Commit 8bf3d79bc401ca417ccf9fc076d3295d1a71dbf5 enabled EEPROM checksum checks to avoid bogus bug reports but failed to address updating the code to consider devices with custom EEPROM sizes. Devices with custom sized EEPROMs have the upper limit size stuffed in the EEPROM. Use this as the upper limit instead of the static default size. In case of a checksum error also provide back the max size and whether or not this was the default size or a custom one. If the EEPROM is busted we add a failsafe check to ensure we don't loop forever or try to read bogus areas of hardware. This closes bug 14874 http://bugzilla.kernel.org/show_bug.cgi?id=14874 Cc: stable@xxxxxxxxxx Cc: David Quan <david.quan@xxxxxxxxxxx> Cc: Stephen Beahm <stephenbeahm@xxxxxxxxxxx> Reported-by: Joshua Covington <joshuacov@xxxxxxxxxxxxxx> Signed-off-by: Luis R. Rodriguez <lrodriguez@xxxxxxxxxxx> --- This should apply on >= 2.6.32.2 cleanly. This is not applicable to older kernels. drivers/net/wireless/ath/ath5k/eeprom.c | 32 ++++++++++++++++++++++++++++-- drivers/net/wireless/ath/ath5k/eeprom.h | 8 +++++++ 2 files changed, 37 insertions(+), 3 deletions(-) diff --git a/drivers/net/wireless/ath/ath5k/eeprom.c b/drivers/net/wireless/ath/ath5k/eeprom.c index 5d1c867..6a3f4da 100644 --- a/drivers/net/wireless/ath/ath5k/eeprom.c +++ b/drivers/net/wireless/ath/ath5k/eeprom.c @@ -97,7 +97,7 @@ ath5k_eeprom_init_header(struct ath5k_hw *ah) struct ath5k_eeprom_info *ee = &ah->ah_capabilities.cap_eeprom; int ret; u16 val; - u32 cksum, offset; + u32 cksum, offset, eep_max = AR5K_EEPROM_INFO_MAX; /* * Read values from EEPROM and store them in the capability structure @@ -116,12 +116,38 @@ ath5k_eeprom_init_header(struct ath5k_hw *ah) * Validate the checksum of the EEPROM date. There are some * devices with invalid EEPROMs. */ - for (cksum = 0, offset = 0; offset < AR5K_EEPROM_INFO_MAX; offset++) { + AR5K_EEPROM_READ(AR5K_EEPROM_SIZE_UPPER, val); + if (val) { + eep_max = (val & AR5K_EEPROM_SIZE_UPPER_MASK) << + AR5K_EEPROM_SIZE_ENDLOC_SHIFT; + AR5K_EEPROM_READ(AR5K_EEPROM_SIZE_LOWER, val); + eep_max = (eep_max | val) - AR5K_EEPROM_INFO_BASE; + + /* + * Fail safe check to prevent stupid loops due + * to busted EEPROMs. XXX: This value is likely too + * big still, waiting on a better value. + */ + if (eep_max > (3 * AR5K_EEPROM_INFO_MAX)) { + ATH5K_ERR(ah->ah_sc, "Invalid max custom EEPROM size: " + "%d (0x%04x) max expected: %d (0x%04x)\n", + eep_max, eep_max, + 3 * AR5K_EEPROM_INFO_MAX, + 3 * AR5K_EEPROM_INFO_MAX); + return -EIO; + } + } + + for (cksum = 0, offset = 0; offset < eep_max; offset++) { AR5K_EEPROM_READ(AR5K_EEPROM_INFO(offset), val); cksum ^= val; } if (cksum != AR5K_EEPROM_INFO_CKSUM) { - ATH5K_ERR(ah->ah_sc, "Invalid EEPROM checksum 0x%04x\n", cksum); + ATH5K_ERR(ah->ah_sc, "Invalid EEPROM " + "checksum: 0x%04x eep_max: 0x%04x (%s)\n", + cksum, eep_max, + eep_max == AR5K_EEPROM_INFO_MAX ? + "default size" : "custom size"); return -EIO; } diff --git a/drivers/net/wireless/ath/ath5k/eeprom.h b/drivers/net/wireless/ath/ath5k/eeprom.h index 0123f35..473a483 100644 --- a/drivers/net/wireless/ath/ath5k/eeprom.h +++ b/drivers/net/wireless/ath/ath5k/eeprom.h @@ -37,6 +37,14 @@ #define AR5K_EEPROM_RFKILL_POLARITY_S 1 #define AR5K_EEPROM_REG_DOMAIN 0x00bf /* EEPROM regdom */ + +/* FLASH(EEPROM) Defines for AR531X chips */ +#define AR5K_EEPROM_SIZE_LOWER 0x1b /* size info -- lower */ +#define AR5K_EEPROM_SIZE_UPPER 0x1c /* size info -- upper */ +#define AR5K_EEPROM_SIZE_UPPER_MASK 0xfff0 +#define AR5K_EEPROM_SIZE_UPPER_SHIFT 4 +#define AR5K_EEPROM_SIZE_ENDLOC_SHIFT 12 + #define AR5K_EEPROM_CHECKSUM 0x00c0 /* EEPROM checksum */ #define AR5K_EEPROM_INFO_BASE 0x00c0 /* EEPROM header */ #define AR5K_EEPROM_INFO_MAX (0x400 - AR5K_EEPROM_INFO_BASE) -- 1.6.3.3 -- To unsubscribe from this list: send the line "unsubscribe linux-wireless" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
