From 8aada63cc408874916a19341ba514f941096e424 Mon Sep 17 00:00:00 2001 From: Djalal Harouni Date: Sun, 25 Aug 2013 11:50:49 +0100 Subject: [PATCH] ath5k: debugfs: NULL-terminate strings Avoid processing garbage data by NULL terminating the strings. Signed-off-by: Djalal Harouni Signed-off-by: John W. Linville --- drivers/net/wireless/ath/ath5k/debug.c | 24 ++++++++++++++++++------ 1 file changed, 18 insertions(+), 6 deletions(-) diff --git a/drivers/net/wireless/ath/ath5k/debug.c b/drivers/net/wireless/ath/ath5k/debug.c index 9d00dab666a8..b8d031ae63c2 100644 --- a/drivers/net/wireless/ath/ath5k/debug.c +++ b/drivers/net/wireless/ath/ath5k/debug.c @@ -245,9 +245,11 @@ static ssize_t write_file_beacon(struct file *file, struct ath5k_hw *ah = file->private_data; char buf[20]; - if (copy_from_user(buf, userbuf, min(count, sizeof(buf)))) + count = min_t(size_t, count, sizeof(buf) - 1); + if (copy_from_user(buf, userbuf, count)) return -EFAULT; + buf[count] = '\0'; if (strncmp(buf, "disable", 7) == 0) { AR5K_REG_DISABLE_BITS(ah, AR5K_BEACON, AR5K_BEACON_ENABLE); pr_info("debugfs disable beacons\n"); @@ -345,9 +347,11 @@ static ssize_t write_file_debug(struct file *file, unsigned int i; char buf[20]; - if (copy_from_user(buf, userbuf, min(count, sizeof(buf)))) + count = min_t(size_t, count, sizeof(buf) - 1); + if (copy_from_user(buf, userbuf, count)) return -EFAULT; + buf[count] = '\0'; for (i = 0; i < ARRAY_SIZE(dbg_info); i++) { if (strncmp(buf, dbg_info[i].name, strlen(dbg_info[i].name)) == 0) { @@ -448,9 +452,11 @@ static ssize_t write_file_antenna(struct file *file, unsigned int i; char buf[20]; - if (copy_from_user(buf, userbuf, min(count, sizeof(buf)))) + count = min_t(size_t, count, sizeof(buf) - 1); + if (copy_from_user(buf, userbuf, count)) return -EFAULT; + buf[count] = '\0'; if (strncmp(buf, "diversity", 9) == 0) { ath5k_hw_set_antenna_mode(ah, AR5K_ANTMODE_DEFAULT); pr_info("debug: enable diversity\n"); @@ -619,9 +625,11 @@ static ssize_t write_file_frameerrors(struct file *file, struct ath5k_statistics *st = &ah->stats; char buf[20]; - if (copy_from_user(buf, userbuf, min(count, sizeof(buf)))) + count = min_t(size_t, count, sizeof(buf) - 1); + if (copy_from_user(buf, userbuf, count)) return -EFAULT; + buf[count] = '\0'; if (strncmp(buf, "clear", 5) == 0) { st->rxerr_crc = 0; st->rxerr_phy = 0; @@ -766,9 +774,11 @@ static ssize_t write_file_ani(struct file *file, struct ath5k_hw *ah = file->private_data; char buf[20]; - if (copy_from_user(buf, userbuf, min(count, sizeof(buf)))) + count = min_t(size_t, count, sizeof(buf) - 1); + if (copy_from_user(buf, userbuf, count)) return -EFAULT; + buf[count] = '\0'; if (strncmp(buf, "sens-low", 8) == 0) { ath5k_ani_init(ah, ATH5K_ANI_MODE_MANUAL_HIGH); } else if (strncmp(buf, "sens-high", 9) == 0) { @@ -862,9 +872,11 @@ static ssize_t write_file_queue(struct file *file, struct ath5k_hw *ah = file->private_data; char buf[20]; - if (copy_from_user(buf, userbuf, min(count, sizeof(buf)))) + count = min_t(size_t, count, sizeof(buf) - 1); + if (copy_from_user(buf, userbuf, count)) return -EFAULT; + buf[count] = '\0'; if (strncmp(buf, "start", 5) == 0) ieee80211_wake_queues(ah->hw); else if (strncmp(buf, "stop", 4) == 0) -- 2.20.1