From 73bb3e4a7a9f1b8d5f89c3991bd0c904ab0b8e27 Mon Sep 17 00:00:00 2001 From: Luis Carlos Cobo Date: Mon, 31 Mar 2008 15:10:22 -0700 Subject: [PATCH] mac80211: fix deadlocks in debugfs_netdev.c The bug shows up with CONFIG_PREEMPT enabled. Pointed out by Andrew Morton. Cc: Andrew Morton Cc: Johannes Berg Signed-off-by: Luis Carlos Cobo Signed-off-by: John W. Linville --- net/mac80211/debugfs_netdev.c | 14 ++++++++------ 1 file changed, 8 insertions(+), 6 deletions(-) diff --git a/net/mac80211/debugfs_netdev.c b/net/mac80211/debugfs_netdev.c index 0e921aef8ecf..3e19d42e61cb 100644 --- a/net/mac80211/debugfs_netdev.c +++ b/net/mac80211/debugfs_netdev.c @@ -31,11 +31,13 @@ static ssize_t ieee80211_if_read( ssize_t ret = -EINVAL; read_lock(&dev_base_lock); - if (sdata->dev->reg_state == NETREG_REGISTERED) { + if (sdata->dev->reg_state == NETREG_REGISTERED) ret = (*format)(sdata, buf, sizeof(buf)); - ret = simple_read_from_buffer(userbuf, count, ppos, buf, ret); - } read_unlock(&dev_base_lock); + + if (ret != -EINVAL) + ret = simple_read_from_buffer(userbuf, count, ppos, buf, ret); + return ret; } @@ -51,13 +53,13 @@ static ssize_t ieee80211_if_write( memset(buf, 0x00, sizeof(buf)); buf_size = min(count, (sizeof(buf)-1)); - read_lock(&dev_base_lock); if (copy_from_user(buf, userbuf, buf_size)) - goto endwrite; + return count; + read_lock(&dev_base_lock); if (sdata->dev->reg_state == NETREG_REGISTERED) (*format)(sdata, buf); -endwrite: read_unlock(&dev_base_lock); + return count; } #endif -- GitLab