MIRRORS/linux-yocto
1
0
Fork 0
mirror of git://git.yoctoproject.org/linux-yocto.git synced 2025-10-22 23:13:01 +02:00
Code Issues Actions Packages Projects Releases Wiki Activity

wifi: iwlegacy: Fix "field-spanning write" warning in il_enqueue_hcmd()

Browse Source 
iwlegacy uses command buffers with a payload size of 320
bytes (default) or 4092 bytes (huge).  The struct il_device_cmd type
describes the default buffers and there is no separate type describing
the huge buffers.

The il_enqueue_hcmd() function works with both default and huge
buffers, and has a memcpy() to the buffer payload.  The size of
this copy may exceed 320 bytes when using a huge buffer, which
now results in a run-time warning:

    memcpy: detected field-spanning write (size 1014) of single field "&out_cmd->cmd.payload" at drivers/net/wireless/intel/iwlegacy/common.c:3170 (size 320)

To fix this:

- Define a new struct type for huge buffers, with a correctly sized
  payload field
- When using a huge buffer in il_enqueue_hcmd(), cast the command
  buffer pointer to that type when looking up the payload field

Reported-by: Martin-Éric Racine <martin-eric.racine@iki.fi>
References: https://bugs.debian.org/1062421
References: https://bugzilla.kernel.org/show_bug.cgi?id=219124
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Fixes: 54d9469bc5 ("fortify: Add run-time WARN for cross-field memcpy()")
Tested-by: Martin-Éric Racine <martin-eric.racine@iki.fi>
Tested-by: Brandon Nielsen <nielsenb@jetfuse.net>
Acked-by: Stanislaw Gruszka <stf_xl@wp.pl>
Signed-off-by: Kalle Valo <kvalo@kernel.org>
Link: https://patch.msgid.link/ZuIhQRi/791vlUhE@decadent.org.uk
This commit is contained in:
Ben Hutchings 2024-09-12 01:01:21 +02:00 committed by Kalle Valo
parent 34b6954810
commit d4cdc46ca1
2 changed files with 24 additions and 1 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

13
drivers/net/wireless/intel/iwlegacy/common.c
View File

@ -3122,6 +3122,7 @@ il_enqueue_hcmd(struct il_priv *il, struct il_host_cmd *cmd)
struct il_cmd_meta *out_meta;
dma_addr_t phys_addr;
unsigned long flags;
u8 *out_payload;
u32 idx;
u16 fix_size;
@ -3157,6 +3158,16 @@ il_enqueue_hcmd(struct il_priv *il, struct il_host_cmd *cmd)
out_cmd = txq->cmd[idx];
out_meta = &txq->meta[idx];
/* The payload is in the same place in regular and huge
* command buffers, but we need to let the compiler know when
* we're using a larger payload buffer to avoid "field-
* spanning write" warnings at run-time for huge commands.
*/
if (cmd->flags & CMD_SIZE_HUGE)
out_payload = ((struct il_device_cmd_huge *)out_cmd)->cmd.payload;
else
out_payload = out_cmd->cmd.payload;
if (WARN_ON(out_meta->flags & CMD_MAPPED)) {
spin_unlock_irqrestore(&il->hcmd_lock, flags);
return -ENOSPC;
@ -3170,7 +3181,7 @@ il_enqueue_hcmd(struct il_priv *il, struct il_host_cmd *cmd)
out_meta->callback = cmd->callback;
out_cmd->hdr.cmd = cmd->id;
memcpy(&out_cmd->cmd.payload, cmd->data, cmd->len);
memcpy(out_payload, cmd->data, cmd->len);
/* At this point, the out_cmd now has all of the incoming cmd
* information */

12
drivers/net/wireless/intel/iwlegacy/common.h
View File

@ -560,6 +560,18 @@ struct il_device_cmd {
#define TFD_MAX_PAYLOAD_SIZE (sizeof(struct il_device_cmd))
/**
* struct il_device_cmd_huge
*
* For use when sending huge commands.
*/
struct il_device_cmd_huge {
struct il_cmd_header hdr; /* uCode API */
union {
u8 payload[IL_MAX_CMD_SIZE - sizeof(struct il_cmd_header)];
} __packed cmd;
} __packed;
struct il_host_cmd {
const void *data;
unsigned long reply_page;