cbcvebase.
CVE-2021-47418
published 2024-05-21

CVE-2021-47418: In the Linux kernel, the following vulnerability has been resolved: net_sched: fix NULL deref in fifo_set_limit() syzbot reported another NULL deref in…

PriorityP421medium5.5CVSS 3.1
AVLACLPRLUINSUCNINAH
EPSS
0.23%
14.3th percentile
In the Linux kernel, the following vulnerability has been resolved: net_sched: fix NULL deref in fifo_set_limit() syzbot reported another NULL deref in fifo_set_limit() [1] I could repro the issue with : unshare -n tc qd add dev lo root handle 1:0 tbf limit 200000 burst 70000 rate 100Mbit tc qd replace dev lo parent 1:0 pfifo_fast tc qd change dev lo root handle 1:0 tbf limit 300000 burst 70000 rate 100Mbit pfifo_fast does not have a change() operation. Make fifo_set_limit() more robust about this. [1] BUG: kernel NULL pointer dereference, address: 0000000000000000 PGD 1cf99067 P4D 1cf99067 PUD 7ca49067 PMD 0 Oops: 0010 [#1] PREEMPT SMP KASAN CPU: 1 PID: 14443 Comm: syz-executor959 Not tainted 5.15.0-rc3-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:0x0 Code: Unable to access opcode bytes at RIP 0xffffffffffffffd6. RSP: 0018:ffffc9000e2f7310 EFLAGS: 00010246 RAX: dffffc0000000000 RBX: ffffffff8d6ecc00 RCX: 0000000000000000 RDX: 0000000000000000 RSI: ffff888024c27910 RDI: ffff888071e34000 RBP: ffff888071e34000 R08: 0000000000000001 R09: ffffffff8fcfb947 R10: 0000000000000001 R11: 0000000000000000 R12: ffff888024c27910 R13: ffff888071e34018 R14: 0000000000000000 R15: ffff88801ef74800 FS: 00007f321d897700(0000) GS:ffff8880b9d00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: ffffffffffffffd6 CR3: 00000000722c3000 CR4: 00000000003506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: fifo_set_limit net/sched/sch_fifo.c:242 [inline] fifo_set_limit+0x198/0x210 net/sched/sch_fifo.c:227 tbf_change+0x6ec/0x16d0 net/sched/sch_tbf.c:418 qdisc_change net/sched/sch_api.c:1332 [inline] tc_modify_qdisc+0xd9a/0x1a60 net/sched/sch_api.c:1634 rtnetlink_rcv_msg+0x413/0xb80 net/core/rtnetlink.c:5572 netlink_rcv_skb+0x153/0x420 net/netlink/af_netlink.c:2504 netlink_unicast_kernel net/

Affected

22 ranges
VendorProductVersion rangeFixed in
debianlinux< linux 5.14.12-1 (bookworm)linux 5.14.12-1 (bookworm)
linuxlinux
linuxlinux>= fb0305ce1b03f6ff17f84f2c63daccecb45f2805 < 0dd7ddc462b9c2d31eb5a9926a2cc63eaa3e9f520dd7ddc462b9c2d31eb5a9926a2cc63eaa3e9f52
linuxlinux>= fb0305ce1b03f6ff17f84f2c63daccecb45f2805 < 08d7056e8e250fd2e67dbea5be5fdecdd75bf6b408d7056e8e250fd2e67dbea5be5fdecdd75bf6b4
linuxlinux>= fb0305ce1b03f6ff17f84f2c63daccecb45f2805 < 26af64d71b6277841285fa40e3f7164a378dfda926af64d71b6277841285fa40e3f7164a378dfda9
linuxlinux>= fb0305ce1b03f6ff17f84f2c63daccecb45f2805 < d07098f45be868a9cdce6c616563c36c64dbbd87d07098f45be868a9cdce6c616563c36c64dbbd87
linuxlinux>= fb0305ce1b03f6ff17f84f2c63daccecb45f2805 < c951a3be5e8803e93bb49a0aca0d30457d3c1b67c951a3be5e8803e93bb49a0aca0d30457d3c1b67
linuxlinux>= fb0305ce1b03f6ff17f84f2c63daccecb45f2805 < acff2d182c0768a713cee77442caeb07668bd68facff2d182c0768a713cee77442caeb07668bd68f
linuxlinux>= fb0305ce1b03f6ff17f84f2c63daccecb45f2805 < fb58cd7991747b5e0b110c98c922d7b0e47a1f14fb58cd7991747b5e0b110c98c922d7b0e47a1f14
linuxlinux>= fb0305ce1b03f6ff17f84f2c63daccecb45f2805 < 560ee196fe9e5037e5015e2cdb14b3aecb1cd7dc560ee196fe9e5037e5015e2cdb14b3aecb1cd7dc
linuxlinux_kernel
linuxlinux_kernel>= 0 < 5.10.84-15.10.84-1
linuxlinux_kernel>= 0 < 5.14.12-15.14.12-1
linuxlinux_kernel>= 0 < 5.14.12-15.14.12-1
linuxlinux_kernel>= 0 < 5.14.12-15.14.12-1
linuxlinux_kernel>= 2.6.27 < 4.4.2894.4.289
linuxlinux_kernel>= 4.10 < 4.14.2514.14.251
linuxlinux_kernel>= 4.15 < 4.19.2114.19.211
linuxlinux_kernel>= 4.20 < 5.4.1535.4.153
linuxlinux_kernel>= 4.5 < 4.9.2874.9.287
linuxlinux_kernel>= 5.11 < 5.14.125.14.12
linuxlinux_kernel>= 5.5 < 5.10.735.10.73

CVSS provenance

nvdv3.15.5MEDIUMCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
osv5.5MEDIUM
vendor_debian5.5MEDIUM
vendor_redhat5.5MEDIUM
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