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| author | Gustavo A. R. Silva <gustavoars@kernel.org> | 2024-04-27 01:52:46 +0300 |
|---|---|---|
| committer | Luiz Augusto von Dentz <luiz.von.dentz@intel.com> | 2024-05-14 17:51:06 +0300 |
| commit | c4585edf708edb5277a3cc4b8581ccb833f3307d (patch) | |
| tree | 7aa587f30731a24dd0ca67c80941702ebbe349da /include | |
| parent | 3487cda2742f1c4e404b6c4d5ce1c86f8c661b5c (diff) | |
| download | linux-c4585edf708edb5277a3cc4b8581ccb833f3307d.tar.xz | |
Bluetooth: hci_conn, hci_sync: Use __counted_by() to avoid -Wfamnae warnings
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
via CONFIG_UBSAN_BOUNDS (for array indexing) and CONFIG_FORTIFY_SOURCE
(for strcpy/memcpy-family functions).
Also, -Wflex-array-member-not-at-end is coming in GCC-14, and we are
getting ready to enable it globally.
So, use the `DEFINE_FLEX()` helper for multiple on-stack definitions
of a flexible structure where the size of the flexible-array member
is known at compile-time, and refactor the rest of the code,
accordingly.
Notice that, due to the use of `__counted_by()` in `struct
hci_cp_le_create_cis`, the for loop in function `hci_cs_le_create_cis()`
had to be modified. Once the index `i`, through which `cp->cis[i]` is
accessed, falls in the interval [0, cp->num_cis), `cp->num_cis` cannot
be decremented all the way down to zero while accessing `cp->cis[]`:
net/bluetooth/hci_event.c:4310:
4310 for (i = 0; cp->num_cis; cp->num_cis--, i++) {
...
4314 handle = __le16_to_cpu(cp->cis[i].cis_handle);
otherwise, only half (one iteration before `cp->num_cis == i`) or half
plus one (one iteration before `cp->num_cis < i`) of the items in the
array will be accessed before running into an out-of-bounds issue. So,
in order to avoid this, set `cp->num_cis` to zero just after the for
loop.
Also, make use of `aux_num_cis` variable to update `cmd->num_cis` after
a `list_for_each_entry_rcu()` loop.
With these changes, fix the following warnings:
net/bluetooth/hci_sync.c:1239:56: warning: structure containing a flexible
array member is not at the end of another structure
[-Wflex-array-member-not-at-end]
net/bluetooth/hci_sync.c:1415:51: warning: structure containing a flexible
array member is not at the end of another structure
[-Wflex-array-member-not-at-end]
net/bluetooth/hci_sync.c:1731:51: warning: structure containing a flexible
array member is not at the end of another structure
[-Wflex-array-member-not-at-end]
net/bluetooth/hci_sync.c:6497:45: warning: structure containing a flexible
array member is not at the end of another structure
[-Wflex-array-member-not-at-end]
Link: https://github.com/KSPP/linux/issues/202
Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
Diffstat (limited to 'include')
| -rw-r--r-- | include/net/bluetooth/hci.h | 8 |
1 files changed, 4 insertions, 4 deletions
diff --git a/include/net/bluetooth/hci.h b/include/net/bluetooth/hci.h index 5c12761cbc0e..0b0ac7f06570 100644 --- a/include/net/bluetooth/hci.h +++ b/include/net/bluetooth/hci.h @@ -2026,7 +2026,7 @@ struct hci_cp_le_set_ext_adv_data { __u8 operation; __u8 frag_pref; __u8 length; - __u8 data[]; + __u8 data[] __counted_by(length); } __packed; #define HCI_OP_LE_SET_EXT_SCAN_RSP_DATA 0x2038 @@ -2035,7 +2035,7 @@ struct hci_cp_le_set_ext_scan_rsp_data { __u8 operation; __u8 frag_pref; __u8 length; - __u8 data[]; + __u8 data[] __counted_by(length); } __packed; #define HCI_OP_LE_SET_EXT_ADV_ENABLE 0x2039 @@ -2061,7 +2061,7 @@ struct hci_cp_le_set_per_adv_data { __u8 handle; __u8 operation; __u8 length; - __u8 data[]; + __u8 data[] __counted_by(length); } __packed; #define HCI_OP_LE_SET_PER_ADV_ENABLE 0x2040 @@ -2162,7 +2162,7 @@ struct hci_cis { struct hci_cp_le_create_cis { __u8 num_cis; - struct hci_cis cis[]; + struct hci_cis cis[] __counted_by(num_cis); } __packed; #define HCI_OP_LE_REMOVE_CIG 0x2065 |