Youlin Li f1db20814a bpf: Fix wrong reg type conversion in release_reference()
Some helper functions will allocate memory. To avoid memory leaks, the
verifier requires the eBPF program to release these memories by calling
the corresponding helper functions.

When a resource is released, all pointer registers corresponding to the
resource should be invalidated. The verifier use release_references() to
do this job, by apply  __mark_reg_unknown() to each relevant register.

It will give these registers the type of SCALAR_VALUE. A register that
will contain a pointer value at runtime, but of type SCALAR_VALUE, which
may allow the unprivileged user to get a kernel pointer by storing this
register into a map.

Using __mark_reg_not_init() while NOT allow_ptr_leaks can mitigate this
problem.

Fixes: fd978bf7fd31 ("bpf: Add reference tracking to verifier")
Signed-off-by: Youlin Li <liulin063@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20221103093440.3161-1-liulin063@gmail.com
2022-11-04 00:24:12 +01:00
..
2022-10-17 18:52:43 -07:00
2022-09-28 09:02:20 +02:00
2022-09-26 19:46:18 -07:00
2022-10-17 16:32:05 +02:00
2022-10-10 11:36:19 -07:00
2022-10-10 09:10:28 -07:00
2022-08-29 19:47:03 -04:00
2022-10-04 11:05:43 -07:00
2022-09-26 10:13:13 -07:00
2022-05-23 17:51:12 -07:00
2022-10-03 17:11:07 -07:00
2022-09-01 16:55:35 +02:00
2022-06-29 13:07:16 +02:00
2022-10-10 09:10:28 -07:00
2022-10-10 12:49:34 -07:00
2022-08-06 16:38:17 -07:00
2022-10-03 17:11:07 -07:00