diff options
| author | Carlos Llamas <cmllamas@google.com> | 2022-05-17 18:58:17 +0000 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2022-05-19 18:41:26 +0200 |
| commit | dafa5e9ab8b5b31d64c0ded188d95f8bb6be9746 (patch) | |
| tree | e858cd584328605834333c3d898e6d8971119720 /drivers/android | |
| parent | da4864962d768b33e3bc31cd233270af6226686d (diff) | |
| download | linux-dafa5e9ab8b5b31d64c0ded188d95f8bb6be9746.tar.gz | |
binder: fix potential UAF of target_{proc,thread}
Commit 9474be34a727 ("binder: add failed transaction logging info")
dereferences target_{proc,thread} after they have been potentially
freed by binder_proc_dec_tmpref() and binder_thread_dec_tmpref().
This patch delays the release of the two references after their last
usage. Fixes the following two errors reported by smatch:
drivers/android/binder.c:3562 binder_transaction() error: dereferencing freed memory 'target_proc'
drivers/android/binder.c:3563 binder_transaction() error: dereferencing freed memory 'target_thread'
Fixes: 9474be34a727 ("binder: add failed transaction logging info")
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Acked-by: Todd Kjos <tkjos@google.com>
Signed-off-by: Carlos Llamas <cmllamas@google.com>
Link: https://lore.kernel.org/r/20220517185817.598872-1-cmllamas@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/android')
| -rw-r--r-- | drivers/android/binder.c | 9 |
1 files changed, 5 insertions, 4 deletions
diff --git a/drivers/android/binder.c b/drivers/android/binder.c index 176bb0463680..9e36608eac6c 100644 --- a/drivers/android/binder.c +++ b/drivers/android/binder.c @@ -3546,10 +3546,6 @@ err_bad_call_stack: err_empty_call_stack: err_dead_binder: err_invalid_target_handle: - if (target_thread) - binder_thread_dec_tmpref(target_thread); - if (target_proc) - binder_proc_dec_tmpref(target_proc); if (target_node) { binder_dec_node(target_node, 1, 0); binder_dec_node_tmpref(target_node); @@ -3565,6 +3561,11 @@ err_invalid_target_handle: (u64)tr->data_size, (u64)tr->offsets_size, return_error_line); + if (target_thread) + binder_thread_dec_tmpref(target_thread); + if (target_proc) + binder_proc_dec_tmpref(target_proc); + { struct binder_transaction_log_entry *fe; |