net: bonding: fix use-after-free in bond_xmit_broadcast()
In the Linux kernel, the following vulnerability has been resolved: net: bonding: fix use-after-free in bond_xmit_broadcast() bond_xmit_broadcast() reuses the original skb for the last slave (determined by bond_is_last_slave()) and clones it for others. Concurrent slave enslave/release can mutate the slave list during RCU-protected iteration, changing which slave is "last" mid-loop. This causes the original skb to be double-consumed (double-freed). Replace the racy bond_is_last_slave() check with a simple index comparison (i + 1 == slaves_count) against the pre-snapshot slave count taken via READ_ONCE() before the loop. This preserves the zero-copy optimization for the last slave while making the "last" determination stable against concurrent list mutations. The UAF can trigger the following crash: ================================================================== BUG: KASAN: slab-use-after-free in skb_clone Read of size 8 at addr ffff888100ef8d40 by task exploit/147 CPU: 1 UID: 0 PID: 147 Comm: exploit Not tainted 7.0.0-rc3+ #4 PREEMPTLAZY Call Trace: dump_stack_lvl (lib/dump_stack.c:123) print_report (mm/kasan/report.c:379 mm/kasan/report.c:482) kasan_report (mm/kasan/report.c:597) skb_clone (include/linux/skbuff.h:1724 include/linux/skbuff.h:1792 include/linux/skbuff.h:3396 net/core/skbuff.c:2108) bond_xmit_broadcast (drivers/net/bonding/bond_main.c:5334) bond_start_xmit (drivers/net/bonding/bond_main.c:5567 drivers/net/bonding/bond_main.c:5593) dev_hard_start_xmit (includ
CVE-2026-31419
Primary source · Revision 1
Imported from structured advisory data. Source references identify upstream records or fields; verify affected versions and your deployed configuration.
Security context
Source reference: cve:CVE-2026-31419
Linux
Source reference: /containers/cna/affected/0/product
- Affected versions
- Not stated in this record
- Fixed versions
- Not stated in this record
- Prerequisites
- Not stated in this record
Linux
Source reference: /containers/cna/affected/1/product
- Affected versions
- Not stated in this record
- Fixed versions
- Not stated in this record
- Prerequisites
- Not stated in this record
Structured affected-version data
Original package identities and version rules from this source.
[
{
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"product": "Linux",
"versions": [
{
"status": "affected",
"version": "4e5bd03ae34652cd932ab4c91c71c511793df75c",
"lessThan": "00752893f96b344f258c9c6de18b33171ac4872c",
"versionType": "git"
},
{
"status": "affected",
"version": "4e5bd03ae34652cd932ab4c91c71c511793df75c",
"lessThan": "2de5c8eea0a9db99dae7c36f4b541b74b41d3a04",
"versionType": "git"
},
{
"status": "affected",
"version": "4e5bd03ae34652cd932ab4c91c71c511793df75c",
"lessThan": "a0f661918edc79d7a75e468128af8d41e2a1a83a",
"versionType": "git"
},
{
"status": "affected",
"version": "4e5bd03ae34652cd932ab4c91c71c511793df75c",
"lessThan": "d4cc7e4c80b1634c7b1497574a2fdb18df6c026c",
"versionType": "git"
},
{
"status": "affected",
"version": "4e5bd03ae34652cd932ab4c91c71c511793df75c",
"lessThan": "f5b94654a4a19891a8108d66ef166de6c028c6cd",
"versionType": "git"
},
{
"status": "affected",
"version": "4e5bd03ae34652cd932ab4c91c71c511793df75c",
"lessThan": "2884bf72fb8f03409e423397319205de48adca16",
"versionType": "git"
},
{
"status": "affected",
"version": "20949c3816463e97c6f8fe84c0280c7e5ae83a8d",
"versionType": "git"
},
{
"status": "affected",
"version": "f1d206181f19b00b275b258fea1418718a2f4173",
"versionType": "git"
},
{
"status": "affected",
"version": "c1f1691ef84fa6d38fa5e5148eca073145e97ffa",
"versionType": "git"
},
{
"status": "affected",
"version": "5.10.94",
"lessThan": "5.11",
"versionType": "semver"
},
{
"status": "affected",
"version": "5.15.17",
"lessThan": "5.16",
"versionType": "semver"
},
{
"status": "affected",
"version": "5.16.3",
"lessThan": "5.17",
"versionType": "semver"
}
],
"programFiles": [
"drivers/net/bonding/bond_main.c"
],
"defaultStatus": "unaffected"
},
{
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"product": "Linux",
"versions": [
{
"status": "affected",
"version": "5.17"
},
{
"status": "unaffected",
"version": "0",
"lessThan": "5.17",
"versionType": "semver"
},
{
"status": "unaffected",
"version": "6.1.184",
"versionType": "semver",
"lessThanOrEqual": "6.1.*"
},
{
"status": "unaffected",
"version": "6.6.143",
"versionType": "semver",
"lessThanOrEqual": "6.6.*"
},
{
"status": "unaffected",
"version": "6.12.95",
"versionType": "semver",
"lessThanOrEqual": "6.12.*"
},
{
"status": "unaffected",
"version": "6.18.22",
"versionType": "semver",
"lessThanOrEqual": "6.18.*"
},
{
"status": "unaffected",
"version": "6.19.12",
"versionType": "semver",
"lessThanOrEqual": "6.19.*"
},
{
"status": "unaffected",
"version": "7.0",
"versionType": "original_commit_for_fix",
"lessThanOrEqual": "*"
}
],
"programFiles": [
"drivers/net/bonding/bond_main.c"
],
"defaultStatus": "affected"
}
]- Related CVEs
- CVE-2026-31419
Source reference:
/cveMetadata/cveId
Publisher severity
high
Source reference: /containers/cna/metrics
- Event
- #39873 · Revision 1
- Added to Heist Feed
- Publisher date