References to Advisories, Solutions, and Tools

By selecting these links, you will be leaving NIST webspace. We have provided these links to other web sites because they may have information that would be of interest to you. No inferences should be drawn on account of other sites being referenced, or not, from this page. There may be other web sites that are more appropriate for your purpose. NIST does not necessarily endorse the views expressed, or concur with the facts presented on these sites. Further, NIST does not endorse any commercial products that may be mentioned on these sites. Please address comments about this page to [email protected].

Change History

In the Linux kernel, the following vulnerability has been resolved:

iomap: fix invalid folio access when i_blkbits differs from I/O granularity

Commit aa35dd5cbc06 ("iomap: fix invalid folio access after
folio_end_read()") partially addressed invalid folio access for folios
without an ifs attached, but it did not handle the case where
1 << inode->i_blkbits matches the folio size but is different from the
granularity used for the IO, which means IO can be submitted for less
than the full folio for the !ifs case.

In this case, the condition:

  if (*bytes_submitted == folio_len)
    ctx->cur_folio = NULL;

in iomap_read_folio_iter() will not invalidate ctx->cur_folio, and
iomap_read_end() will still be called on the folio even though the IO
helper owns it and will finish the read on it.

Fix this by unconditionally invalidating ctx->cur_folio for the !ifs
case.

https://git.kernel.org/stable/c/4a927f670cdb0def226f9f85f42a9f19d9e09c88

https://git.kernel.org/stable/c/bd71fb3fea9945987053968f028a948997cba8cc