| Message ID | 20230922175229.work.838-kees@kernel.org (mailing list archive) |
|---|---|
| State | Mainlined |
| Commit | fed2ef7abaebe5e0207cd52ae52721ea3da3b5ba |
| Headers | show |
| Series | reset: Annotate struct reset_control_array with __counted_by | expand |
On 9/22/23 11:52, Kees Cook wrote: > Prepare for the coming implementation by GCC and Clang of the __counted_by > attribute. Flexible array members annotated with __counted_by can have > their accesses bounds-checked at run-time checking via CONFIG_UBSAN_BOUNDS > (for array indexing) and CONFIG_FORTIFY_SOURCE (for strcpy/memcpy-family > functions). > > As found with Coccinelle[1], add __counted_by for struct reset_control_array. > Additionally, since the element count member must be set before accessing > the annotated flexible array member, move its initialization earlier. > > [1] https://github.com/kees/kernel-tools/blob/trunk/coccinelle/examples/counted_by.cocci > > Cc: Philipp Zabel <p.zabel@pengutronix.de> > Signed-off-by: Kees Cook <keescook@chromium.org> Reviewed-by: Gustavo A. R. Silva <gustavoars@kernel.org> Thanks
On Fri, 22 Sep 2023 10:52:29 -0700, Kees Cook wrote: > Prepare for the coming implementation by GCC and Clang of the __counted_by > attribute. Flexible array members annotated with __counted_by can have > their accesses bounds-checked at run-time checking via CONFIG_UBSAN_BOUNDS > (for array indexing) and CONFIG_FORTIFY_SOURCE (for strcpy/memcpy-family > functions). > > As found with Coccinelle[1], add __counted_by for struct reset_control_array. > Additionally, since the element count member must be set before accessing > the annotated flexible array member, move its initialization earlier. > > [...] Applied to for-next/hardening, thanks! [1/1] reset: Annotate struct reset_control_array with __counted_by https://git.kernel.org/kees/c/fed2ef7abaeb Take care,
diff --git a/drivers/reset/core.c b/drivers/reset/core.c index f0a076e94118..7ece6a8e9858 100644 --- a/drivers/reset/core.c +++ b/drivers/reset/core.c @@ -60,7 +60,7 @@ struct reset_control { struct reset_control_array { struct reset_control base; unsigned int num_rstcs; - struct reset_control *rstc[]; + struct reset_control *rstc[] __counted_by(num_rstcs); }; static const char *rcdev_name(struct reset_controller_dev *rcdev) @@ -1185,6 +1185,7 @@ of_reset_control_array_get(struct device_node *np, bool shared, bool optional, resets = kzalloc(struct_size(resets, rstc, num), GFP_KERNEL); if (!resets) return ERR_PTR(-ENOMEM); + resets->num_rstcs = num; for (i = 0; i < num; i++) { rstc = __of_reset_control_get(np, NULL, i, shared, optional, @@ -1193,7 +1194,6 @@ of_reset_control_array_get(struct device_node *np, bool shared, bool optional, goto err_rst; resets->rstc[i] = rstc; } - resets->num_rstcs = num; resets->base.array = true; return &resets->base;
Prepare for the coming implementation by GCC and Clang of the __counted_by attribute. Flexible array members annotated with __counted_by can have their accesses bounds-checked at run-time checking via CONFIG_UBSAN_BOUNDS (for array indexing) and CONFIG_FORTIFY_SOURCE (for strcpy/memcpy-family functions). As found with Coccinelle[1], add __counted_by for struct reset_control_array. Additionally, since the element count member must be set before accessing the annotated flexible array member, move its initialization earlier. [1] https://github.com/kees/kernel-tools/blob/trunk/coccinelle/examples/counted_by.cocci Cc: Philipp Zabel <p.zabel@pengutronix.de> Signed-off-by: Kees Cook <keescook@chromium.org> --- drivers/reset/core.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)