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CVE Request: Linux: information leak in Rock Ridge Extensions to iso9660 -- fs/isofs/rock.c
From: Salvatore Bonaccorso <carnil () debian org>
Date: Wed, 18 May 2016 10:28:37 +0200
Hi The following commit in Linux v4.6 addresses an information leak caused by not properly handling NM entries containing NUL. Quoting the commit message:
Subject: get_rock_ridge_filename(): handle malformed NM entries Payloads of NM entries are not supposed to contain NUL. When we run into such, only the part prior to the first NUL goes into the concatenation (i.e. the directory entry name being encoded by a bunch of NM entries). We do stop when the amount collected so far + the claimed amount in the current NM entry exceed 254. So far, so good, but what we return as the total length is the sum of *claimed* sizes, not the actual amount collected. And that can grow pretty large - not unlimited, since you'd need to put CE entries in between to be able to get more than the maximum that could be contained in one isofs directory entry / continuation chunk and we are stop once we'd encountered 32 CEs, but you can get about 8Kb easily. And that's what will be passed to readdir callback as the name length. 8Kb __copy_to_user() from a buffer allocated by __get_free_page() Cc: stable () vger kernel org # 0.98pl6+ (yes, really) Signed-off-by: Al Viro <viro () zeniv linux org uk>
Upstream commit: https://git.kernel.org/linus/99d825822eade8d827a1817357cbf3f889a552d6 (v4.6) Can you please assign a CVE for this issue? Regards, Salvatore
Current thread:
- CVE Request: Linux: information leak in Rock Ridge Extensions to iso9660 -- fs/isofs/rock.c Salvatore Bonaccorso (May 18)