CVE-2021-47566
published 2024-05-24CVE-2021-47566: In the Linux kernel, the following vulnerability has been resolved: proc/vmcore: fix clearing user buffer by properly using clear_user() To clear a user buffer…
PriorityP341high7.8CVSS 3.1
AVLACLPRLUINSUCHIHAH
EPSS
0.23%
13.7th percentile
In the Linux kernel, the following vulnerability has been resolved:
proc/vmcore: fix clearing user buffer by properly using clear_user()
To clear a user buffer we cannot simply use memset, we have to use
clear_user(). With a virtio-mem device that registers a vmcore_cb and
has some logically unplugged memory inside an added Linux memory block,
I can easily trigger a BUG by copying the vmcore via "cp":
systemd[1]: Starting Kdump Vmcore Save Service...
kdump[420]: Kdump is using the default log level(3).
kdump[453]: saving to /sysroot/var/crash/127.0.0.1-2021-11-11-14:59:22/
kdump[458]: saving vmcore-dmesg.txt to /sysroot/var/crash/127.0.0.1-2021-11-11-14:59:22/
kdump[465]: saving vmcore-dmesg.txt complete
kdump[467]: saving vmcore
BUG: unable to handle page fault for address: 00007f2374e01000
#PF: supervisor write access in kernel mode
#PF: error_code(0x0003) - permissions violation
PGD 7a523067 P4D 7a523067 PUD 7a528067 PMD 7a525067 PTE 800000007048f867
Oops: 0003 [#1] PREEMPT SMP NOPTI
CPU: 0 PID: 468 Comm: cp Not tainted 5.15.0+ #6
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.14.0-27-g64f37cc530f1-prebuilt.qemu.org 04/01/2014
RIP: 0010:read_from_oldmem.part.0.cold+0x1d/0x86
Code: ff ff ff e8 05 ff fe ff e9 b9 e9 7f ff 48 89 de 48 c7 c7 38 3b 60 82 e8 f1 fe fe ff 83 fd 08 72 3c 49 8d 7d 08 4c 89 e9 89 e8 c7 45 00 00 00 00 00 49 c7 44 05 f8 00 00 00 00 48 83 e7 f81
RSP: 0018:ffffc9000073be08 EFLAGS: 00010212
RAX: 0000000000001000 RBX: 00000000002fd000 RCX: 00007f2374e01000
RDX: 0000000000000001 RSI: 00000000ffffdfff RDI: 00007f2374e01008
RBP: 0000000000001000 R08: 0000000000000000 R09: ffffc9000073bc50
R10: ffffc9000073bc48 R11: ffffffff829461a8 R12: 000000000000f000
R13: 00007f2374e01000 R14: 0000000000000000 R15: ffff88807bd421e8
FS: 00007f2374e12140(0000) GS:ffff88807f000000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f2374e01000 CR3: 000000007a4aa000 CR4: 0000000000350eb0
Call Trace:
read_vmcore+0x
Affected
22 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 | >= 997c136f518c5debd63847e78e2a8694f56dcf90 < a9e164bd160be8cbee1df70acb379129e3cd2e7c | a9e164bd160be8cbee1df70acb379129e3cd2e7c |
| linux | linux | >= 997c136f518c5debd63847e78e2a8694f56dcf90 < 33a7d698f30fa0b99d50569e9909d3baa65d8f6a | 33a7d698f30fa0b99d50569e9909d3baa65d8f6a |
| linux | linux | >= 997c136f518c5debd63847e78e2a8694f56dcf90 < 99d348b82bcb36171f24411d3f1a15706a2a937a | 99d348b82bcb36171f24411d3f1a15706a2a937a |
| linux | linux | >= 997c136f518c5debd63847e78e2a8694f56dcf90 < 9ef384ed300d1bcfb23d0ab0b487d544444d4b52 | 9ef384ed300d1bcfb23d0ab0b487d544444d4b52 |
| linux | linux | >= 997c136f518c5debd63847e78e2a8694f56dcf90 < fd7974c547abfb03072a4ee706d3a6f182266f89 | fd7974c547abfb03072a4ee706d3a6f182266f89 |
| linux | linux | >= 997c136f518c5debd63847e78e2a8694f56dcf90 < a8a917058faf4abaec9fb614bb6d5f8fe3529ec6 | a8a917058faf4abaec9fb614bb6d5f8fe3529ec6 |
| linux | linux | >= 997c136f518c5debd63847e78e2a8694f56dcf90 < 7b3a34f08d11e7f05cd00b8e09adaa15192f0ad1 | 7b3a34f08d11e7f05cd00b8e09adaa15192f0ad1 |
| linux | linux | >= 997c136f518c5debd63847e78e2a8694f56dcf90 < c1e63117711977cc4295b2ce73de29dd17066c82 | c1e63117711977cc4295b2ce73de29dd17066c82 |
| linux | linux_kernel | — | — |
| linux | linux_kernel | >= 0 < 5.10.84-1 | 5.10.84-1 |
| 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 | >= 0 < 5.15.15-1 | 5.15.15-1 |
| linux | linux_kernel | >= 3.0 < 4.4.294 | 4.4.294 |
| linux | linux_kernel | >= 4.10 < 4.14.257 | 4.14.257 |
| linux | linux_kernel | >= 4.15 < 4.19.219 | 4.19.219 |
| linux | linux_kernel | >= 4.20 < 5.4.163 | 5.4.163 |
| linux | linux_kernel | >= 4.5 < 4.9.292 | 4.9.292 |
| linux | linux_kernel | >= 5.11 < 5.15.6 | 5.15.6 |
| linux | linux_kernel | >= 5.5 < 5.10.83 | 5.10.83 |
CVSS provenance
nvdv3.17.8HIGHCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
osv7.8HIGH
vendor_debian7.8HIGH
vendor_redhat7.8HIGH
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OSV
CVE-2021-47566: In the Linux kernel, the following vulnerability has been resolved: proc/vmcore: fix clearing user buffer by properly using clear_user() To clear a us
osv·2024-05-24·CVSS 7.8
CVE-2021-47566 [HIGH] CVE-2021-47566: In the Linux kernel, the following vulnerability has been resolved: proc/vmcore: fix clearing user buffer by properly using clear_user() To clear a us
In the Linux kernel, the following vulnerability has been resolved: proc/vmcore: fix clearing user buffer by properly using clear_user() To clear a user buffer we cannot simply use memset, we have to use clear_user(). With a virtio-mem device that registers a vmcore_cb and has some logically unplugged memory inside an added Linux memory block, I can easily trigger a BUG by copying the vmcore via "cp": systemd[1]: Starting Kdump Vmcore Save Service... kdump[420]: Kdump is using the default log level(3). kdump[453]: saving to /sysroot/var/crash/127.0.0.1-2021-11-11-14:59:22/ kdump[458]: saving vmcore-dmesg.txt to /sysroot/var/crash/127.0.0.1-2021-11-11-14:59:22/ kdump[465]: saving vmcore-dmesg.txt complete kdump[467]: saving vmcore BUG: unable to handle page fault for address: 00007f2374e010
Red Hat
kernel: proc/vmcore: fix clearing user buffer by properly using clear_user()
vendor_redhat·2024-05-24·CVSS 7.8
CVE-2021-47566 [HIGH] CWE-501 kernel: proc/vmcore: fix clearing user buffer by properly using clear_user()
kernel: proc/vmcore: fix clearing user buffer by properly using clear_user()
In the Linux kernel, the following vulnerability has been resolved:
proc/vmcore: fix clearing user buffer by properly using clear_user()
To clear a user buffer we cannot simply use memset, we have to use
clear_user(). With a virtio-mem device that registers a vmcore_cb and
has some logically unplugged memory inside an added Linux memory block,
I can easily trigger a BUG by copying the vmcore via "cp":
systemd[1]: Starting Kdump Vmcore Save Service...
kdump[420]: Kdump is using the default log level(3).
kdump[453]: saving to /sysroot/var/crash/127.0.0.1-2021-11-11-14:59:22/
kdump[458]: saving vmcore-dmesg.txt to /sysroot/var/crash/127.0.0.1-2021-11-11-14:59:22/
kdump[465]: saving vmcore-dmesg.txt complete
kdump[46
Debian
CVE-2021-47566: linux - In the Linux kernel, the following vulnerability has been resolved: proc/vmcore...
vendor_debian·2021·CVSS 7.8
CVE-2021-47566 [HIGH] CVE-2021-47566: linux - In the Linux kernel, the following vulnerability has been resolved: proc/vmcore...
In the Linux kernel, the following vulnerability has been resolved: proc/vmcore: fix clearing user buffer by properly using clear_user() To clear a user buffer we cannot simply use memset, we have to use clear_user(). With a virtio-mem device that registers a vmcore_cb and has some logically unplugged memory inside an added Linux memory block, I can easily trigger a BUG by copying the vmcore via "cp": systemd[1]: Starting Kdump Vmcore Save Service... kdump[420]: Kdump is using the default log level(3). kdump[453]: saving to /sysroot/var/crash/127.0.0.1-2021-11-11-14:59:22/ kdump[458]: saving vmcore-dmesg.txt to /sysroot/var/crash/127.0.0.1-2021-11-11-14:59:22/ kdump[465]: saving vmcore-dmesg.txt complete kdump[467]: saving vmcore BUG: unable to handle page fault for address: 00007f2374e010
No detection rules found.
No public exploits indexed.
https://git.kernel.org/stable/c/33a7d698f30fa0b99d50569e9909d3baa65d8f6ahttps://git.kernel.org/stable/c/7b3a34f08d11e7f05cd00b8e09adaa15192f0ad1https://git.kernel.org/stable/c/99d348b82bcb36171f24411d3f1a15706a2a937ahttps://git.kernel.org/stable/c/9ef384ed300d1bcfb23d0ab0b487d544444d4b52https://git.kernel.org/stable/c/a8a917058faf4abaec9fb614bb6d5f8fe3529ec6https://git.kernel.org/stable/c/a9e164bd160be8cbee1df70acb379129e3cd2e7chttps://git.kernel.org/stable/c/c1e63117711977cc4295b2ce73de29dd17066c82https://git.kernel.org/stable/c/fd7974c547abfb03072a4ee706d3a6f182266f89https://git.kernel.org/stable/c/33a7d698f30fa0b99d50569e9909d3baa65d8f6ahttps://git.kernel.org/stable/c/7b3a34f08d11e7f05cd00b8e09adaa15192f0ad1https://git.kernel.org/stable/c/99d348b82bcb36171f24411d3f1a15706a2a937ahttps://git.kernel.org/stable/c/9ef384ed300d1bcfb23d0ab0b487d544444d4b52https://git.kernel.org/stable/c/a8a917058faf4abaec9fb614bb6d5f8fe3529ec6https://git.kernel.org/stable/c/a9e164bd160be8cbee1df70acb379129e3cd2e7chttps://git.kernel.org/stable/c/c1e63117711977cc4295b2ce73de29dd17066c82https://git.kernel.org/stable/c/fd7974c547abfb03072a4ee706d3a6f182266f89
2024-05-24
Published