linux-stable/fs/pstore
Kees Cook e163fdb3f7 pstore/ram: Regularize prz label allocation lifetime
In my attempt to fix a memory leak, I introduced a double-free in the
pstore error path. Instead of trying to manage the allocation lifetime
between persistent_ram_new() and its callers, adjust the logic so
persistent_ram_new() always takes a kstrdup() copy, and leaves the
caller's allocation lifetime up to the caller. Therefore callers are
_always_ responsible for freeing their label. Before, it only needed
freeing when the prz itself failed to allocate, and not in any of the
other prz failure cases, which callers would have no visibility into,
which is the root design problem that lead to both the leak and now
double-free bugs.

Reported-by: Cengiz Can <cengiz@kernel.wtf>
Link: https://lore.kernel.org/lkml/d4ec59002ede4aaf9928c7f7526da87c@kernel.wtf
Fixes: 8df955a32a ("pstore/ram: Fix error-path memory leak in persistent_ram_new() callers")
Cc: stable@vger.kernel.org
Signed-off-by: Kees Cook <keescook@chromium.org>
2020-01-08 17:05:45 -08:00
..
ftrace.c pstore: no need to check return value of debugfs_create functions 2019-07-08 21:04:42 -07:00
inode.c pstore: Fix double-free in pstore_mkfile() failure path 2019-07-08 21:04:42 -07:00
internal.h pstore: Centralize init/exit routines 2018-10-22 07:11:58 -07:00
Kconfig treewide: Add SPDX license identifier - Makefile/Kconfig 2019-05-21 10:50:46 +02:00
Makefile License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
platform.c pstore: Make pstore_choose_compression() static 2019-10-29 09:43:03 -07:00
pmsg.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 282 2019-06-05 17:36:37 +02:00
ram.c pstore/ram: Regularize prz label allocation lifetime 2020-01-08 17:05:45 -08:00
ram_core.c pstore/ram: Regularize prz label allocation lifetime 2020-01-08 17:05:45 -08:00