From: Hao Ge gehao@kylinos.cn
stable inclusion from stable-v6.10-rc1 commit d4e9a968738bf66d3bb852dd5588d4c7afd6d7f4 category: bugfix bugzilla: https://gitee.com/src-openeuler/kernel/issues/IA8ADN CVE: CVE-2024-39470
Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=...
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In function eventfs_find_events,there is a potential null pointer that may be caused by calling update_events_attr which will perform some operations on the members of the ei struct when ei is NULL.
Hence,When ei->is_freed is set,return NULL directly.
Link: https://lore.kernel.org/linux-trace-kernel/20240513053338.63017-1-hao.ge@lin...
Cc: stable@vger.kernel.org Fixes: 8186fff7ab64 ("tracefs/eventfs: Use root and instance inodes as default ownership") Signed-off-by: Hao Ge gehao@kylinos.cn Signed-off-by: Steven Rostedt (Google) rostedt@goodmis.org Signed-off-by: Yipeng Zou zouyipeng@huawei.com --- fs/tracefs/event_inode.c | 7 +++---- 1 file changed, 3 insertions(+), 4 deletions(-)
diff --git a/fs/tracefs/event_inode.c b/fs/tracefs/event_inode.c index 56d1741fe041..4b6f73e201a4 100644 --- a/fs/tracefs/event_inode.c +++ b/fs/tracefs/event_inode.c @@ -295,10 +295,9 @@ static struct eventfs_inode *eventfs_find_events(struct dentry *dentry) * If the ei is being freed, the ownership of the children * doesn't matter. */ - if (ei->is_freed) { - ei = NULL; - break; - } + if (ei->is_freed) + return NULL; + // Walk upwards until you find the events inode } while (!ei->is_events);