[PATCH 01/11] stackleak: don't modify ctl_table argument
From: Thomas Weißschuh <linux@weissschuh.net>
Date: 2024-03-15 20:48:25
Also in:
bpf, bridge, kexec, linux-fsdevel, linux-hardening, linux-mm, linux-nfs, linux-perf-users, linux-rdma, linux-riscv, linux-s390, linux-sctp, linux-security-module, linux-trace-kernel, linux-xfs, lkml, lvs-devel, netdev, netfilter-devel
Subsystem:
the rest · Maintainer:
Linus Torvalds
In a future commit the proc_handlers will change to
"const struct ctl_table".
As a preparation for that adapt the logic to work with a temporary
variable, similar to how it is done in other parts of the kernel.
Fixes: 964c9dff0091 ("stackleak: Allow runtime disabling of kernel stack erasing")
Acked-by: Kees Cook <redacted>
Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
---
kernel/stackleak.c | 7 ++++---
1 file changed, 4 insertions(+), 3 deletions(-)
diff --git a/kernel/stackleak.c b/kernel/stackleak.c
index 34c9d81eea94..b292e5ca0b7d 100644
--- a/kernel/stackleak.c
+++ b/kernel/stackleak.c@@ -27,10 +27,11 @@ static int stack_erasing_sysctl(struct ctl_table *table, int write, int ret = 0; int state = !static_branch_unlikely(&stack_erasing_bypass); int prev_state = state; + struct ctl_table tmp = *table; - table->data = &state; - table->maxlen = sizeof(int); - ret = proc_dointvec_minmax(table, write, buffer, lenp, ppos); + tmp.data = &state; + tmp.maxlen = sizeof(int); + ret = proc_dointvec_minmax(&tmp, write, buffer, lenp, ppos); state = !!state; if (ret || !write || state == prev_state) return ret;
--
2.44.0