This is a note to let you know that I've just added the patch titled
net, sysctl: Fix compiler warning when only cBPF is present
to the 4.19-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
net-sysctl-fix-compiler-warning-when-only-cbpf-is-pr.patch
and it can be found in the queue-4.19 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit 57a72b38fe594c1d0545eacb029097f23b342b08
Author: Alexander Lobakin <alobakin@xxxxxxxx>
Date: Wed Dec 18 12:18:21 2019 +0300
net, sysctl: Fix compiler warning when only cBPF is present
[ Upstream commit 1148f9adbe71415836a18a36c1b4ece999ab0973 ]
proc_dointvec_minmax_bpf_restricted() has been firstly introduced
in commit 2e4a30983b0f ("bpf: restrict access to core bpf sysctls")
under CONFIG_HAVE_EBPF_JIT. Then, this ifdef has been removed in
ede95a63b5e8 ("bpf: add bpf_jit_limit knob to restrict unpriv
allocations"), because a new sysctl, bpf_jit_limit, made use of it.
Finally, this parameter has become long instead of integer with
fdadd04931c2 ("bpf: fix bpf_jit_limit knob for PAGE_SIZE >= 64K")
and thus, a new proc_dolongvec_minmax_bpf_restricted() has been
added.
With this last change, we got back to that
proc_dointvec_minmax_bpf_restricted() is used only under
CONFIG_HAVE_EBPF_JIT, but the corresponding ifdef has not been
brought back.
So, in configurations like CONFIG_BPF_JIT=y && CONFIG_HAVE_EBPF_JIT=n
since v4.20 we have:
CC net/core/sysctl_net_core.o
net/core/sysctl_net_core.c:292:1: warning: â??proc_dointvec_minmax_bpf_restrictedâ?? defined but not used [-Wunused-function]
292 | proc_dointvec_minmax_bpf_restricted(struct ctl_table *table, int write,
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Suppress this by guarding it with CONFIG_HAVE_EBPF_JIT again.
Fixes: fdadd04931c2 ("bpf: fix bpf_jit_limit knob for PAGE_SIZE >= 64K")
Signed-off-by: Alexander Lobakin <alobakin@xxxxxxxx>
Signed-off-by: Daniel Borkmann <daniel@xxxxxxxxxxxxx>
Link: https://lore.kernel.org/bpf/20191218091821.7080-1-alobakin@xxxxxxxx
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/net/core/sysctl_net_core.c b/net/core/sysctl_net_core.c
index d67ec17f2cc8..6cec08cd0bb9 100644
--- a/net/core/sysctl_net_core.c
+++ b/net/core/sysctl_net_core.c
@@ -281,6 +281,7 @@ static int proc_dointvec_minmax_bpf_enable(struct ctl_table *table, int write,
return ret;
}
+# ifdef CONFIG_HAVE_EBPF_JIT
static int
proc_dointvec_minmax_bpf_restricted(struct ctl_table *table, int write,
void __user *buffer, size_t *lenp,
@@ -291,6 +292,7 @@ proc_dointvec_minmax_bpf_restricted(struct ctl_table *table, int write,
return proc_dointvec_minmax(table, write, buffer, lenp, ppos);
}
+# endif /* CONFIG_HAVE_EBPF_JIT */
static int
proc_dolongvec_minmax_bpf_restricted(struct ctl_table *table, int write,
