Jeremi Piotrowski <jpiotrowski@microsoft.com>
Relocate necessary tools from the kernel module build system to run using host
dynlinker and libraries, so that compiling falco module on Flatcar works.
Since Flatcar v2983.0.0, Flatcar ships with glibc-2.33, but the
falco-driver-loader container is based on debian:buster and so has a much older
glibc. This prevents some necessary tools within /lib/modules/*/build from
working which causes the falco module to fail to compile using dkms.
To make the tools work, we need to relocate them so we add patchelf to the
falco and local dockerfiles. The relocation is based on the approach done by
the sysdig agent-kmodule build system, but I'm unable to find the source code
for it. The host linker and libs will be found at /host/usr/lib64, so we change
the interpreter and rpath on the tools. The relocation happens on a copy of the
tools which are then bind mounted at the right location. The result allows the
module build to work.
Signed-off-by: Jeremi Piotrowski <jpiotrowski@microsoft.com>
