From: Shayne Chen <shayne.chen@mediatek.com> To: linux-wireless <linux-wireless@vger.kernel.org> Cc: "Johannes Berg" <johannes@sipsolutions.net>, "Toke Høiland-Jørgensen" <toke@toke.dk>, "Felix Fietkau" <nbd@nbd.name>, "Lorenzo Bianconi" <lorenzo.bianconi@redhat.com>, "Ryder Lee" <ryder.lee@mediatek.com>, linux-mediatek <linux-mediatek@lists.infradead.org>, "Shayne Chen" <shayne.chen@mediatek.com>, "Sujuan Chen" <sujuan.chen@mediatek.com> Subject: [PATCH v2] mac80211: fix incorrect strlen of .write in debugfs Date: Tue, 12 Jan 2021 11:20:28 +0800 [thread overview] Message-ID: <20210112032028.7482-1-shayne.chen@mediatek.com> (raw) This fixes strlen mismatch problems happening in some .write callbacks of debugfs. When trying to configure airtime_flags in debugfs, an error appeared: ash: write error: Invalid argument The error is returned from kstrtou16() since a wrong length makes it miss the real end of input string. To fix this, use count as the string length, and set proper end of string for a char buffer. The debug print is shown - airtime_flags_write: count = 2, len = 8, where the actual length is 2, but "len = strlen(buf)" gets 8. Also cleanup the other similar cases for the sake of consistency. Signed-off-by: Sujuan Chen <sujuan.chen@mediatek.com> Signed-off-by: Ryder Lee <ryder.lee@mediatek.com> Signed-off-by: Shayne Chen <shayne.chen@mediatek.com> --- v2: - fix r/w buffer OOB - put buf[count] = '\0' to an else --- net/mac80211/debugfs.c | 44 +++++++++++++++++++----------------------- 1 file changed, 20 insertions(+), 24 deletions(-) diff --git a/net/mac80211/debugfs.c b/net/mac80211/debugfs.c index 48f144f107d5..9e723d943421 100644 --- a/net/mac80211/debugfs.c +++ b/net/mac80211/debugfs.c @@ -120,18 +120,17 @@ static ssize_t aqm_write(struct file *file, { struct ieee80211_local *local = file->private_data; char buf[100]; - size_t len; - if (count > sizeof(buf)) + if (count >= sizeof(buf)) return -EINVAL; if (copy_from_user(buf, user_buf, count)) return -EFAULT; - buf[sizeof(buf) - 1] = '\0'; - len = strlen(buf); - if (len > 0 && buf[len-1] == '\n') - buf[len-1] = 0; + if (count && buf[count - 1] == '\n') + buf[count - 1] = '\0'; + else + buf[count] = '\0'; if (sscanf(buf, "fq_limit %u", &local->fq.limit) == 1) return count; @@ -177,18 +176,17 @@ static ssize_t airtime_flags_write(struct file *file, { struct ieee80211_local *local = file->private_data; char buf[16]; - size_t len; - if (count > sizeof(buf)) + if (count >= sizeof(buf)) return -EINVAL; if (copy_from_user(buf, user_buf, count)) return -EFAULT; - buf[sizeof(buf) - 1] = 0; - len = strlen(buf); - if (len > 0 && buf[len - 1] == '\n') - buf[len - 1] = 0; + if (count && buf[count - 1] == '\n') + buf[count - 1] = '\0'; + else + buf[count] = '\0'; if (kstrtou16(buf, 0, &local->airtime_flags)) return -EINVAL; @@ -237,20 +235,19 @@ static ssize_t aql_txq_limit_write(struct file *file, { struct ieee80211_local *local = file->private_data; char buf[100]; - size_t len; u32 ac, q_limit_low, q_limit_high, q_limit_low_old, q_limit_high_old; struct sta_info *sta; - if (count > sizeof(buf)) + if (count >= sizeof(buf)) return -EINVAL; if (copy_from_user(buf, user_buf, count)) return -EFAULT; - buf[sizeof(buf) - 1] = 0; - len = strlen(buf); - if (len > 0 && buf[len - 1] == '\n') - buf[len - 1] = 0; + if (count && buf[count - 1] == '\n') + buf[count - 1] = '\0'; + else + buf[count] = '\0'; if (sscanf(buf, "%u %u %u", &ac, &q_limit_low, &q_limit_high) != 3) return -EINVAL; @@ -306,18 +303,17 @@ static ssize_t force_tx_status_write(struct file *file, { struct ieee80211_local *local = file->private_data; char buf[3]; - size_t len; - if (count > sizeof(buf)) + if (count >= sizeof(buf)) return -EINVAL; if (copy_from_user(buf, user_buf, count)) return -EFAULT; - buf[sizeof(buf) - 1] = '\0'; - len = strlen(buf); - if (len > 0 && buf[len - 1] == '\n') - buf[len - 1] = 0; + if (count && buf[count - 1] == '\n') + buf[count - 1] = '\0'; + else + buf[count] = '\0'; if (buf[0] == '0' && buf[1] == '\0') local->force_tx_status = 0; -- 2.29.2
WARNING: multiple messages have this Message-ID (diff)
From: Shayne Chen <shayne.chen@mediatek.com> To: linux-wireless <linux-wireless@vger.kernel.org> Cc: "Ryder Lee" <ryder.lee@mediatek.com>, "Toke Høiland-Jørgensen" <toke@toke.dk>, linux-mediatek <linux-mediatek@lists.infradead.org>, "Sujuan Chen" <sujuan.chen@mediatek.com>, "Johannes Berg" <johannes@sipsolutions.net>, "Shayne Chen" <shayne.chen@mediatek.com>, "Lorenzo Bianconi" <lorenzo.bianconi@redhat.com>, "Felix Fietkau" <nbd@nbd.name> Subject: [PATCH v2] mac80211: fix incorrect strlen of .write in debugfs Date: Tue, 12 Jan 2021 11:20:28 +0800 [thread overview] Message-ID: <20210112032028.7482-1-shayne.chen@mediatek.com> (raw) This fixes strlen mismatch problems happening in some .write callbacks of debugfs. When trying to configure airtime_flags in debugfs, an error appeared: ash: write error: Invalid argument The error is returned from kstrtou16() since a wrong length makes it miss the real end of input string. To fix this, use count as the string length, and set proper end of string for a char buffer. The debug print is shown - airtime_flags_write: count = 2, len = 8, where the actual length is 2, but "len = strlen(buf)" gets 8. Also cleanup the other similar cases for the sake of consistency. Signed-off-by: Sujuan Chen <sujuan.chen@mediatek.com> Signed-off-by: Ryder Lee <ryder.lee@mediatek.com> Signed-off-by: Shayne Chen <shayne.chen@mediatek.com> --- v2: - fix r/w buffer OOB - put buf[count] = '\0' to an else --- net/mac80211/debugfs.c | 44 +++++++++++++++++++----------------------- 1 file changed, 20 insertions(+), 24 deletions(-) diff --git a/net/mac80211/debugfs.c b/net/mac80211/debugfs.c index 48f144f107d5..9e723d943421 100644 --- a/net/mac80211/debugfs.c +++ b/net/mac80211/debugfs.c @@ -120,18 +120,17 @@ static ssize_t aqm_write(struct file *file, { struct ieee80211_local *local = file->private_data; char buf[100]; - size_t len; - if (count > sizeof(buf)) + if (count >= sizeof(buf)) return -EINVAL; if (copy_from_user(buf, user_buf, count)) return -EFAULT; - buf[sizeof(buf) - 1] = '\0'; - len = strlen(buf); - if (len > 0 && buf[len-1] == '\n') - buf[len-1] = 0; + if (count && buf[count - 1] == '\n') + buf[count - 1] = '\0'; + else + buf[count] = '\0'; if (sscanf(buf, "fq_limit %u", &local->fq.limit) == 1) return count; @@ -177,18 +176,17 @@ static ssize_t airtime_flags_write(struct file *file, { struct ieee80211_local *local = file->private_data; char buf[16]; - size_t len; - if (count > sizeof(buf)) + if (count >= sizeof(buf)) return -EINVAL; if (copy_from_user(buf, user_buf, count)) return -EFAULT; - buf[sizeof(buf) - 1] = 0; - len = strlen(buf); - if (len > 0 && buf[len - 1] == '\n') - buf[len - 1] = 0; + if (count && buf[count - 1] == '\n') + buf[count - 1] = '\0'; + else + buf[count] = '\0'; if (kstrtou16(buf, 0, &local->airtime_flags)) return -EINVAL; @@ -237,20 +235,19 @@ static ssize_t aql_txq_limit_write(struct file *file, { struct ieee80211_local *local = file->private_data; char buf[100]; - size_t len; u32 ac, q_limit_low, q_limit_high, q_limit_low_old, q_limit_high_old; struct sta_info *sta; - if (count > sizeof(buf)) + if (count >= sizeof(buf)) return -EINVAL; if (copy_from_user(buf, user_buf, count)) return -EFAULT; - buf[sizeof(buf) - 1] = 0; - len = strlen(buf); - if (len > 0 && buf[len - 1] == '\n') - buf[len - 1] = 0; + if (count && buf[count - 1] == '\n') + buf[count - 1] = '\0'; + else + buf[count] = '\0'; if (sscanf(buf, "%u %u %u", &ac, &q_limit_low, &q_limit_high) != 3) return -EINVAL; @@ -306,18 +303,17 @@ static ssize_t force_tx_status_write(struct file *file, { struct ieee80211_local *local = file->private_data; char buf[3]; - size_t len; - if (count > sizeof(buf)) + if (count >= sizeof(buf)) return -EINVAL; if (copy_from_user(buf, user_buf, count)) return -EFAULT; - buf[sizeof(buf) - 1] = '\0'; - len = strlen(buf); - if (len > 0 && buf[len - 1] == '\n') - buf[len - 1] = 0; + if (count && buf[count - 1] == '\n') + buf[count - 1] = '\0'; + else + buf[count] = '\0'; if (buf[0] == '0' && buf[1] == '\0') local->force_tx_status = 0; -- 2.29.2 _______________________________________________ Linux-mediatek mailing list Linux-mediatek@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-mediatek
next reply other threads:[~2021-01-12 3:26 UTC|newest] Thread overview: 2+ messages / expand[flat|nested] mbox.gz Atom feed top 2021-01-12 3:20 Shayne Chen [this message] 2021-01-12 3:20 ` [PATCH v2] mac80211: fix incorrect strlen of .write in debugfs Shayne Chen
Reply instructions: You may reply publicly to this message via plain-text email using any one of the following methods: * Save the following mbox file, import it into your mail client, and reply-to-all from there: mbox Avoid top-posting and favor interleaved quoting: https://en.wikipedia.org/wiki/Posting_style#Interleaved_style * Reply using the --to, --cc, and --in-reply-to switches of git-send-email(1): git send-email \ --in-reply-to=20210112032028.7482-1-shayne.chen@mediatek.com \ --to=shayne.chen@mediatek.com \ --cc=johannes@sipsolutions.net \ --cc=linux-mediatek@lists.infradead.org \ --cc=linux-wireless@vger.kernel.org \ --cc=lorenzo.bianconi@redhat.com \ --cc=nbd@nbd.name \ --cc=ryder.lee@mediatek.com \ --cc=sujuan.chen@mediatek.com \ --cc=toke@toke.dk \ /path/to/YOUR_REPLY https://kernel.org/pub/software/scm/git/docs/git-send-email.html * If your mail client supports setting the In-Reply-To header via mailto: links, try the mailto: linkBe sure your reply has a Subject: header at the top and a blank line before the message body.
This is an external index of several public inboxes, see mirroring instructions on how to clone and mirror all data and code used by this external index.