From: Arnd Bergmann <arnd@xxxxxxxx> commit 7909a590eba6d021f104958857cbc4f0089daceb upstream. gcc-11 with KASAN on 32-bit arm produces a warning about a function that needs a lot of stack space: drivers/net/wireless/cisco/airo.c: In function 'setup_card.constprop': drivers/net/wireless/cisco/airo.c:3960:1: error: the frame size of 1512 bytes is larger than 1400 bytes [-Werror=frame-larger-than=] Most of this is from a single large structure that could be dynamically allocated or moved into the per-device structure. However, as the callers all seem to have a fairly well bounded call chain, the easiest change is to pull out the part of the function that needs the large variables into a separate function and mark that as noinline_for_stack. This does not reduce the total stack usage, but it gets rid of the warning and requires minimal changes otherwise. Signed-off-by: Arnd Bergmann <arnd@xxxxxxxx> Signed-off-by: Kalle Valo <kvalo@xxxxxxxxxxxxxx> Link: https://lore.kernel.org/r/20210323131634.2669455-1-arnd@xxxxxxxxxx Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/net/wireless/cisco/airo.c | 117 +++++++++++++++++++++----------------- 1 file changed, 65 insertions(+), 52 deletions(-) --- a/drivers/net/wireless/cisco/airo.c +++ b/drivers/net/wireless/cisco/airo.c @@ -3825,6 +3825,68 @@ static inline void set_auth_type(struct local->last_auth = auth_type; } +static int noinline_for_stack airo_readconfig(struct airo_info *ai, u8 *mac, int lock) +{ + int i, status; + /* large variables, so don't inline this function, + * maybe change to kmalloc + */ + tdsRssiRid rssi_rid; + CapabilityRid cap_rid; + + kfree(ai->SSID); + ai->SSID = NULL; + // general configuration (read/modify/write) + status = readConfigRid(ai, lock); + if (status != SUCCESS) return ERROR; + + status = readCapabilityRid(ai, &cap_rid, lock); + if (status != SUCCESS) return ERROR; + + status = PC4500_readrid(ai, RID_RSSI, &rssi_rid, sizeof(rssi_rid), lock); + if (status == SUCCESS) { + if (ai->rssi || (ai->rssi = kmalloc(512, GFP_KERNEL)) != NULL) + memcpy(ai->rssi, (u8*)&rssi_rid + 2, 512); /* Skip RID length member */ + } + else { + kfree(ai->rssi); + ai->rssi = NULL; + if (cap_rid.softCap & cpu_to_le16(8)) + ai->config.rmode |= RXMODE_NORMALIZED_RSSI; + else + airo_print_warn(ai->dev->name, "unknown received signal " + "level scale"); + } + ai->config.opmode = adhoc ? MODE_STA_IBSS : MODE_STA_ESS; + set_auth_type(ai, AUTH_OPEN); + ai->config.modulation = MOD_CCK; + + if (le16_to_cpu(cap_rid.len) >= sizeof(cap_rid) && + (cap_rid.extSoftCap & cpu_to_le16(1)) && + micsetup(ai) == SUCCESS) { + ai->config.opmode |= MODE_MIC; + set_bit(FLAG_MIC_CAPABLE, &ai->flags); + } + + /* Save off the MAC */ + for (i = 0; i < ETH_ALEN; i++) { + mac[i] = ai->config.macAddr[i]; + } + + /* Check to see if there are any insmod configured + rates to add */ + if (rates[0]) { + memset(ai->config.rates, 0, sizeof(ai->config.rates)); + for (i = 0; i < 8 && rates[i]; i++) { + ai->config.rates[i] = rates[i]; + } + } + set_bit (FLAG_COMMIT, &ai->flags); + + return SUCCESS; +} + + static u16 setup_card(struct airo_info *ai, u8 *mac, int lock) { Cmd cmd; @@ -3871,58 +3933,9 @@ static u16 setup_card(struct airo_info * if (lock) up(&ai->sem); if (ai->config.len == 0) { - int i; - tdsRssiRid rssi_rid; - CapabilityRid cap_rid; - - kfree(ai->SSID); - ai->SSID = NULL; - // general configuration (read/modify/write) - status = readConfigRid(ai, lock); - if (status != SUCCESS) return ERROR; - - status = readCapabilityRid(ai, &cap_rid, lock); - if (status != SUCCESS) return ERROR; - - status = PC4500_readrid(ai, RID_RSSI,&rssi_rid, sizeof(rssi_rid), lock); - if (status == SUCCESS) { - if (ai->rssi || (ai->rssi = kmalloc(512, GFP_KERNEL)) != NULL) - memcpy(ai->rssi, (u8*)&rssi_rid + 2, 512); /* Skip RID length member */ - } - else { - kfree(ai->rssi); - ai->rssi = NULL; - if (cap_rid.softCap & cpu_to_le16(8)) - ai->config.rmode |= RXMODE_NORMALIZED_RSSI; - else - airo_print_warn(ai->dev->name, "unknown received signal " - "level scale"); - } - ai->config.opmode = adhoc ? MODE_STA_IBSS : MODE_STA_ESS; - set_auth_type(ai, AUTH_OPEN); - ai->config.modulation = MOD_CCK; - - if (le16_to_cpu(cap_rid.len) >= sizeof(cap_rid) && - (cap_rid.extSoftCap & cpu_to_le16(1)) && - micsetup(ai) == SUCCESS) { - ai->config.opmode |= MODE_MIC; - set_bit(FLAG_MIC_CAPABLE, &ai->flags); - } - - /* Save off the MAC */ - for (i = 0; i < ETH_ALEN; i++) { - mac[i] = ai->config.macAddr[i]; - } - - /* Check to see if there are any insmod configured - rates to add */ - if (rates[0]) { - memset(ai->config.rates, 0, sizeof(ai->config.rates)); - for (i = 0; i < 8 && rates[i]; i++) { - ai->config.rates[i] = rates[i]; - } - } - set_bit (FLAG_COMMIT, &ai->flags); + status = airo_readconfig(ai, mac, lock); + if (status != SUCCESS) + return ERROR; } /* Setup the SSIDs if present */
