diff options
author | Jacob Keller <jacob.e.keller@intel.com> | 2023-03-07 15:01:48 -0800 |
---|---|---|
committer | Kalle Valo <kvalo@kernel.org> | 2023-03-13 15:44:15 +0200 |
commit | a23c82e006db2f073fb65da8762f63735a510409 (patch) | |
tree | 7b7174addd45886f47f51d1a96fa10804a9e7f1b /drivers/net/wireless/intel/ipw2x00 | |
parent | 0606b344021a37140ef467ddf30d4b8182e7bbe1 (diff) |
wifi: ipw2x00: convert ipw_fw_error->elem to flexible array[]
The ipw_fw_error structure contains a payload[] flexible array as well as
two pointers to this array area, ->elem, and ->log. The total size of the
allocated structure is computed without use of the <linux/overflow.h>
macros.
There's no reason to keep both a payload[] and an extra pointer to both the
elem and log members. Convert the elem pointer member into the flexible
array member, removing payload.
Fix the allocation of the ipw_fw_error structure to use size_add(),
struct_size(), and array_size() to compute the allocation. This ensures
that any overflow saturates at SIZE_MAX rather than overflowing and
potentially allowing an undersized allocation.
Before the structure change, the layout of ipw_fw_error was:
struct ipw_fw_error {
long unsigned int jiffies; /* 0 8 */
u32 status; /* 8 4 */
u32 config; /* 12 4 */
u32 elem_len; /* 16 4 */
u32 log_len; /* 20 4 */
struct ipw_error_elem * elem; /* 24 8 */
struct ipw_event * log; /* 32 8 */
u8 payload[]; /* 40 0 */
/* size: 40, cachelines: 1, members: 8 */
/* last cacheline: 40 bytes */
};
After this change, the layout is now:
struct ipw_fw_error {
long unsigned int jiffies; /* 0 8 */
u32 status; /* 8 4 */
u32 config; /* 12 4 */
u32 elem_len; /* 16 4 */
u32 log_len; /* 20 4 */
struct ipw_event * log; /* 24 8 */
struct ipw_error_elem elem[]; /* 32 0 */
/* size: 32, cachelines: 1, members: 7 */
/* last cacheline: 32 bytes */
};
This saves a total of 8 bytes for every ipw_fw_error allocation, and
removes the risk of a potential overflow on the allocation.
Signed-off-by: Jacob Keller <jacob.e.keller@intel.com>
Cc: Stanislav Yakovlev <stas.yakovlev@gmail.com>
Signed-off-by: Kalle Valo <kvalo@kernel.org>
Link: https://lore.kernel.org/r/20230307230148.3735684-1-jacob.e.keller@intel.com
Diffstat (limited to 'drivers/net/wireless/intel/ipw2x00')
-rw-r--r-- | drivers/net/wireless/intel/ipw2x00/ipw2200.c | 7 | ||||
-rw-r--r-- | drivers/net/wireless/intel/ipw2x00/ipw2200.h | 3 |
2 files changed, 4 insertions, 6 deletions
diff --git a/drivers/net/wireless/intel/ipw2x00/ipw2200.c b/drivers/net/wireless/intel/ipw2x00/ipw2200.c index d382f2017325..b91b1a2d0be7 100644 --- a/drivers/net/wireless/intel/ipw2x00/ipw2200.c +++ b/drivers/net/wireless/intel/ipw2x00/ipw2200.c @@ -1234,9 +1234,9 @@ static struct ipw_fw_error *ipw_alloc_error_log(struct ipw_priv *priv) u32 base = ipw_read32(priv, IPW_ERROR_LOG); u32 elem_len = ipw_read_reg32(priv, base); - error = kmalloc(sizeof(*error) + - sizeof(*error->elem) * elem_len + - sizeof(*error->log) * log_len, GFP_ATOMIC); + error = kmalloc(size_add(struct_size(error, elem, elem_len), + array_size(sizeof(*error->log), log_len)), + GFP_ATOMIC); if (!error) { IPW_ERROR("Memory allocation for firmware error log " "failed.\n"); @@ -1247,7 +1247,6 @@ static struct ipw_fw_error *ipw_alloc_error_log(struct ipw_priv *priv) error->config = priv->config; error->elem_len = elem_len; error->log_len = log_len; - error->elem = (struct ipw_error_elem *)error->payload; error->log = (struct ipw_event *)(error->elem + elem_len); ipw_capture_event_log(priv, log_len, error->log); diff --git a/drivers/net/wireless/intel/ipw2x00/ipw2200.h b/drivers/net/wireless/intel/ipw2x00/ipw2200.h index 09ddd21608d4..8ebf09121e17 100644 --- a/drivers/net/wireless/intel/ipw2x00/ipw2200.h +++ b/drivers/net/wireless/intel/ipw2x00/ipw2200.h @@ -1106,9 +1106,8 @@ struct ipw_fw_error { /* XXX */ u32 config; u32 elem_len; u32 log_len; - struct ipw_error_elem *elem; struct ipw_event *log; - u8 payload[]; + struct ipw_error_elem elem[]; } __packed; #ifdef CONFIG_IPW2200_PROMISCUOUS |