From: Janusz Dziedzic Date: Fri, 1 Nov 2013 20:05:28 +0000 (+0100) Subject: ath9k: dfs_debug fix possible NULL dereference X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=4be6718c669bce10e9f709e2be68db2c5e22c4f0;p=GitHub%2Fexynos8895%2Fandroid_kernel_samsung_universal8895.git ath9k: dfs_debug fix possible NULL dereference Fix possible NULL (sc->dfs_detector) pointer dereference. Detected by Smatch: drivers/net/wireless/ath/ath9k/dfs_debug.c:67 read_file_dfs() error: we previously assumed 'sc->dfs_detector' could be null (see line 47) Signed-off-by: Janusz Dziedzic Signed-off-by: John W. Linville --- diff --git a/drivers/net/wireless/ath/ath9k/dfs_debug.c b/drivers/net/wireless/ath/ath9k/dfs_debug.c index 90b8342d1ed4..8824610c21fb 100644 --- a/drivers/net/wireless/ath/ath9k/dfs_debug.c +++ b/drivers/net/wireless/ath/ath9k/dfs_debug.c @@ -44,14 +44,20 @@ static ssize_t read_file_dfs(struct file *file, char __user *user_buf, if (buf == NULL) return -ENOMEM; - if (sc->dfs_detector) - dfs_pool_stats = sc->dfs_detector->get_stats(sc->dfs_detector); - len += scnprintf(buf + len, size - len, "DFS support for " "macVersion = 0x%x, macRev = 0x%x: %s\n", hw_ver->macVersion, hw_ver->macRev, (sc->sc_ah->caps.hw_caps & ATH9K_HW_CAP_DFS) ? "enabled" : "disabled"); + + if (!sc->dfs_detector) { + len += scnprintf(buf + len, size - len, + "DFS detector not enabled\n"); + goto exit; + } + + dfs_pool_stats = sc->dfs_detector->get_stats(sc->dfs_detector); + len += scnprintf(buf + len, size - len, "Pulse detector statistics:\n"); ATH9K_DFS_STAT("pulse events reported ", pulses_total); ATH9K_DFS_STAT("invalid pulse events ", pulses_no_dfs); @@ -76,6 +82,7 @@ static ssize_t read_file_dfs(struct file *file, char __user *user_buf, ATH9K_DFS_POOL_STAT("Seqs. alloc error ", pseq_alloc_error); ATH9K_DFS_POOL_STAT("Seqs. in use ", pseq_used); +exit: if (len > size) len = size;