cbcvebase.
CVE-2022-49526
published 2025-02-26

CVE-2022-49526: In the Linux kernel, the following vulnerability has been resolved: md/bitmap: don't set sb values if can't pass sanity check If bitmap area contains invalid…

PriorityP420medium5.5CVSS 3.1
AVLACLPRLUINSUCNINAH
EPSS
0.32%
24.2th percentile
In the Linux kernel, the following vulnerability has been resolved: md/bitmap: don't set sb values if can't pass sanity check If bitmap area contains invalid data, kernel will crash then mdadm triggers "Segmentation fault". This is cluster-md speical bug. In non-clustered env, mdadm will handle broken metadata case. In clustered array, only kernel space handles bitmap slot info. But even this bug only happened in clustered env, current sanity check is wrong, the code should be changed. How to trigger: (faulty injection) dd if=/dev/zero bs=1M count=1 oflag=direct of=/dev/sda dd if=/dev/zero bs=1M count=1 oflag=direct of=/dev/sdb mdadm -C /dev/md0 -b clustered -e 1.2 -n 2 -l mirror /dev/sda /dev/sdb mdadm -Ss echo aaa > magic.txt == below modifying slot 2 bitmap data == dd if=magic.txt of=/dev/sda seek=16384 bs=1 count=3 <== destroy magic dd if=/dev/zero of=/dev/sda seek=16436 bs=1 count=4 <== ZERO chunksize mdadm -A /dev/md0 /dev/sda /dev/sdb == kernel crashes. mdadm outputs "Segmentation fault" == Reason of kernel crash: In md_bitmap_read_sb (called by md_bitmap_create), bad bitmap magic didn't block chunksize assignment, and zero value made DIV_ROUND_UP_SECTOR_T() trigger "divide error". Crash log: kernel: md: md0 stopped. kernel: md/raid1:md0: not clean -- starting background reconstruction kernel: md/raid1:md0: active with 2 out of 2 mirrors kernel: dlm: ... ... kernel: md-cluster: Joined cluster 44810aba-38bb-e6b8-daca-bc97a0b254aa slot 1 kernel: md0: invalid bitmap file superblock: bad magic kernel: md_bitmap_copy_from_slot can't get bitmap from slot 2 kernel: md-cluster: Could not gather bitmaps from slot 2 kernel: divide error: 0000 [#1] SMP NOPTI kernel: CPU: 0 PID: 1603 Comm: mdadm Not tainted 5.14.6-1-default kernel: Hardware name: QEMU Standard PC (i440FX + PIIX, 1996) kernel: RIP: 0010:md_bitmap_create+0x1d1/0x850 [md_mod] kernel: RSP: 0018:ffffc22ac0843ba0 EFLAGS: 00010246 kernel: ... ... kernel: Call Trace: kernel: ? dlm_lock_sync+0xd0/0xd0 [md

Affected

19 ranges
VendorProductVersion rangeFixed in
debianlinux< linux 5.18.5-1 (bookworm)linux 5.18.5-1 (bookworm)
linuxlinux
linuxlinux>= ef99bf480de9bde9d3b2afdf05324670fab4e571 < 422e8f7ba1e08c8e0e88d375bcb550bc2bbfe96d422e8f7ba1e08c8e0e88d375bcb550bc2bbfe96d
linuxlinux>= ef99bf480de9bde9d3b2afdf05324670fab4e571 < 0959aa00f9765bd8c654b1365012e41b51c733cc0959aa00f9765bd8c654b1365012e41b51c733cc
linuxlinux>= ef99bf480de9bde9d3b2afdf05324670fab4e571 < e69e93120f6219b9cc4fba3b515b6ababd8548aae69e93120f6219b9cc4fba3b515b6ababd8548aa
linuxlinux>= ef99bf480de9bde9d3b2afdf05324670fab4e571 < 27f672af28a8e9b783ff7f0eaf7ef2fbd5a2f4ba27f672af28a8e9b783ff7f0eaf7ef2fbd5a2f4ba
linuxlinux>= ef99bf480de9bde9d3b2afdf05324670fab4e571 < cf9392282a2cf5a8d83dd1c5aa1a097e12f172bccf9392282a2cf5a8d83dd1c5aa1a097e12f172bc
linuxlinux>= ef99bf480de9bde9d3b2afdf05324670fab4e571 < d8f1558e1daf54f53a90b4c5700ae3e3a4b13412d8f1558e1daf54f53a90b4c5700ae3e3a4b13412
linuxlinux>= ef99bf480de9bde9d3b2afdf05324670fab4e571 < e68cb83a57a458b01c9739e2ad9cb70b04d1e6d2e68cb83a57a458b01c9739e2ad9cb70b04d1e6d2
linuxlinux_kernel< 4.19.2474.19.247
linuxlinux_kernel>= 0 < 5.10.127-15.10.127-1
linuxlinux_kernel>= 0 < 5.18.5-15.18.5-1
linuxlinux_kernel>= 0 < 5.18.5-15.18.5-1
linuxlinux_kernel>= 0 < 5.18.5-15.18.5-1
linuxlinux_kernel>= 4.20 < 5.4.1985.4.198
linuxlinux_kernel>= 5.11 < 5.15.465.15.46
linuxlinux_kernel>= 5.16 < 5.17.145.17.14
linuxlinux_kernel>= 5.18 < 5.18.35.18.3
linuxlinux_kernel>= 5.5 < 5.10.1215.10.121

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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