cbcvebase.
CVE-2024-56631
published 2024-12-27

CVE-2024-56631: In the Linux kernel, the following vulnerability has been resolved: scsi: sg: Fix slab-use-after-free read in sg_release() Fix a use-after-free bug in…

PriorityP338high7.8CVSS 3.1
AVLACLPRLUINSUCHIHAH
EPSS
0.29%
20.8th percentile
In the Linux kernel, the following vulnerability has been resolved: scsi: sg: Fix slab-use-after-free read in sg_release() Fix a use-after-free bug in sg_release(), detected by syzbot with KASAN: BUG: KASAN: slab-use-after-free in lock_release+0x151/0xa30 kernel/locking/lockdep.c:5838 __mutex_unlock_slowpath+0xe2/0x750 kernel/locking/mutex.c:912 sg_release+0x1f4/0x2e0 drivers/scsi/sg.c:407 In sg_release(), the function kref_put(&sfp->f_ref, sg_remove_sfp) is called before releasing the open_rel_lock mutex. The kref_put() call may decrement the reference count of sfp to zero, triggering its cleanup through sg_remove_sfp(). This cleanup includes scheduling deferred work via sg_remove_sfp_usercontext(), which ultimately frees sfp. After kref_put(), sg_release() continues to unlock open_rel_lock and may reference sfp or sdp. If sfp has already been freed, this results in a slab-use-after-free error. Move the kref_put(&sfp->f_ref, sg_remove_sfp) call after unlocking the open_rel_lock mutex. This ensures: - No references to sfp or sdp occur after the reference count is decremented. - Cleanup functions such as sg_remove_sfp() and sg_remove_sfp_usercontext() can safely execute without impacting the mutex handling in sg_release(). The fix has been tested and validated by syzbot. This patch closes the bug reported at the following syzkaller link and ensures proper sequencing of resource cleanup and mutex operations, eliminating the risk of use-after-free errors in sg_release().

Affected

28 ranges· showing 25
VendorProductVersion rangeFixed in
debianlinux< linux 6.1.128-1 (bookworm)linux 6.1.128-1 (bookworm)
debianlinux-6.1< linux 6.1.128-1 (bookworm)linux 6.1.128-1 (bookworm)
linuxlinux
linuxlinux
linuxlinux>= 3.16.85 < 3.173.17
linuxlinux>= cc833acbee9db5ca8c6162b015b4c93863c6f821 < e19acb1926c4a1f30ee1ec84d8afba2d975bd534e19acb1926c4a1f30ee1ec84d8afba2d975bd534
linuxlinux>= cc833acbee9db5ca8c6162b015b4c93863c6f821 < 285ce1f89f8d414e7eecab5ef5118cd512596318285ce1f89f8d414e7eecab5ef5118cd512596318
linuxlinux>= cc833acbee9db5ca8c6162b015b4c93863c6f821 < 198b89dd5a595ee3f96e5ce5c448b0484cd0e53c198b89dd5a595ee3f96e5ce5c448b0484cd0e53c
linuxlinux>= cc833acbee9db5ca8c6162b015b4c93863c6f821 < 275b8347e21ab8193e93223a8394a806e4ba8918275b8347e21ab8193e93223a8394a806e4ba8918
linuxlinux>= cc833acbee9db5ca8c6162b015b4c93863c6f821 < 59b30afa578637169e2819536bb66459fdddc39d59b30afa578637169e2819536bb66459fdddc39d
linuxlinux>= cc833acbee9db5ca8c6162b015b4c93863c6f821 < 1f5e2f1ca5875728fcf62bc1a054707444ab49601f5e2f1ca5875728fcf62bc1a054707444ab4960
linuxlinux>= cc833acbee9db5ca8c6162b015b4c93863c6f821 < f10593ad9bc36921f623361c9e3dd96bd52d85eef10593ad9bc36921f623361c9e3dd96bd52d85ee
linuxlinux_kernel
linuxlinux_kernel>= 0 < 5.10.234-15.10.234-1
linuxlinux_kernel>= 0 < 6.1.128-16.1.128-1
linuxlinux_kernel>= 0 < 6.12.5-16.12.5-1
linuxlinux_kernel>= 0 < 6.12.5-16.12.5-1
linuxlinux_kernel>= 0 < 5.4.0-211.2315.4.0-211.231
linuxlinux_kernel>= 0 < 5.15.0-135.1465.15.0-135.146
linuxlinux_kernel>= 0 < 6.8.0-58.606.8.0-58.60
linuxlinux_kernel>= 0 < 4.4.0-268.3024.4.0-268.302
linuxlinux_kernel>= 0 < 4.15.0-237.2494.15.0-237.249
linuxlinux_kernel>= 3.16.85 < 6.6.666.6.66
linuxlinux_kernel>= 6.7 < 6.12.56.12.5
msrcazl3_kernel_6.6.64.2-9_on_azure_linux_3.0

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
Stop checking back — get the weekly exploitation signal.

Every Monday: what got weaponized or added to CISA KEV in the last seven days — each CVE cross-linked to its PoC, Nuclei template, and detection rule. Free, one email a week, unsubscribe in one click.