CVE-2026-46312

What the bug is

vb2_dma_contig sets VMA flags VM_DONTEXPAND and VM_DONTDUMP and I do not see a reason why vb2_dma_sg should behave differently. This avoids hitting `WARN_ON(!(vma->vm_flags & VM_DONTEXPAND));` in drm_gem_mmap_obj() during mmap() of an imported dma-buf from the out of tree Apple ISP camera capture driver which uses vb2_dma_sg_memops. gst-launch-1.0 v4l2src ! gtk4paintablesink [ 38.201528] ------------[ cut here ]------------ [ 38.202135] WARNING: CPU: 7 PID: 2362 at drivers/gpu/drm/drm_gem.c:1144 drm_gem_mmap_obj+0x1f8/0x210 [ 38.203278] Modules linked in: rfcomm snd_seq_dummy snd_hrtimer snd_seq snd_seq_device uinput nf_conntrack_netbios_ns nf_conntrack_broadcast nft_fib_inet nft_fib_ipv4 nft_fib_ipv6 nft_fib nft_reject_inet nf_reject_ipv6 nft_reject nft_ct nft_chain_nat nf_nat nf_conntrack nf_defrag_ipv6 nf_defrag_ipv4 nf_tables qrtr bnep nls_ascii i2c_dev loop fuse dm_multipath nfnetlink brcmfmac_wcc hid_magicmouse hci_bcm4377 brcmfmac brcmutil bluetooth ecdh_generic cfg80211 ecc btrfs xor xor_neon rfkill hid_apple raid6_pq joydev aop_als apple_nvmem_spmi industrialio snd_soc_aop apple_z2 snd_soc_cs42l84 tps6598x snd_soc_tas2764 macsmc_reboot spi_nor macsmc_hwmon rtc_macsmc gpio_macsmc macsmc_power regmap_spmi macsmc_input dockchannel_hid panel_summit appledrm nvme_apple dwc3 snd_soc_macaudio drm_client_lib nvme_core phy_apple_atc hwmon apple_sart apple_dockchannel macsmc apple_rtkit_helper spmi_apple_controller aop apple_wdt mfd_core nvmem_apple_efuses pinctrl_apple_gpio apple_isp apple_dcp videobuf2_dma_sg mux_core spi_apple [ 38.203300] videobuf2_memops i2c_pasemi_platform snd_soc_apple_mca videobuf2_v4l2 videodev clk_apple_nco videobuf2_common snd_pcm_dmaengine adpdrm asahi apple_admac adpdrm_mipi drm_dma_helper pwm_apple i2c_pasemi_core drm_display_helper mc cec apple_dart ofpart apple_soc_cpufreq leds_pwm phram [ 38.217677] CPU: 7 UID: 1000 PID: 2362 Comm: gst-launch-1.0 Tainted: G W 6.17.6+ #asahi-dev PREEMPT(full) [ 38.219040] Tainted: [W]=WARN [ 38.219398] Hardware name: Apple MacBook Pro (13-inch, M2, 2022) (DT) [ 38.220213] pstate: 21400005 (nzCv daif +PAN -UAO -TCO +DIT -SSBS BTYPE=--) [ 38.221088] pc : drm_gem_mmap_obj+0x1f8/0x210 [ 38.221643] lr : drm_gem_mmap_obj+0x78/0x210 [ 38.222178] sp : ffffc0008dc678e0 [ 38.222579] x29: ffffc0008dc678e0 x28: 0000000000042a97 x27: ffff8000b701b480 [ 38.223465] x26: 00000000000000fb x25: ffffc0008dc67d20 x24: ffffc0008dc67968 [ 38.224402] x23: ffff8000e3ca5600 x22: ffff8000265b7800 x21: ffff80003000c0c0 [ 38.225279] x20: 0000000000000000 x19: ffff8000b68c5200 x18: ffffc0008dc67968 [ 38.226151] x17: 0000000000000000 x16: 0000000000000000 x15: ffffc000810a30a8 [ 38.227042] x14: 00007fff637effff x13: 00005555de91ffff x12: 00007fff63293fff [ 38.227942] x11: 0000000000000000 x10: ffff8000184ecf08 x9 : ffffc0007a1900c8 [ 38.228824] x8 : ffffc0008dc67968 x7 : 0000000000000012 x6 : ffffc0015cf1c000 [ 38.229703] x5 : ffffc0008dc676a0 x4 : ffffc00081a27dc0 x3 : 0000000000000038 [ 38.230607] x2 : 0000000000000003 x1 : 0000000000000003 x0 : 00000000100000fb [ 38.231488] Call trace: [ 38.231806] drm_gem_mmap_obj+0x1f8/0x210 (P) [ 38.232342] drm_gem_mmap+0x140/0x260 [ 38.232813] __mmap_region+0x488/0x9a0 [ 38.233277] mmap_region+0xd0/0x148 [ 38.233703] do_mmap+0x350/0x5c0 [ 38.234148] vm_mmap_pgoff+0x14c/0x200 [ 38.234612] ksys_mmap_pgoff+0x150/0x208 [ 38.235107] __arm64_sys_mmap+0x34/0x50 [ 38.235611] invoke_syscall+0x50/0x120 [ 38.236075] el0_svc_common.constprop.0+0x48/0xf0 [ 38.236680] do_el0_svc+0x24/0x38 [ 38.237113] el0_svc+0x38/0x168 [ 38.237507] el0t_64_sync_handler+0xa0/0xe8 [ 38.238034] el0t_64_sync+0x198/0x1a0 [ 38.238491] ---[ end trace 0000000000000000 ]--- There were discussions in [1] at the end of 2023 that mmap() on imported ---truncated---

Where it lives

The fix touches these files. If the subsystem is one you do not use, the practical exposure is lower, though the package is still the vulnerable one.

drivers/media/common/videobuf2/videobuf2-dma-sg.c

What this is

VIDEOBUF2 FRAMEWORKMAINTAINERS section matched on drivers/media/common/videobuf2/* · linux-media@vger.kernel.org · Maintained

Kernel module

videobuf2_dma_sg

Check it on the machine

grep -w CONFIG_VIDEOBUF2_DMA_SG /boot/config-$(uname -r)

Reads the booted kernel's own configuration, on the machine and nowhere else. =y is built in, =m is a module, and an is not set line means the code is not there.

lsmod | grep -w videobuf2_dma_sg

Prints a line if that module is loaded right now, and nothing if it is not. One that is not loaded can still be loaded later by anything that needs it.

Show whether Debian builds this, per release

Debian builds this, but not on every flavour. At least one release below builds the code on some of its kernel flavours and not on others, so the answer depends on the architecture and flavour installed.

• bookworm, trixie, forky, sidMnot built on amd64/cloud-amd64, arm64/cloud-arm64

M

a module where it is built at all; some flavours do not build it

Build switch

CONFIG_VIDEOBUF2_DMA_SG

From the configuration Debian publishes for every kernel flavour it builds. It covers only the architectures Debian ships a linux-config package for, and nothing about a kernel you built yourself. Debian's own status above stays authoritative about the source package.MAINTAINERS kbuild Makefiles Debian linux-config packages

Signals

Published

2026-06-08 (4 months ago)source

CVSS

no vector published, unrated

Attack vector

not published

EPSS

0.11%, higher than 1.4% of all CVEssource

CISA KEV

not listedthe KEV catalogue

Debian urgency

not yet assignedsource

Subsystem

drivers/media

Upstream fixes

The versions the CNA records as introducing and fixing this, and the commit for each. source

Introduced	Fixed in	Commit
2.6.39	6.6.140	feb17524aa4e
2.6.39	6.12.90	1a1360264f69
2.6.39	6.18.32	21fade52ab9f
2.6.39	7.0.9	b4cf91658a63
2.6.39	7.1	7254b31a13aa