cbcvebase.
CVE-2022-49840
published 2025-05-01

CVE-2022-49840: In the Linux kernel, the following vulnerability has been resolved: bpf, test_run: Fix alignment problem in bpf_prog_test_run_skb() We got a syzkaller problem…

PriorityP339high7.8CVSS 3.1
AVLACLPRLUINSUCHIHAH
EPSS
0.20%
9.8th percentile
In the Linux kernel, the following vulnerability has been resolved: bpf, test_run: Fix alignment problem in bpf_prog_test_run_skb() We got a syzkaller problem because of aarch64 alignment fault if KFENCE enabled. When the size from user bpf program is an odd number, like 399, 407, etc, it will cause the struct skb_shared_info's unaligned access. As seen below: BUG: KFENCE: use-after-free read in __skb_clone+0x23c/0x2a0 net/core/skbuff.c:1032 Use-after-free read at 0xffff6254fffac077 (in kfence-#213): __lse_atomic_add arch/arm64/include/asm/atomic_lse.h:26 [inline] arch_atomic_add arch/arm64/include/asm/atomic.h:28 [inline] arch_atomic_inc include/linux/atomic-arch-fallback.h:270 [inline] atomic_inc include/asm-generic/atomic-instrumented.h:241 [inline] __skb_clone+0x23c/0x2a0 net/core/skbuff.c:1032 skb_clone+0xf4/0x214 net/core/skbuff.c:1481 ____bpf_clone_redirect net/core/filter.c:2433 [inline] bpf_clone_redirect+0x78/0x1c0 net/core/filter.c:2420 bpf_prog_d3839dd9068ceb51+0x80/0x330 bpf_dispatcher_nop_func include/linux/bpf.h:728 [inline] bpf_test_run+0x3c0/0x6c0 net/bpf/test_run.c:53 bpf_prog_test_run_skb+0x638/0xa7c net/bpf/test_run.c:594 bpf_prog_test_run kernel/bpf/syscall.c:3148 [inline] __do_sys_bpf kernel/bpf/syscall.c:4441 [inline] __se_sys_bpf+0xad0/0x1634 kernel/bpf/syscall.c:4381 kfence-#213: 0xffff6254fffac000-0xffff6254fffac196, size=407, cache=kmalloc-512 allocated by task 15074 on cpu 0 at 1342.585390s: kmalloc include/linux/slab.h:568 [inline] kzalloc include/linux/slab.h:675 [inline] bpf_test_init.isra.0+0xac/0x290 net/bpf/test_run.c:191 bpf_prog_test_run_skb+0x11c/0xa7c net/bpf/test_run.c:512 bpf_prog_test_run kernel/bpf/syscall.c:3148 [inline] __do_sys_bpf kernel/bpf/syscall.c:4441 [inline] __se_sys_bpf+0xad0/0x1634 kernel/bpf/syscall.c:4381 __arm64_sys_bpf+0x50/0x60 kernel/bpf/syscall.c:4381 To fix the problem, we adjust @size so that (@size + @hearoom) is a multiple of SMP_CACHE_BYTES. So we make sure the struct skb_shared_info is aligne

Affected

20 ranges
VendorProductVersion rangeFixed in
debianlinux< linux 6.0.10-1 (bookworm)linux 6.0.10-1 (bookworm)
linuxlinux——
linuxlinux>= 1cf1cae963c2e6032aebe1637e995bc2f5d330f4 < 047824a730699c6c66df43306b80f700c9dfc2fd047824a730699c6c66df43306b80f700c9dfc2fd
linuxlinux>= 1cf1cae963c2e6032aebe1637e995bc2f5d330f4 < 730fb1ef974a13915bc7651364d8b3318891cd70730fb1ef974a13915bc7651364d8b3318891cd70
linuxlinux>= 1cf1cae963c2e6032aebe1637e995bc2f5d330f4 < 7a704dbfd3735304e261f2787c52fbc7c38847367a704dbfd3735304e261f2787c52fbc7c3884736
linuxlinux>= 1cf1cae963c2e6032aebe1637e995bc2f5d330f4 < e60f37a1d379c821c17b08f366412dce9ef3d99fe60f37a1d379c821c17b08f366412dce9ef3d99f
linuxlinux>= 1cf1cae963c2e6032aebe1637e995bc2f5d330f4 < eaa8edd86514afac9deb9bf9a5053e74f37edf40eaa8edd86514afac9deb9bf9a5053e74f37edf40
linuxlinux>= 1cf1cae963c2e6032aebe1637e995bc2f5d330f4 < 1b597f2d6a55e9f549989913860ad5170da049641b597f2d6a55e9f549989913860ad5170da04964
linuxlinux>= 1cf1cae963c2e6032aebe1637e995bc2f5d330f4 < d3fd203f36d46aa29600a72d57a1b61af80e4a25d3fd203f36d46aa29600a72d57a1b61af80e4a25
linuxlinux_kernel——
linuxlinux_kernel>= 0 < 5.10.158-15.10.158-1
linuxlinux_kernel>= 0 < 6.0.10-16.0.10-1
linuxlinux_kernel>= 0 < 6.0.10-16.0.10-1
linuxlinux_kernel>= 0 < 6.0.10-16.0.10-1
linuxlinux_kernel>= 4.12 < 4.14.3004.14.300
linuxlinux_kernel>= 4.15 < 4.19.2674.19.267
linuxlinux_kernel>= 4.20 < 5.4.2255.4.225
linuxlinux_kernel>= 5.11 < 5.15.805.15.80
linuxlinux_kernel>= 5.16 < 6.0.106.0.10
linuxlinux_kernel>= 5.5 < 5.10.1565.10.156

CVSS provenance

nvdv3.17.8HIGHCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
osv7.8HIGH
vendor_debian7.8HIGH
vendor_redhat7.8HIGH
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