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| author | Thomas Weißschuh <linux@weissschuh.net> | 2024-05-03 16:44:09 +0300 |
|---|---|---|
| committer | Kees Cook <keescook@chromium.org> | 2024-05-03 22:35:12 +0300 |
| commit | 0e148d3cca0dc1a7c6063939f6cb9ba4866c39a7 (patch) | |
| tree | a2f14853623d0ec84dfca6c5ea7616447c0a708f /kernel/stackleak.c | |
| parent | 7d78a77733552092361239b1d8afaf8412f5dffd (diff) | |
| download | linux-0e148d3cca0dc1a7c6063939f6cb9ba4866c39a7.tar.xz | |
stackleak: Use a copy of the ctl_table argument
Sysctl handlers are not supposed to modify the ctl_table passed to them.
Adapt the logic to work with a temporary variable, similar to how it is
done in other parts of the kernel.
This is also a prerequisite to enforce the immutability of the argument
through the callbacks.
Reviewed-by: Luis Chamberlain <mcgrof@kernel.org>
Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
Reviewed-by: Tycho Andersen <tycho@tycho.pizza>
Link: https://lore.kernel.org/r/20240503-sysctl-const-stackleak-v1-1-603fecb19170@weissschuh.net
Signed-off-by: Kees Cook <keescook@chromium.org>
Diffstat (limited to 'kernel/stackleak.c')
| -rw-r--r-- | kernel/stackleak.c | 6 |
1 files changed, 3 insertions, 3 deletions
diff --git a/kernel/stackleak.c b/kernel/stackleak.c index 34c9d81eea94..59cdfaf5118e 100644 --- a/kernel/stackleak.c +++ b/kernel/stackleak.c @@ -27,10 +27,10 @@ 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 table_copy = *table; - table->data = &state; - table->maxlen = sizeof(int); - ret = proc_dointvec_minmax(table, write, buffer, lenp, ppos); + table_copy.data = &state; + ret = proc_dointvec_minmax(&table_copy, write, buffer, lenp, ppos); state = !!state; if (ret || !write || state == prev_state) return ret; |