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CVE-2023-53813— ext4: fix rbtree traversal bug in ext4_mb_use_preallocated

EPSS 0.03% · P8
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I. Basic Information for CVE-2023-53813

Vulnerability Information
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Vulnerability Title
ext4: fix rbtree traversal bug in ext4_mb_use_preallocated
Source: NVD (National Vulnerability Database)
Vulnerability Description
In the Linux kernel, the following vulnerability has been resolved: ext4: fix rbtree traversal bug in ext4_mb_use_preallocated During allocations, while looking for preallocations(PA) in the per inode rbtree, we can't do a direct traversal of the tree because ext4_mb_discard_group_preallocation() can paralelly mark the pa deleted and that can cause direct traversal to skip some entries. This was leading to a BUG_ON() being hit [1] when we missed a PA that could satisfy our request and ultimately tried to create a new PA that would overlap with the missed one. To makes sure we handle that case while still keeping the performance of the rbtree, we make use of the fact that the only pa that could possibly overlap the original goal start is the one that satisfies the below conditions: 1. It must have it's logical start immediately to the left of (ie less than) original logical start. 2. It must not be deleted To find this pa we use the following traversal method: 1. Descend into the rbtree normally to find the immediate neighboring PA. Here we keep descending irrespective of if the PA is deleted or if it overlaps with our request etc. The goal is to find an immediately adjacent PA. 2. If the found PA is on right of original goal, use rb_prev() to find the left adjacent PA. 3. Check if this PA is deleted and keep moving left with rb_prev() until a non deleted PA is found. 4. This is the PA we are looking for. Now we can check if it can satisfy the original request and proceed accordingly. This approach also takes care of having deleted PAs in the tree. (While we are at it, also fix a possible overflow bug in calculating the end of a PA) [1] https://lore.kernel.org/linux-ext4/CA+G9fYv2FRpLqBZf34ZinR8bU2_ZRAUOjKAD3+tKRFaEQHtt8Q@mail.gmail.com/
Source: NVD (National Vulnerability Database)
CVSS Information
N/A
Source: NVD (National Vulnerability Database)
Vulnerability Type
N/A
Source: NVD (National Vulnerability Database)
Vulnerability Title
Linux kernel 安全漏洞
Source: CNNVD (China National Vulnerability Database)
Vulnerability Description
Linux kernel是美国Linux基金会的开源操作系统Linux所使用的内核。 Linux kernel存在安全漏洞，该漏洞源于ext4_mb_use_preallocated未正确处理rbtree遍历，可能导致预分配空间重叠。
Source: CNNVD (China National Vulnerability Database)
CVSS Information
N/A
Source: CNNVD (China National Vulnerability Database)
Vulnerability Type
N/A
Source: CNNVD (China National Vulnerability Database)

Affected Products

VendorProductAffected VersionsCPESubscribe
LinuxLinux 3872778664e36528caf8b27f355e75482f6d562d ~ 339fee69a1daa71d6f97e47a867e2c32419a2406 -
LinuxLinux 6.4 -

II. Public POCs for CVE-2023-53813

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III. Intelligence Information for CVE-2023-53813

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Same Patch Batch · Linux · 2025-12-09 · 152 CVEs total

CVE-2023-53827Bluetooth: L2CAP: Fix use-after-free in l2cap_disconnect_{req,rsp}
CVE-2023-53846f2fs: fix to do sanity check on direct node in truncate_dnode()
CVE-2023-53845nilfs2: fix infinite loop in nilfs_mdt_get_block()
CVE-2023-53844drm/ttm: Don't leak a resource on swapout move error
CVE-2023-53843net: openvswitch: reject negative ifindex
CVE-2023-53842ASoC: codecs: wcd-mbhc-v2: fix resource leaks on component remove
CVE-2023-53841devlink: report devlink_port_type_warn source device
CVE-2023-53840usb: early: xhci-dbc: Fix a potential out-of-bound memory access
CVE-2023-53839dccp: fix data-race around dp->dccps_mss_cache
CVE-2023-53838f2fs: synchronize atomic write aborts
CVE-2023-53837drm/msm: fix NULL-deref on snapshot tear down
CVE-2023-53836bpf, sockmap: Fix skb refcnt race after locking changes
CVE-2023-53834iio: adc: ina2xx: avoid NULL pointer dereference on OF device match
CVE-2023-53833drm/i915: Fix NULL ptr deref by checking new_crtc_state
CVE-2023-53832md/raid10: fix null-ptr-deref in raid10_sync_request
CVE-2023-53831net: read sk->sk_family once in sk_mc_loop()
CVE-2023-53830platform/x86: think-lmi: Fix memory leak when showing current settings
CVE-2023-53829f2fs: flush inode if atomic file is aborted
CVE-2023-53828Bluetooth: hci_sync: Avoid use-after-free in dbg for hci_add_adv_monitor()
CVE-2022-50675arm64: mte: Avoid setting PG_mte_tagged if no tags cleared or restored

Showing top 20 of 152 CVEs. View all on vendor page → →

IV. Related Vulnerabilities

Same product: Linux
Same vendor: Linux

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