Allow bpf() syscall
The implementation of FUSE BPF requires the FUSE daemon to access BPF
functionalities, i.e., to get the fd of a pinned BPF prog and to update
maps.
In Android the FUSE daemon is part of MediaProvider which, belonging to
the apps domain, can only access the subset of syscalls allowed by
seccomp, of which bpf() is currently blocked.
This patch removes this limitation by adding the bpf() syscall to the
allowed seccomp syscalls.
Allowing the bpf() syscall is safe as its usage is still gated by
selinux and regular apps are not allowed to use it.
Bug: 202785178
Test: m
Signed-off-by: Alessio Balsini <balsini@google.com>
Change-Id: I5887e8d22906c386307e54d3131c679fee0d9f26
diff --git a/libc/SYSCALLS.TXT b/libc/SYSCALLS.TXT
index 22b82f1..a09c614 100644
--- a/libc/SYSCALLS.TXT
+++ b/libc/SYSCALLS.TXT
@@ -306,6 +306,8 @@
int sysinfo(struct sysinfo*) all
int personality(unsigned long) all
+int bpf(int, union bpf_attr *, unsigned int) all
+
ssize_t tee(int, int, size_t, unsigned int) all
ssize_t splice(int, off64_t*, int, off64_t*, size_t, unsigned int) all
ssize_t vmsplice(int, const struct iovec*, size_t, unsigned int) all