[PATCH] ext4: Fix a possible corruption in dx_probe.
From: Tao Ma <hidden>
Date: 2011-08-31 16:03:05
Subsystem:
ext4 file system, filesystems (vfs and infrastructure), the rest · Maintainers:
"Theodore Ts'o", Alexander Viro, Christian Brauner, Linus Torvalds
From: Tao Ma <redacted> For all the callers of dx_probe, frame_in is passed in uninitialized. So we should set frame->bh to NULL in the beginning of while, not the end. Otherwise, the first "goto fail2" will try to brelse(frame->bh) while frame->bh is still invalid. Cc: "Theodore Ts'o" <tytso@mit.edu> Signed-off-by: Tao Ma <redacted> --- fs/ext4/namei.c | 2 +- 1 files changed, 1 insertions(+), 1 deletions(-)
diff --git a/fs/ext4/namei.c b/fs/ext4/namei.c
index b754b77..86c5c69 100644
--- a/fs/ext4/namei.c
+++ b/fs/ext4/namei.c@@ -404,6 +404,7 @@ dx_probe(const struct qstr *d_name, struct inode *dir, dxtrace(printk("Look up %x", hash)); while (1) { + frame->bh = NULL; count = dx_get_count(entries); if (!count || count > dx_get_limit(entries)) { ext4_warning(dir->i_sb,
@@ -458,7 +459,6 @@ dx_probe(const struct qstr *d_name, struct inode *dir, goto fail2; } frame++; - frame->bh = NULL; } fail2: while (frame >= frame_in) {
--
1.7.0.4