cbcvebase.
CVE-2024-41067
published 2024-07-29

CVE-2024-41067: In the Linux kernel, the following vulnerability has been resolved: btrfs: scrub: handle RST lookup error correctly [BUG] When running btrfs/060 with forced…

PriorityP419medium5.5CVSS 3.1
AVLACLPRLUINSUCNINAH
EPSS
0.20%
9.7th percentile
In the Linux kernel, the following vulnerability has been resolved: btrfs: scrub: handle RST lookup error correctly [BUG] When running btrfs/060 with forced RST feature, it would crash the following ASSERT() inside scrub_read_endio(): ASSERT(sector_nr nr_sectors); Before that, we would have tree dump from btrfs_get_raid_extent_offset(), as we failed to find the RST entry for the range. [CAUSE] Inside scrub_submit_extent_sector_read() every time we allocated a new bbio we immediately called btrfs_map_block() to make sure there was some RST range covering the scrub target. But if btrfs_map_block() fails, we immediately call endio for the bbio, while the bbio is newly allocated, it's completely empty. Then inside scrub_read_endio(), we go through the bvecs to find the sector number (as bi_sector is no longer reliable if the bio is submitted to lower layers). And since the bio is empty, such bvecs iteration would not find any sector matching the sector, and return sector_nr == stripe->nr_sectors, triggering the ASSERT(). [FIX] Instead of calling btrfs_map_block() after allocating a new bbio, call btrfs_map_block() first. Since our only objective of calling btrfs_map_block() is only to update stripe_len, there is really no need to do that after btrfs_alloc_bio(). This new timing would avoid the problem of handling empty bbio completely, and in fact fixes a possible race window for the old code, where if the submission thread is the only owner of the pending_io, the scrub would never finish (since we didn't decrease the pending_io counter). Although the root cause of RST lookup failure still needs to be addressed.

Affected

22 ranges
VendorProductVersion rangeFixed in
debianlinux< linux 6.9.11-1 (forky)linux 6.9.11-1 (forky)
linuxlinux
linuxlinux>= 9acaa64187f9b4cbb75622883c96ea1a893d5431 < 17d1fd302a53d7e456a7412da74be74a0cf63a7217d1fd302a53d7e456a7412da74be74a0cf63a72
linuxlinux>= 9acaa64187f9b4cbb75622883c96ea1a893d5431 < 2c49908634a2b97b1c3abe0589be2739ac5e7fd52c49908634a2b97b1c3abe0589be2739ac5e7fd5
linuxlinux_kernel< 6.9.116.9.11
linuxlinux_kernel
linuxlinux_kernel>= 0 < 6.9.11-16.9.11-1
linuxlinux_kernel>= 0 < 6.9.11-16.9.11-1
linuxlinux_kernel>= 0 < 6.8.0-48.486.8.0-48.48
msrcazl3_kernel_6.6.104.2-4_on_azure_linux_3.0
msrcazl3_kernel_6.6.112.1-2_on_azure_linux_3.0
msrcazl3_kernel_6.6.117.1-1_on_azure_linux_3.0
msrcazl3_kernel_6.6.119.3-1_on_azure_linux_3.0
msrcazl3_kernel_6.6.119.3-3_on_azure_linux_3.0
msrcazl3_kernel_6.6.121.1-1_on_azure_linux_3.0
msrcazl3_kernel_6.6.126.1-1_on_azure_linux_3.0
msrcazl3_kernel_6.6.130.1-3_on_azure_linux_3.0
msrcazl3_kernel_6.6.96.2-1_on_azure_linux_3.0
msrcazl3_kernel_6.6.96.2-2_on_azure_linux_3.0
msrccbl2_kernel_5.15.186.1-1_on_cbl_mariner_2.0
msrccbl2_kernel_5.15.200.1-1_on_cbl_mariner_2.0
msrccbl2_kernel_5.15.202.1-1_on_cbl_mariner_2.0

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_debian5.5LOW
vendor_redhat5.5MEDIUM
vendor_ubuntu5.5MEDIUM
vendor_msrc4.7MEDIUM
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