We use these services and cookies to improve your user experience. You may opt out if you wish, however, this may limit some features on this site.

Please see our statement on Data Privacy.

Zendesk (Helpdesk and Chat)
Ok

THREATINT
PUBLISHED

CVE-2024-26984

nouveau: fix instmem race condition around ptr stores

Reserved:2024-02-19
Published:2024-05-01
Updated:2024-05-13

Description

In the Linux kernel, the following vulnerability has been resolved: nouveau: fix instmem race condition around ptr stores Running a lot of VK CTS in parallel against nouveau, once every few hours you might see something like this crash. BUG: kernel NULL pointer dereference, address: 0000000000000008 PGD 8000000114e6e067 P4D 8000000114e6e067 PUD 109046067 PMD 0 Oops: 0000 [#1] PREEMPT SMP PTI CPU: 7 PID: 53891 Comm: deqp-vk Not tainted 6.8.0-rc6+ #27 Hardware name: Gigabyte Technology Co., Ltd. Z390 I AORUS PRO WIFI/Z390 I AORUS PRO WIFI-CF, BIOS F8 11/05/2021 RIP: 0010:gp100_vmm_pgt_mem+0xe3/0x180 [nouveau] Code: c7 48 01 c8 49 89 45 58 85 d2 0f 84 95 00 00 00 41 0f b7 46 12 49 8b 7e 08 89 da 42 8d 2c f8 48 8b 47 08 41 83 c7 01 48 89 ee <48> 8b 40 08 ff d0 0f 1f 00 49 8b 7e 08 48 89 d9 48 8d 75 04 48 c1 RSP: 0000:ffffac20c5857838 EFLAGS: 00010202 RAX: 0000000000000000 RBX: 00000000004d8001 RCX: 0000000000000001 RDX: 00000000004d8001 RSI: 00000000000006d8 RDI: ffffa07afe332180 RBP: 00000000000006d8 R08: ffffac20c5857ad0 R09: 0000000000ffff10 R10: 0000000000000001 R11: ffffa07af27e2de0 R12: 000000000000001c R13: ffffac20c5857ad0 R14: ffffa07a96fe9040 R15: 000000000000001c FS: 00007fe395eed7c0(0000) GS:ffffa07e2c980000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000008 CR3: 000000011febe001 CR4: 00000000003706f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: ... ? gp100_vmm_pgt_mem+0xe3/0x180 [nouveau] ? gp100_vmm_pgt_mem+0x37/0x180 [nouveau] nvkm_vmm_iter+0x351/0xa20 [nouveau] ? __pfx_nvkm_vmm_ref_ptes+0x10/0x10 [nouveau] ? __pfx_gp100_vmm_pgt_mem+0x10/0x10 [nouveau] ? __pfx_gp100_vmm_pgt_mem+0x10/0x10 [nouveau] ? __lock_acquire+0x3ed/0x2170 ? __pfx_gp100_vmm_pgt_mem+0x10/0x10 [nouveau] nvkm_vmm_ptes_get_map+0xc2/0x100 [nouveau] ? __pfx_nvkm_vmm_ref_ptes+0x10/0x10 [nouveau] ? __pfx_gp100_vmm_pgt_mem+0x10/0x10 [nouveau] nvkm_vmm_map_locked+0x224/0x3a0 [nouveau] Adding any sort of useful debug usually makes it go away, so I hand wrote the function in a line, and debugged the asm. Every so often pt->memory->ptrs is NULL. This ptrs ptr is set in the nv50_instobj_acquire called from nvkm_kmap. If Thread A and Thread B both get to nv50_instobj_acquire around the same time, and Thread A hits the refcount_set line, and in lockstep thread B succeeds at refcount_inc_not_zero, there is a chance the ptrs value won't have been stored since refcount_set is unordered. Force a memory barrier here, I picked smp_mb, since we want it on all CPUs and it's write followed by a read. v2: use paired smp_rmb/smp_wmb.

Product status

Default status
unaffected

be55287aa5ba before bba8ec5e9b16
affected

be55287aa5ba before 1bc4825d4c3e
affected

be55287aa5ba before 13d76b2f443d
affected

be55287aa5ba before 3ab056814cd8
affected

be55287aa5ba before ad74d208f213
affected

be55287aa5ba before a019b44b1bc6
affected

be55287aa5ba before 21ca9539f093
affected

be55287aa5ba before fff1386cc889
affected

Default status
affected

4.15
affected

Any version before 4.15
unaffected

4.19.313
unaffected

5.4.275
unaffected

5.10.216
unaffected

5.15.157
unaffected

6.1.88
unaffected

6.6.29
unaffected

6.8.8
unaffected

6.9
unaffected

References

https://git.kernel.org/stable/c/bba8ec5e9b16649d85bc9e9086bf7ae5b5716ff9

https://git.kernel.org/stable/c/1bc4825d4c3ec6abe43cf06c3c39d664d044cbf7

https://git.kernel.org/stable/c/13d76b2f443dc371842916dd8768009ff1594716

https://git.kernel.org/stable/c/3ab056814cd8ab84744c9a19ef51360b2271c572

https://git.kernel.org/stable/c/ad74d208f213c06d860916ad40f609ade8c13039

https://git.kernel.org/stable/c/a019b44b1bc6ed224c46fb5f88a8a10dd116e525

https://git.kernel.org/stable/c/21ca9539f09360fd83654f78f2c361f2f5ddcb52

https://git.kernel.org/stable/c/fff1386cc889d8fb4089d285f883f8cba62d82ce

cve.org CVE-2024-26984

nvd.nist.gov CVE-2024-26984

Download JSON

Share this page
https://cve.threatint.com/CVE/CVE-2024-26984