Hi, When reading corrupted reiserfs directory data, d_reclen could be a negative number, then memcpy will overflow kernel stack. This can lead to kernel panic. The following patch adds a sanity check. (against 2.6.20.4) Signed-off-by: Lepton Wu <[EMAIL PROTECTED]>
diff -pru linux-2.6/fs/reiserfs/dir.c linux-2.6-lepton/fs/reiserfs/dir.c --- linux-2.6/fs/reiserfs/dir.c 2007-02-20 14:34:32.000000000 +0800 +++ linux-2.6-lepton/fs/reiserfs/dir.c 2007-04-05 14:35:58.000000000 +0800 @@ -121,6 +121,11 @@ static int reiserfs_readdir(struct file /* it is hidden entry */ continue; d_reclen = entry_length(bh, ih, entry_num); + if (d_reclen < 0) { + pathrelse(&path_to_entry); + ret = -EIO; + goto out; + } d_name = B_I_DEH_ENTRY_FILE_NAME(bh, ih, deh); if (!d_name[d_reclen - 1]) d_reclen = strlen(d_name); O - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/