cbcvebase.
CVE-2024-40910
published 2024-07-12

CVE-2024-40910: In the Linux kernel, the following vulnerability has been resolved: ax25: Fix refcount imbalance on inbound connections When releasing a socket in…

PriorityP420medium5.5CVSS 3.1
AVLACLPRLUINSUCNINAH
EPSS
0.31%
23.1th percentile
In the Linux kernel, the following vulnerability has been resolved: ax25: Fix refcount imbalance on inbound connections When releasing a socket in ax25_release(), we call netdev_put() to decrease the refcount on the associated ax.25 device. However, the execution path for accepting an incoming connection never calls netdev_hold(). This imbalance leads to refcount errors, and ultimately to kernel crashes. A typical call trace for the above situation will start with one of the following errors: refcount_t: decrement hit 0; leaking memory. refcount_t: underflow; use-after-free. And will then have a trace like: Call Trace: ? show_regs+0x64/0x70 ? __warn+0x83/0x120 ? refcount_warn_saturate+0xb2/0x100 ? report_bug+0x158/0x190 ? prb_read_valid+0x20/0x30 ? handle_bug+0x3e/0x70 ? exc_invalid_op+0x1c/0x70 ? asm_exc_invalid_op+0x1f/0x30 ? refcount_warn_saturate+0xb2/0x100 ? refcount_warn_saturate+0xb2/0x100 ax25_release+0x2ad/0x360 __sock_release+0x35/0xa0 sock_close+0x19/0x20 [...] On reboot (or any attempt to remove the interface), the kernel gets stuck in an infinite loop: unregister_netdevice: waiting for ax0 to become free. Usage count = 0 This patch corrects these issues by ensuring that we call netdev_hold() and ax25_dev_hold() for new connections in ax25_accept(). This makes the logic leading to ax25_accept() match the logic for ax25_bind(): in both cases we increment the refcount, which is ultimately decremented in ax25_release().

Affected

32 ranges· showing 25
VendorProductVersion rangeFixed in
debianlinux< linux 6.1.99-1 (bookworm)linux 6.1.99-1 (bookworm)
debianlinux-6.1< linux 6.1.99-1 (bookworm)linux 6.1.99-1 (bookworm)
linuxlinux
linuxlinux
linuxlinux
linuxlinux
linuxlinux
linuxlinux
linuxlinux
linuxlinux>= 4.14.277 < 4.154.15
linuxlinux>= 4.19.240 < 4.204.20
linuxlinux>= 5.10.112 < 5.115.11
linuxlinux>= 5.15.35 < 5.165.16
linuxlinux>= 5.17.2 < 5.185.18
linuxlinux>= 5.4.190 < 5.55.5
linuxlinux>= 9fd75b66b8f68498454d685dc4ba13192ae069b0 < f4df9d6c8d4e4c818252b0419c2165d66eabd4ebf4df9d6c8d4e4c818252b0419c2165d66eabd4eb
linuxlinux>= 9fd75b66b8f68498454d685dc4ba13192ae069b0 < 52100fd74ad07b53a4666feafff1cd11436362d352100fd74ad07b53a4666feafff1cd11436362d3
linuxlinux>= 9fd75b66b8f68498454d685dc4ba13192ae069b0 < a723a6c8d4831cc8e2c7b0c9f3f0c010d4671964a723a6c8d4831cc8e2c7b0c9f3f0c010d4671964
linuxlinux>= 9fd75b66b8f68498454d685dc4ba13192ae069b0 < 3c34fb0bd4a4237592c5ecb5b2e2531900c557743c34fb0bd4a4237592c5ecb5b2e2531900c55774
linuxlinux_kernel
linuxlinux_kernel
linuxlinux_kernel>= 0 < 6.1.99-16.1.99-1
linuxlinux_kernel>= 0 < 6.9.7-16.9.7-1
linuxlinux_kernel>= 0 < 6.9.7-16.9.7-1
linuxlinux_kernel>= 0 < 5.4.0-204.2245.4.0-204.224

CVSS provenance

nvdv3.15.5MEDIUMCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
osv8.8HIGH
vendor_ubuntu8.8HIGH
vendor_debian5.5MEDIUM
vendor_redhat5.5MEDIUM
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