saving data "stored" in badblocks

Did you: -- run badblocks correctly -- run e2fsck -c or e2fsck -cc -- confirm disk health state with smartd (smartmontools) -- test disk with maker's hd utils?

First, do you know that they do contain data?

$ badblocks will (IIRC) mark blocks bad precisely because it cannot read from them. How will you read the data?

If you are prepared to do some really down-n-dirty work to retreive whatever parts you can, you can take a look at this for some idea what sort of fun you're looking at:

You probably also want to run any test-repair utilities offered for your hard drive. You may locate one here:

Some of the Linux disk rescue CDs have recovery utils on them, but I've been very lucky and not had to try them out -- so can't really recommend one. When I've been bitten I've had backups (or did not mind data loss) and just built a new fs and restored my files.

And if really desperate (and can't afford commercial recovery services) you can use a hard disk editor. This one is simple, powerful, free, and very easy to mishandle (!) and "destroy" your whole disk (be warned):

Be sure not to force writes-relocations of the bad sectors-blocks till you have recovered as much data as possible.

Hopefully, someone else will offer something less tedious and fairly reliable. If not you'll have to decide how much work-$ recovery is worth. You will most likely lose at least some disk sector(s) (512 bytes) but perhaps not entire blocks.

hth, prg