CVE-2023-53497

In the Linux kernel, the following vulnerability has been resolved:

media: vsp1: Replace vb2_is_streaming() with vb2_start_streaming_called()

The vsp1 driver uses the vb2_is_streaming() function in its .buf_queue()
handler to check if the .start_streaming() operation has been called,
and decide whether to just add the buffer to an internal queue, or also
trigger a hardware run. vb2_is_streaming() relies on the vb2_queue
structure's streaming field, which used to be set only after calling the
.start_streaming() operation.

Commit a10b21532574 ("media: vb2: add (un)prepare_streaming queue ops")
changed this, setting the .streaming field in vb2_core_streamon() before
enqueuing buffers to the driver and calling .start_streaming(). This
broke the vsp1 driver which now believes that .start_streaming() has
been called when it hasn't, leading to a crash:

[  881.058705] Unable to handle kernel NULL pointer dereference at virtual address 0000000000000020
[  881.067495] Mem abort info:
[  881.070290]   ESR = 0x0000000096000006
[  881.074042]   EC = 0x25: DABT (current EL), IL = 32 bits
[  881.079358]   SET = 0, FnV = 0
[  881.082414]   EA = 0, S1PTW = 0
[  881.085558]   FSC = 0x06: level 2 translation fault
[  881.090439] Data abort info:
[  881.093320]   ISV = 0, ISS = 0x00000006
[  881.097157]   CM = 0, WnR = 0
[  881.100126] user pgtable: 4k pages, 48-bit VAs, pgdp=000000004fa51000
[  881.106573] [0000000000000020] pgd=080000004f36e003, p4d=080000004f36e003, pud=080000004f7ec003, pmd=0000000000000000
[  881.117217] Internal error: Oops: 0000000096000006 [#1] PREEMPT SMP
[  881.123494] Modules linked in: rcar_fdp1 v4l2_mem2mem
[  881.128572] CPU: 0 PID: 1271 Comm: yavta Tainted: G    B              6.2.0-rc1-00023-g6c94e2e99343 #556
[  881.138061] Hardware name: Renesas Salvator-X 2nd version board based on r8a77965 (DT)
[  881.145981] pstate: 400000c5 (nZcv daIF -PAN -UAO -TCO -DIT -SSBS BTYPE=--)
[  881.152951] pc : vsp1_dl_list_add_body+0xa8/0xe0
[  881.157580] lr : vsp1_dl_list_add_body+0x34/0xe0
[  881.162206] sp : ffff80000c267710
[  881.165522] x29: ffff80000c267710 x28: ffff000010938ae8 x27: ffff000013a8dd98
[  881.172683] x26: ffff000010938098 x25: ffff000013a8dc00 x24: ffff000010ed6ba8
[  881.179841] x23: ffff00000faa4000 x22: 0000000000000000 x21: 0000000000000020
[  881.186998] x20: ffff00000faa4000 x19: 0000000000000000 x18: 0000000000000000
[  881.194154] x17: 0000000000000000 x16: 0000000000000000 x15: 0000000000000000
[  881.201309] x14: 0000000000000000 x13: 746e696174206c65 x12: ffff70000157043d
[  881.208465] x11: 1ffff0000157043c x10: ffff70000157043c x9 : dfff800000000000
[  881.215622] x8 : ffff80000ab821e7 x7 : 00008ffffea8fbc4 x6 : 0000000000000001
[  881.222779] x5 : ffff80000ab821e0 x4 : ffff70000157043d x3 : 0000000000000020
[  881.229936] x2 : 0000000000000020 x1 : ffff00000e4f6400 x0 : 0000000000000000
[  881.237092] Call trace:
[  881.239542]  vsp1_dl_list_add_body+0xa8/0xe0
[  881.243822]  vsp1_video_pipeline_run+0x270/0x2a0
[  881.248449]  vsp1_video_buffer_queue+0x1c0/0x1d0
[  881.253076]  __enqueue_in_driver+0xbc/0x260
[  881.257269]  vb2_start_streaming+0x48/0x200
[  881.261461]  vb2_core_streamon+0x13c/0x280
[  881.265565]  vb2_streamon+0x3c/0x90
[  881.269064]  vsp1_video_streamon+0x2fc/0x3e0
[  881.273344]  v4l_streamon+0x50/0x70
[  881.276844]  __video_do_ioctl+0x2bc/0x5d0
[  881.280861]  video_usercopy+0x2a8/0xc80
[  881.284704]  video_ioctl2+0x20/0x40
[  881.288201]  v4l2_ioctl+0xa4/0xc0
[  881.291525]  __arm64_sys_ioctl+0xe8/0x110
[  881.295543]  invoke_syscall+0x68/0x190
[  881.299303]  el0_svc_common.constprop.0+0x88/0x170
[  881.304105]  do_el0_svc+0x4c/0xf0
[  881.307430]  el0_svc+0x4c/0xa0
[  881.310494]  el0t_64_sync_handler+0xbc/0x140
[  881.314773]  el0t_64_sync+0x190/0x194
[  881.318450] Code: d50323bf d65f03c0 91008263 f9800071 (885f7c60)
[  881.324551] ---[ end trace 0000000000000000 ]---
[  881.329173] note: yavta[1271] exited with preempt_count 1

A different r
---truncated---