From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id F12601A76BB for ; Tue, 29 Jul 2025 09:24:43 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1753781084; cv=none; b=SFp5j+e0lyfM0ynNW/IVSpuJmEgMIGw1jnM8gxBwPWtAZH2AkA1mvBnJ1ezFm2iIy3v2RqKyWY97SFqfV5ITos9x7JycnJz2T0HuZaVDsyugKhbtHlSxJc9DhsD7LChahr0NBAHk5JXsEViOBl1B3h2NviSM1xGK2TQJMgZ+gAU= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1753781084; c=relaxed/simple; bh=NfmoRL5vOFPtWo+IZ5Ea7PCg7mu0e/0Soot/YyO332k=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=PMGsvT5dkxs0m5YAnLTFrGdtGMdrVVKf2c/p//4cFXLnSs0TA8u6cSfbQYQUV5d9phiKxBeSw94w9ewtAzNEk3+mRAQZzhgiT0s+50y3kkV/SXChlOunMUv+fhp5xVag4GdUj5tuWc9RS1eD315K2A0zrc6Ab/bg/pWliJR1fWE= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=Q/poAGPm; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="Q/poAGPm" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 55B17C4CEEF; Tue, 29 Jul 2025 09:24:41 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1753781083; bh=NfmoRL5vOFPtWo+IZ5Ea7PCg7mu0e/0Soot/YyO332k=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=Q/poAGPmaOf25zQvClduhiOBFWoLhNeepuPofbBc/VrC9Hox8cSXGwoHYywZ4K1oz QHEMALeA7NI9K9FU9yWjiaqyMGQAywk7jhgS4Z5XH9PbIrdGnHmgxzwiOxoCd6Lkma juxgzoW3ung/PmLsTFkB4KhyZ9D1xihFmDj29HcsWnHHN5oVf/f7o4jbvzeVKAYfiC 9X00YKIWOmAdZcYSWeAs1U2Ec/bMIf9dCJMD4OxLZffz5UacTkm2qg71pyqnT3r6CS FsBrB38SICqvOlD1PN96zY/g0toDtBbVLQ18lSXTX0cCa4BZklsGzcOj2ZLZNgLxvQ 3pTQq+fpefZwg== Date: Tue, 29 Jul 2025 14:54:37 +0530 From: Sumit Garg To: Pei Xiao Cc: jens.wiklander@linaro.org, larper@axis.com, op-tee@lists.trustedfirmware.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] tee: fix NULL pointer dereference in tee_shm_put Message-ID: References: Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: On Wed, Jul 23, 2025 at 10:09:07AM +0800, Pei Xiao wrote: > tee_shm_put have NULL pointer dereference: > > __optee_disable_shm_cache --> > shm = reg_pair_to_ptr(...);//shm maybe return NULL > tee_shm_free(shm); --> > tee_shm_put(shm);//crash > > Add check in tee_shm_put to fix it. > > panic log: > Unable to handle kernel paging request at virtual address 0000000000100cca > Mem abort info: > ESR = 0x0000000096000004 > EC = 0x25: DABT (current EL), IL = 32 bits > SET = 0, FnV = 0 > EA = 0, S1PTW = 0 > FSC = 0x04: level 0 translation fault > Data abort info: > ISV = 0, ISS = 0x00000004, ISS2 = 0x00000000 > CM = 0, WnR = 0, TnD = 0, TagAccess = 0 > GCS = 0, Overlay = 0, DirtyBit = 0, Xs = 0 > user pgtable: 4k pages, 48-bit VAs, pgdp=0000002049d07000 > [0000000000100cca] pgd=0000000000000000, p4d=0000000000000000 > Internal error: Oops: 0000000096000004 [#1] SMP > CPU: 2 PID: 14442 Comm: systemd-sleep Tainted: P OE ------- ---- > 6.6.0-39-generic #38 > Source Version: 938b255f6cb8817c95b0dd5c8c2944acfce94b07 > Hardware name: greatwall GW-001Y1A-FTH, BIOS Great Wall BIOS V3.0 > 10/26/2022 > pstate: 80000005 (Nzcv daif -PAN -UAO -TCO -DIT -SSBS BTYPE=--) > pc : tee_shm_put+0x24/0x188 > lr : tee_shm_free+0x14/0x28 > sp : ffff001f98f9faf0 > x29: ffff001f98f9faf0 x28: ffff0020df543cc0 x27: 0000000000000000 > x26: ffff001f811344a0 x25: ffff8000818dac00 x24: ffff800082d8d048 > x23: ffff001f850fcd18 x22: 0000000000000001 x21: ffff001f98f9fb88 > x20: ffff001f83e76218 x19: ffff001f83e761e0 x18: 000000000000ffff > x17: 303a30303a303030 x16: 0000000000000000 x15: 0000000000000003 > x14: 0000000000000001 x13: 0000000000000000 x12: 0101010101010101 > x11: 0000000000000001 x10: 0000000000000001 x9 : ffff800080e08d0c > x8 : ffff001f98f9fb88 x7 : 0000000000000000 x6 : 0000000000000000 > x5 : 0000000000000000 x4 : 0000000000000000 x3 : 0000000000000000 > x2 : ffff001f83e761e0 x1 : 00000000ffff001f x0 : 0000000000100cca > Call trace: > tee_shm_put+0x24/0x188 > tee_shm_free+0x14/0x28 > __optee_disable_shm_cache+0xa8/0x108 > optee_shutdown+0x28/0x38 > platform_shutdown+0x28/0x40 > device_shutdown+0x144/0x2b0 > kernel_power_off+0x3c/0x80 > hibernate+0x35c/0x388 > state_store+0x64/0x80 > kobj_attr_store+0x14/0x28 > sysfs_kf_write+0x48/0x60 > kernfs_fop_write_iter+0x128/0x1c0 > vfs_write+0x270/0x370 > ksys_write+0x6c/0x100 > __arm64_sys_write+0x20/0x30 > invoke_syscall+0x4c/0x120 > el0_svc_common.constprop.0+0x44/0xf0 > do_el0_svc+0x24/0x38 > el0_svc+0x24/0x88 > el0t_64_sync_handler+0x134/0x150 > el0t_64_sync+0x14c/0x15 > > Fixes: dfd0743f1d9e ("tee: handle lookup of shm with reference count 0") > Signed-off-by: Pei Xiao > --- > drivers/tee/tee_shm.c | 6 +++++- > 1 file changed, 5 insertions(+), 1 deletion(-) Reviewed-by: Sumit Garg -Sumit > > diff --git a/drivers/tee/tee_shm.c b/drivers/tee/tee_shm.c > index daf6e5cfd59a..915239b033f5 100644 > --- a/drivers/tee/tee_shm.c > +++ b/drivers/tee/tee_shm.c > @@ -560,9 +560,13 @@ EXPORT_SYMBOL_GPL(tee_shm_get_from_id); > */ > void tee_shm_put(struct tee_shm *shm) > { > - struct tee_device *teedev = shm->ctx->teedev; > + struct tee_device *teedev; > bool do_release = false; > > + if (!shm || !shm->ctx || !shm->ctx->teedev) > + return; > + > + teedev = shm->ctx->teedev; > mutex_lock(&teedev->mutex); > if (refcount_dec_and_test(&shm->refcount)) { > /* > -- > 2.25.1 >