CVE-2021-47531
published 2024-05-24CVE-2021-47531: In the Linux kernel, the following vulnerability has been resolved: drm/msm: Fix mmap to include VM_IO and VM_DONTDUMP In commit 510410bfc034 ("drm/msm…
PriorityP421medium5.5CVSS 3.1
AVLACLPRLUINSUCNINAH
EPSS
0.21%
10.7th percentile
In the Linux kernel, the following vulnerability has been resolved:
drm/msm: Fix mmap to include VM_IO and VM_DONTDUMP
In commit 510410bfc034 ("drm/msm: Implement mmap as GEM object
function") we switched to a new/cleaner method of doing things. That's
good, but we missed a little bit.
Before that commit, we used to _first_ run through the
drm_gem_mmap_obj() case where `obj->funcs->mmap()` was NULL. That meant
that we ran:
vma->vm_flags |= VM_IO | VM_PFNMAP | VM_DONTEXPAND | VM_DONTDUMP;
vma->vm_page_prot = pgprot_writecombine(vm_get_page_prot(vma->vm_flags));
vma->vm_page_prot = pgprot_decrypted(vma->vm_page_prot);
...and _then_ we modified those mappings with our own. Now that
`obj->funcs->mmap()` is no longer NULL we don't run the default
code. It looks like the fact that the vm_flags got VM_IO / VM_DONTDUMP
was important because we're now getting crashes on Chromebooks that
use ARC++ while logging out. Specifically a crash that looks like this
(this is on a 5.10 kernel w/ relevant backports but also seen on a
5.15 kernel):
Unable to handle kernel paging request at virtual address ffffffc008000000
Mem abort info:
ESR = 0x96000006
EC = 0x25: DABT (current EL), IL = 32 bits
SET = 0, FnV = 0
EA = 0, S1PTW = 0
Data abort info:
ISV = 0, ISS = 0x00000006
CM = 0, WnR = 0
swapper pgtable: 4k pages, 39-bit VAs, pgdp=000000008293d000
[ffffffc008000000] pgd=00000001002b3003, p4d=00000001002b3003,
pud=00000001002b3003, pmd=0000000000000000
Internal error: Oops: 96000006 [#1] PREEMPT SMP
[...]
CPU: 7 PID: 15734 Comm: crash_dump64 Tainted: G W 5.10.67 #1 [...]
Hardware name: Qualcomm Technologies, Inc. sc7280 IDP SKU2 platform (DT)
pstate: 80400009 (Nzcv daif +PAN -UAO -TCO BTYPE=--)
pc : __arch_copy_to_user+0xc0/0x30c
lr : copyout+0xac/0x14c
[...]
Call trace:
__arch_copy_to_user+0xc0/0x30c
copy_page_to_iter+0x1a0/0x294
process_vm_rw_core+0x240/0x408
process_vm_rw+0x110/0x16c
__arm64_sys_process_vm_readv+0x30/0x3c
el0_svc_common+0xf8/0x250
do_el0_svc+0x30/0x80
el0_svc+0x
Affected
9 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| debian | linux | < linux 5.15.15-1 (bookworm) | linux 5.15.15-1 (bookworm) |
| linux | linux | — | — |
| linux | linux | >= 510410bfc034c57cc3caf1572aa47c1017bab2f9 < 8e2b7fe5e8a4be5e571561d9afcfbd92097288ba | 8e2b7fe5e8a4be5e571561d9afcfbd92097288ba |
| linux | linux | >= 510410bfc034c57cc3caf1572aa47c1017bab2f9 < 3466d9e217b337bf473ee629c608e53f9f3ab786 | 3466d9e217b337bf473ee629c608e53f9f3ab786 |
| linux | linux_kernel | — | — |
| linux | linux_kernel | >= 0 < 5.15.15-1 | 5.15.15-1 |
| linux | linux_kernel | >= 0 < 5.15.15-1 | 5.15.15-1 |
| linux | linux_kernel | >= 0 < 5.15.15-1 | 5.15.15-1 |
| linux | linux_kernel | >= 5.15 < 5.15.7 | 5.15.7 |
CVSS provenance
nvdv3.15.5MEDIUMCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
osv5.5MEDIUM
vendor_debian5.5MEDIUM
vendor_redhat5.5MEDIUM
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Red Hat
kernel: drm/msm: Fix mmap to include VM_IO and VM_DONTDUMP
vendor_redhat·2024-05-24·CVSS 5.5
CVE-2021-47531 [MEDIUM] CWE-824 kernel: drm/msm: Fix mmap to include VM_IO and VM_DONTDUMP
kernel: drm/msm: Fix mmap to include VM_IO and VM_DONTDUMP
In the Linux kernel, the following vulnerability has been resolved:
drm/msm: Fix mmap to include VM_IO and VM_DONTDUMP
In commit 510410bfc034 ("drm/msm: Implement mmap as GEM object
function") we switched to a new/cleaner method of doing things. That's
good, but we missed a little bit.
Before that commit, we used to _first_ run through the
drm_gem_mmap_obj() case where `obj->funcs->mmap()` was NULL. That meant
that we ran:
vma->vm_flags |= VM_IO | VM_PFNMAP | VM_DONTEXPAND | VM_DONTDUMP;
vma->vm_page_prot = pgprot_writecombine(vm_get_page_prot(vma->vm_flags));
vma->vm_page_prot = pgprot_decrypted(vma->vm_page_prot);
...and _then_ we modified those mappings with our own. Now that
`obj->funcs->mmap()` is no longer NULL we don't run
Debian
CVE-2021-47531: linux - In the Linux kernel, the following vulnerability has been resolved: drm/msm: Fi...
vendor_debian·2021·CVSS 5.5
CVE-2021-47531 [MEDIUM] CVE-2021-47531: linux - In the Linux kernel, the following vulnerability has been resolved: drm/msm: Fi...
In the Linux kernel, the following vulnerability has been resolved: drm/msm: Fix mmap to include VM_IO and VM_DONTDUMP In commit 510410bfc034 ("drm/msm: Implement mmap as GEM object function") we switched to a new/cleaner method of doing things. That's good, but we missed a little bit. Before that commit, we used to _first_ run through the drm_gem_mmap_obj() case where `obj->funcs->mmap()` was NULL. That meant that we ran: vma->vm_flags |= VM_IO | VM_PFNMAP | VM_DONTEXPAND | VM_DONTDUMP; vma->vm_page_prot = pgprot_writecombine(vm_get_page_prot(vma->vm_flags)); vma->vm_page_prot = pgprot_decrypted(vma->vm_page_prot); ...and _then_ we modified those mappings with our own. Now that `obj->funcs->mmap()` is no longer NULL we don't run the default code. It looks like the fact that the vm_flags g
OSV
CVE-2021-47531: In the Linux kernel, the following vulnerability has been resolved: drm/msm: Fix mmap to include VM_IO and VM_DONTDUMP In commit 510410bfc034 ("drm/ms
osv·2024-05-24·CVSS 5.5
CVE-2021-47531 [MEDIUM] CVE-2021-47531: In the Linux kernel, the following vulnerability has been resolved: drm/msm: Fix mmap to include VM_IO and VM_DONTDUMP In commit 510410bfc034 ("drm/ms
In the Linux kernel, the following vulnerability has been resolved: drm/msm: Fix mmap to include VM_IO and VM_DONTDUMP In commit 510410bfc034 ("drm/msm: Implement mmap as GEM object function") we switched to a new/cleaner method of doing things. That's good, but we missed a little bit. Before that commit, we used to _first_ run through the drm_gem_mmap_obj() case where `obj->funcs->mmap()` was NULL. That meant that we ran: vma->vm_flags |= VM_IO | VM_PFNMAP | VM_DONTEXPAND | VM_DONTDUMP; vma->vm_page_prot = pgprot_writecombine(vm_get_page_prot(vma->vm_flags)); vma->vm_page_prot = pgprot_decrypted(vma->vm_page_prot); ...and _then_ we modified those mappings with our own. Now that `obj->funcs->mmap()` is no longer NULL we don't run the default code. It looks like the fact that the vm_flags g
No detection rules found.
No public exploits indexed.
2024-05-24
Published