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| author | Petr Pavlu <petr.pavlu@suse.com> | 2024-07-17 15:00:23 +0200 |
|---|---|---|
| committer | Kees Cook <kees@kernel.org> | 2024-08-05 14:34:23 -0700 |
| commit | f91f7ac900e7342e0fd66093dfbf7cb8cb585a99 (patch) | |
| tree | 126191748ddf797d75e0ad3582f64b991295f29a /scripts/gcc-plugins/randomize_layout_plugin.c | |
| parent | de9c2c66ad8e787abec7c9d7eff4f8c3cdd28aed (diff) | |
refcount: Report UAF for refcount_sub_and_test(0) when counter==0
When a reference counter is at zero and refcount_sub_and_test() is invoked
to subtract zero, the function accepts this request without any warning and
returns true. This behavior does not seem ideal because the counter being
already at zero indicates a use-after-free. Furthermore, returning true by
refcount_sub_and_test() in this case potentially results in a double-free
done by its caller.
Modify the underlying function __refcount_sub_and_test() to warn about this
case as a use-after-free and have it return false to avoid the potential
double-free.
Signed-off-by: Petr Pavlu <petr.pavlu@suse.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/r/20240717130023.5675-1-petr.pavlu@suse.com
Signed-off-by: Kees Cook <kees@kernel.org>
Diffstat (limited to 'scripts/gcc-plugins/randomize_layout_plugin.c')
0 files changed, 0 insertions, 0 deletions