diff options
author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-27 10:05:51 +0000 |
---|---|---|
committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-27 10:05:51 +0000 |
commit | 5d1646d90e1f2cceb9f0828f4b28318cd0ec7744 (patch) | |
tree | a94efe259b9009378be6d90eb30d2b019d95c194 /tools/testing/selftests/bpf/progs/dev_cgroup.c | |
parent | Initial commit. (diff) | |
download | linux-upstream.tar.xz linux-upstream.zip |
Adding upstream version 5.10.209.upstream/5.10.209upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'tools/testing/selftests/bpf/progs/dev_cgroup.c')
-rw-r--r-- | tools/testing/selftests/bpf/progs/dev_cgroup.c | 60 |
1 files changed, 60 insertions, 0 deletions
diff --git a/tools/testing/selftests/bpf/progs/dev_cgroup.c b/tools/testing/selftests/bpf/progs/dev_cgroup.c new file mode 100644 index 000000000..8924e06bd --- /dev/null +++ b/tools/testing/selftests/bpf/progs/dev_cgroup.c @@ -0,0 +1,60 @@ +/* Copyright (c) 2017 Facebook + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of version 2 of the GNU General Public + * License as published by the Free Software Foundation. + */ + +#include <linux/bpf.h> +#include <linux/version.h> +#include <bpf/bpf_helpers.h> + +SEC("cgroup/dev") +int bpf_prog1(struct bpf_cgroup_dev_ctx *ctx) +{ + short type = ctx->access_type & 0xFFFF; +#ifdef DEBUG + short access = ctx->access_type >> 16; + char fmt[] = " %d:%d \n"; + + switch (type) { + case BPF_DEVCG_DEV_BLOCK: + fmt[0] = 'b'; + break; + case BPF_DEVCG_DEV_CHAR: + fmt[0] = 'c'; + break; + default: + fmt[0] = '?'; + break; + } + + if (access & BPF_DEVCG_ACC_READ) + fmt[8] = 'r'; + + if (access & BPF_DEVCG_ACC_WRITE) + fmt[9] = 'w'; + + if (access & BPF_DEVCG_ACC_MKNOD) + fmt[10] = 'm'; + + bpf_trace_printk(fmt, sizeof(fmt), ctx->major, ctx->minor); +#endif + + /* Allow access to /dev/zero and /dev/random. + * Forbid everything else. + */ + if (ctx->major != 1 || type != BPF_DEVCG_DEV_CHAR) + return 0; + + switch (ctx->minor) { + case 5: /* 1:5 /dev/zero */ + case 9: /* 1:9 /dev/urandom */ + return 1; + } + + return 0; +} + +char _license[] SEC("license") = "GPL"; +__u32 _version SEC("version") = LINUX_VERSION_CODE; |