cbcvebase.
CVE-2024-26589
published 2024-02-22

CVE-2024-26589: In the Linux kernel, the following vulnerability has been resolved: bpf: Reject variable offset alu on PTR_TO_FLOW_KEYS For PTR_TO_FLOW_KEYS…

PriorityP338high7.8CVSS 3.1
AVLACLPRLUINSUCHIHAH
EPSS
0.24%
15.1th percentile
In the Linux kernel, the following vulnerability has been resolved: bpf: Reject variable offset alu on PTR_TO_FLOW_KEYS For PTR_TO_FLOW_KEYS, check_flow_keys_access() only uses fixed off for validation. However, variable offset ptr alu is not prohibited for this ptr kind. So the variable offset is not checked. The following prog is accepted: func#0 @0 0: R1=ctx() R10=fp0 0: (bf) r6 = r1 ; R1=ctx() R6_w=ctx() 1: (79) r7 = *(u64 *)(r6 +144) ; R6_w=ctx() R7_w=flow_keys() 2: (b7) r8 = 1024 ; R8_w=1024 3: (37) r8 /= 1 ; R8_w=scalar() 4: (57) r8 &= 1024 ; R8_w=scalar(smin=smin32=0, smax=umax=smax32=umax32=1024,var_off=(0x0; 0x400)) 5: (0f) r7 += r8 mark_precise: frame0: last_idx 5 first_idx 0 subseq_idx -1 mark_precise: frame0: regs=r8 stack= before 4: (57) r8 &= 1024 mark_precise: frame0: regs=r8 stack= before 3: (37) r8 /= 1 mark_precise: frame0: regs=r8 stack= before 2: (b7) r8 = 1024 6: R7_w=flow_keys(smin=smin32=0,smax=umax=smax32=umax32=1024,var_off =(0x0; 0x400)) R8_w=scalar(smin=smin32=0,smax=umax=smax32=umax32=1024, var_off=(0x0; 0x400)) 6: (79) r0 = *(u64 *)(r7 +0) ; R0_w=scalar() 7: (95) exit This prog loads flow_keys to r7, and adds the variable offset r8 to r7, and finally causes out-of-bounds access: BUG: unable to handle page fault for address: ffffc90014c80038 [...] Call Trace: bpf_dispatcher_nop_func include/linux/bpf.h:1231 [inline] __bpf_prog_run include/linux/filter.h:651 [inline] bpf_prog_run include/linux/filter.h:658 [inline] bpf_prog_run_pin_on_cpu include/linux/filter.h:675 [inline] bpf_flow_dissect+0x15f/0x350 net/core/flow_dissector.c:991 bpf_prog_test_run_flow_dissector+0x39d/0x620 net/bpf/test_run.c:1359 bpf_prog_test_run kernel/bpf/syscall.c:4107 [inline] __sys_bpf+0xf8f/0x4560 kernel/bpf/syscall.c:5475 __do_sys_bpf kernel/bpf/syscall.c:5561 [inline] __se_sys_bpf kernel/bpf/syscall.c:5559 [inline] __x64_sys_bpf+0x73/0xb0 kernel/bpf/syscall.c:5559 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0x3f/0x110 arch/x86/entry

Affected

16 ranges
VendorProductVersion rangeFixed in
debianlinux< linux 6.1.76-1 (bookworm)linux 6.1.76-1 (bookworm)
linuxlinux
linuxlinux>= d58e468b1112dcd1d5193c0a89ff9f98b5a3e8b9 < 29ffa63f21bcdcef3e36b03cccf9d0cd031f6ab029ffa63f21bcdcef3e36b03cccf9d0cd031f6ab0
linuxlinux>= d58e468b1112dcd1d5193c0a89ff9f98b5a3e8b9 < 4108b86e324da42f7ed425bd71632fd844300dc84108b86e324da42f7ed425bd71632fd844300dc8
linuxlinux>= d58e468b1112dcd1d5193c0a89ff9f98b5a3e8b9 < e8d3872b617c21100c5ee4f64e513997a68c2e3de8d3872b617c21100c5ee4f64e513997a68c2e3d
linuxlinux>= d58e468b1112dcd1d5193c0a89ff9f98b5a3e8b9 < 1b500d5d6cecf98dd6ca88bc9e7ae1783c83e6d31b500d5d6cecf98dd6ca88bc9e7ae1783c83e6d3
linuxlinux>= d58e468b1112dcd1d5193c0a89ff9f98b5a3e8b9 < 22c7fa171a02d310e3a3f6ed46a698ca8a0060ed22c7fa171a02d310e3a3f6ed46a698ca8a0060ed
linuxlinux_kernel>= 0 < 6.1.76-16.1.76-1
linuxlinux_kernel>= 0 < 6.6.15-16.6.15-1
linuxlinux_kernel>= 0 < 6.6.15-16.6.15-1
linuxlinux_kernel>= 0 < 5.4.0-177.1975.4.0-177.197
linuxlinux_kernel>= 0 < 5.15.0-102.1125.15.0-102.112
linuxlinux_kernel>= 4.20 < 5.15.1485.15.148
linuxlinux_kernel>= 5.16.0 < 6.1.756.1.75
linuxlinux_kernel>= 6.2.0 < 6.6.146.6.14
linuxlinux_kernel>= 6.7.0 < 6.7.26.7.2

CVSS provenance

nvdv3.17.8HIGHCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
osv8.1HIGH
vendor_debian7.8HIGH
vendor_redhat7.8HIGH
vendor_ubuntu7.8HIGH
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