diff options
| author | Todd Kjos <tkjos@android.com> | 2019-04-24 12:31:18 -0700 |
|---|---|---|
| committer | Todd Kjos <tkjos@google.com> | 2019-06-12 11:27:46 -0700 |
| commit | d97147e5400b4734303487e540e6104afd6a3261 (patch) | |
| tree | 7c83382420e1b8efb58a3953b9325032e2e3fdbc | |
| parent | 28789265bf6ca9bb3afc6c2c6d6942ea860b2e17 (diff) | |
UPSTREAM: binder: check for overflow when alloc for security contextASB-2019-09-05_4.4-p-releaseASB-2019-08-05_4.4-p-releaseASB-2019-07-05_4.4-p-release
commit 0b0509508beff65c1d50541861bc0d4973487dc5 upstream.
When allocating space in the target buffer for the security context,
make sure the extra_buffers_size doesn't overflow. This can only
happen if the given size is invalid, but an overflow can turn it
into a valid size. Fail the transaction if an overflow is detected.
Bug: 130571081
Change-Id: Ibaec652d2073491cc426a4a24004a848348316bf
Signed-off-by: Todd Kjos <tkjos@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -rw-r--r-- | drivers/android/binder.c | 12 |
1 files changed, 11 insertions, 1 deletions
diff --git a/drivers/android/binder.c b/drivers/android/binder.c index ae222e5ad2e2..bd43360458fd 100644 --- a/drivers/android/binder.c +++ b/drivers/android/binder.c @@ -3130,6 +3130,7 @@ static void binder_transaction(struct binder_proc *proc, if (target_node && target_node->txn_security_ctx) { u32 secid; + size_t added_size; security_task_getsecid(proc->tsk, &secid); ret = security_secid_to_secctx(secid, &secctx, &secctx_sz); @@ -3139,7 +3140,15 @@ static void binder_transaction(struct binder_proc *proc, return_error_line = __LINE__; goto err_get_secctx_failed; } - extra_buffers_size += ALIGN(secctx_sz, sizeof(u64)); + added_size = ALIGN(secctx_sz, sizeof(u64)); + extra_buffers_size += added_size; + if (extra_buffers_size < added_size) { + /* integer overflow of extra_buffers_size */ + return_error = BR_FAILED_REPLY; + return_error_param = EINVAL; + return_error_line = __LINE__; + goto err_bad_extra_size; + } } trace_binder_transaction(reply, t, target_node); @@ -3441,6 +3450,7 @@ err_copy_data_failed: t->buffer->transaction = NULL; binder_alloc_free_buf(&target_proc->alloc, t->buffer); err_binder_alloc_buf_failed: +err_bad_extra_size: if (secctx) security_release_secctx(secctx, secctx_sz); err_get_secctx_failed: |