Commit 80eb68d2 authored Oct 16, 2007 by Lepton Wu Committed by Linus Torvalds Oct 17, 2007

reiserfs: fix kernel panic on corrupted directory

When reading corrupted reiserfs directory data, d_reclen could be a
negative number or a big positive number, this can lead to kernel panic or
oop.  The following patch adds a sanity check.

Signed-off-by: Lepton Wu <ytht.net@gmail.com>
Cc: Chris Mason <chris.mason@oracle.com>
Cc: Jeff Mahoney <jeffm@suse.com>
Cc: "Vladimir V. Saveliev" <vs@namesys.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

parent a6cd6bf9

fs/reiserfs/dir.c

+10 −0

Original line number	Diff line number	Diff line
		@@ -121,6 +121,16 @@ static int reiserfs_readdir(struct file filp, void dirent, filldir_t filldir)
		continue;
		d_reclen = entry_length(bh, ih, entry_num);
		d_name = B_I_DEH_ENTRY_FILE_NAME(bh, ih, deh);

		if (d_reclen <= 0 \|\|
		d_name + d_reclen > bh->b_data + bh->b_size) {
		/* There is corrupted data in entry,
		* We'd better stop here */
		pathrelse(&path_to_entry);
		ret = -EIO;
		goto out;
		}

		if (!d_name[d_reclen - 1])
		d_reclen = strlen(d_name);

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