| Message ID | 30306253b1b5e6b8f5c0faba97e935eda4638020.1645583264.git.gustavoars@kernel.org |
|---|---|
| State | New |
| Headers | show |
| Series | ath6kl: wmi: Replace one-element arrays with flexible-array members | expand |
diff --git a/drivers/net/wireless/ath/ath6kl/wmi.c b/drivers/net/wireless/ath/ath6kl/wmi.c index bdfc057c5a82..049d75f31f3c 100644 --- a/drivers/net/wireless/ath/ath6kl/wmi.c +++ b/drivers/net/wireless/ath/ath6kl/wmi.c @@ -1240,7 +1240,7 @@ static int ath6kl_wmi_ratemask_reply_rx(struct wmi *wmi, u8 *datap, int len) static int ath6kl_wmi_ch_list_reply_rx(struct wmi *wmi, u8 *datap, int len) { - if (len < sizeof(struct wmi_channel_list_reply)) + if (len <= sizeof(struct wmi_channel_list_reply)) return -EINVAL; ath6kl_wakeup_event(wmi->parent_dev); diff --git a/drivers/net/wireless/ath/ath6kl/wmi.h b/drivers/net/wireless/ath/ath6kl/wmi.h index 9e168752bec2..432e4f428a4a 100644 --- a/drivers/net/wireless/ath/ath6kl/wmi.h +++ b/drivers/net/wireless/ath/ath6kl/wmi.h @@ -1373,7 +1373,7 @@ struct wmi_channel_list_reply { u8 num_ch; /* channel in Mhz */ - __le16 ch_list[1]; + __le16 ch_list[]; } __packed; /* List of Events (target to host) */
Replace one-element array with flexible-array member in struct wmi_channel_list_reply. It's also worth noting that due to the flexible array transformation, the size of struct wmi_channel_list_reply changed, see below. Before flex-array transformation: struct wmi_channel_list_reply { u8 reserved; /* 0 1 */ u8 num_ch; /* 1 1 */ __le16 ch_list[1]; /* 2 2 */ /* size: 4, cachelines: 1, members: 3 */ /* last cacheline: 4 bytes */ }; After flex-array transformation: struct wmi_channel_list_reply { u8 reserved; /* 0 1 */ u8 num_ch; /* 1 1 */ __le16 ch_list[]; /* 2 0 */ /* size: 2, cachelines: 1, members: 3 */ /* last cacheline: 2 bytes */ }; So, the following change preserves the logic that if _len_ is at least 4 bytes in size, this is the existence of at least one channel in ch_list[] is being considered, then the execution jumps to call ath6kl_wakeup_event(wmi->parent_dev);, otherwise _len_ is 2 bytes or less and the code returns -EINVAL: - if (len < sizeof(struct wmi_channel_list_reply)) + if (len <= sizeof(struct wmi_channel_list_reply)) This issue was found with the help of Coccinelle and audited and fixed, manually. Link: https://www.kernel.org/doc/html/v5.16/process/deprecated.html#zero-length-and-one-element-arrays Link: https://github.com/KSPP/linux/issues/79 Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org> --- Hi! It'd be great if someone can confirm or comment on the following changes described in the changelog text: - if (len < sizeof(struct wmi_channel_list_reply)) + if (len <= sizeof(struct wmi_channel_list_reply)) Thanks drivers/net/wireless/ath/ath6kl/wmi.c | 2 +- drivers/net/wireless/ath/ath6kl/wmi.h | 2 +- 2 files changed, 2 insertions(+), 2 deletions(-)