[PATCH] ath11k: Correctly check errors for calls to debugfs_create_dir()

From: Alex Dewar
Date: Sun Sep 27 2020 - 09:25:15 EST


debugfs_create_dir() returns an ERR_PTR in case of error, but never a
null pointer. There are a number of places where error-checking code can
accordingly be simplified.

Addresses-Coverity: CID 1497150: Memory - illegal accesses (USE_AFTER_FREE)
Addresses-Coverity: CID 1497158: Memory - illegal accesses (USE_AFTER_FREE)
Addresses-Coverity: CID 1497160: Memory - illegal accesses (USE_AFTER_FREE)
Signed-off-by: Alex Dewar <alex.dewar90@xxxxxxxxx>
---
drivers/net/wireless/ath/ath11k/debugfs.c | 25 +++++------------------
1 file changed, 5 insertions(+), 20 deletions(-)

diff --git a/drivers/net/wireless/ath/ath11k/debugfs.c b/drivers/net/wireless/ath/ath11k/debugfs.c
index 5193b308a992..826dc8ba188f 100644
--- a/drivers/net/wireless/ath/ath11k/debugfs.c
+++ b/drivers/net/wireless/ath/ath11k/debugfs.c
@@ -837,12 +837,8 @@ int ath11k_debugfs_pdev_create(struct ath11k_base *ab)
return 0;

ab->debugfs_soc = debugfs_create_dir(ab->hw_params.name, ab->debugfs_ath11k);
-
- if (IS_ERR_OR_NULL(ab->debugfs_soc)) {
- if (IS_ERR(ab->debugfs_soc))
- return PTR_ERR(ab->debugfs_soc);
- return -ENOMEM;
- }
+ if (IS_ERR(ab->debugfs_soc))
+ return PTR_ERR(ab->debugfs_soc);

debugfs_create_file("simulate_fw_crash", 0600, ab->debugfs_soc, ab,
&fops_simulate_fw_crash);
@@ -863,13 +859,7 @@ int ath11k_debugfs_soc_create(struct ath11k_base *ab)
{
ab->debugfs_ath11k = debugfs_create_dir("ath11k", NULL);

- if (IS_ERR_OR_NULL(ab->debugfs_ath11k)) {
- if (IS_ERR(ab->debugfs_ath11k))
- return PTR_ERR(ab->debugfs_ath11k);
- return -ENOMEM;
- }
-
- return 0;
+ return PTR_ERR_OR_ZERO(ab->debugfs_ath11k);
}

void ath11k_debugfs_soc_destroy(struct ath11k_base *ab)
@@ -1069,13 +1059,8 @@ int ath11k_debugfs_register(struct ath11k *ar)
snprintf(pdev_name, sizeof(pdev_name), "%s%d", "mac", ar->pdev_idx);

ar->debug.debugfs_pdev = debugfs_create_dir(pdev_name, ab->debugfs_soc);
-
- if (IS_ERR_OR_NULL(ar->debug.debugfs_pdev)) {
- if (IS_ERR(ar->debug.debugfs_pdev))
- return PTR_ERR(ar->debug.debugfs_pdev);
-
- return -ENOMEM;
- }
+ if (IS_ERR(ar->debug.debugfs_pdev))
+ return PTR_ERR(ar->debug.debugfs_pdev);

/* Create a symlink under ieee80211/phy* */
snprintf(buf, 100, "../../ath11k/%pd2", ar->debug.debugfs_pdev);
--
2.28.0