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authorJanusz Dziedzic <janusz.dziedzic@tieto.com>2013-11-02 00:05:28 +0400
committerJohn W. Linville <linville@tuxdriver.com>2013-11-11 23:42:43 +0400
commit4be6718c669bce10e9f709e2be68db2c5e22c4f0 (patch)
treed9716243b7813a798518a1e82f81eb958d39a51e /drivers/net/wireless/ath/ath9k/dfs_debug.c
parent87eb01679a9084bc9a4ba3c92c5692def116fffc (diff)
downloadlinux-4be6718c669bce10e9f709e2be68db2c5e22c4f0.tar.xz
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 <janusz.dziedzic@tieto.com> Signed-off-by: John W. Linville <linville@tuxdriver.com>
Diffstat (limited to 'drivers/net/wireless/ath/ath9k/dfs_debug.c')
-rw-r--r--drivers/net/wireless/ath/ath9k/dfs_debug.c13
1 files changed, 10 insertions, 3 deletions
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;