cbcvebase.
CVE-2024-39463
published 2024-06-25

CVE-2024-39463: In the Linux kernel, the following vulnerability has been resolved: 9p: add missing locking around taking dentry fid list Fix a use-after-free on dentry's…

PriorityP339high7.8CVSS 3.1
AVLACLPRLUINSUCHIHAH
EPSS
0.25%
16.8th percentile
In the Linux kernel, the following vulnerability has been resolved: 9p: add missing locking around taking dentry fid list Fix a use-after-free on dentry's d_fsdata fid list when a thread looks up a fid through dentry while another thread unlinks it: UAF thread: refcount_t: addition on 0; use-after-free. p9_fid_get linux/./include/net/9p/client.h:262 v9fs_fid_find+0x236/0x280 linux/fs/9p/fid.c:129 v9fs_fid_lookup_with_uid linux/fs/9p/fid.c:181 v9fs_fid_lookup+0xbf/0xc20 linux/fs/9p/fid.c:314 v9fs_vfs_getattr_dotl+0xf9/0x360 linux/fs/9p/vfs_inode_dotl.c:400 vfs_statx+0xdd/0x4d0 linux/fs/stat.c:248 Freed by: p9_fid_destroy (inlined) p9_client_clunk+0xb0/0xe0 linux/net/9p/client.c:1456 p9_fid_put linux/./include/net/9p/client.h:278 v9fs_dentry_release+0xb5/0x140 linux/fs/9p/vfs_dentry.c:55 v9fs_remove+0x38f/0x620 linux/fs/9p/vfs_inode.c:518 vfs_unlink+0x29a/0x810 linux/fs/namei.c:4335 The problem is that d_fsdata was not accessed under d_lock, because d_release() normally is only called once the dentry is otherwise no longer accessible but since we also call it explicitly in v9fs_remove that lock is required: move the hlist out of the dentry under lock then unref its fids once they are no longer accessible.

Affected

19 ranges
VendorProductVersion rangeFixed in
debianlinux< linux 6.1.94-1 (bookworm)linux 6.1.94-1 (bookworm)
linuxlinux
linuxlinux>= 154372e67d4053e56591245eb413686621941333 < 3bb6763a8319170c2d41c4232c8e7e4c37dcacfb3bb6763a8319170c2d41c4232c8e7e4c37dcacfb
linuxlinux>= 154372e67d4053e56591245eb413686621941333 < cb299cdba09f46f090b843d78ba26b667d50a456cb299cdba09f46f090b843d78ba26b667d50a456
linuxlinux>= 154372e67d4053e56591245eb413686621941333 < f0c5c944c6d8614c19e6e9a97fd2011dcd30e8f5f0c5c944c6d8614c19e6e9a97fd2011dcd30e8f5
linuxlinux>= 154372e67d4053e56591245eb413686621941333 < fe17ebf22feb4ad7094d597526d558a49aac92b4fe17ebf22feb4ad7094d597526d558a49aac92b4
linuxlinux>= 154372e67d4053e56591245eb413686621941333 < c898afdc15645efb555acb6d85b484eb40a45409c898afdc15645efb555acb6d85b484eb40a45409
linuxlinux_kernel
linuxlinux_kernel>= 0 < 6.1.94-16.1.94-1
linuxlinux_kernel>= 0 < 6.9.7-16.9.7-1
linuxlinux_kernel>= 0 < 6.9.7-16.9.7-1
linuxlinux_kernel>= 0 < 5.15.0-127.1375.15.0-127.137
linuxlinux_kernel>= 0 < 6.8.0-44.446.8.0-44.44
linuxlinux_kernel>= 5.11 < 5.15.1685.15.168
linuxlinux_kernel>= 5.16 < 6.1.946.1.94
linuxlinux_kernel>= 6.2 < 6.6.346.6.34
linuxlinux_kernel>= 6.7 < 6.9.56.9.5
msrccbl2_kernel_5.15.176.3-1_on_cbl_mariner_2.0
msrccbl2_kernel_5.15.182.1-1_on_cbl_mariner_2.0

CVSS provenance

nvdv3.17.8HIGHCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
osv8.8HIGH
vendor_ubuntu8.8HIGH
vendor_debian7.8HIGH
vendor_msrc7.8HIGH
vendor_redhat7.8HIGH
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