Re: [PATCH ] ext3: Fix a possible corruption in dx_probe.
From: Jan Kara <jack@suse.cz>
Date: 2011-09-01 16:43:35
On Wed 31-08-11 23:57:24, Tao Ma wrote:
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.
I think this happens at the beginning of dx_probe(). Honza
quoted hunk ↗ jump to hunk
Cc: Jan Kara <jack@suse.cz> Signed-off-by: Tao Ma <redacted> --- fs/ext3/namei.c | 2 +- 1 files changed, 1 insertions(+), 1 deletions(-)diff --git a/fs/ext3/namei.c b/fs/ext3/namei.c index 34b6d9b..45468b9 100644 --- a/fs/ext3/namei.c +++ b/fs/ext3/namei.c@@ -404,6 +404,7 @@ dx_probe(struct qstr *entry, 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)) { ext3_warning(dir->i_sb, __func__,@@ -458,7 +459,6 @@ dx_probe(struct qstr *entry, struct inode *dir, goto fail2; } frame++; - frame->bh = NULL; } fail2: while (frame >= frame_in) {-- 1.7.0.4
-- Jan Kara [off-list ref] SUSE Labs, CR