CVE-2021-47249
net: rds: fix memory leak in rds_recvmsg
- Published
- Updated
- Reserved
- Assigned by
- Linux
Description
In the Linux kernel, the following vulnerability has been resolved: net: rds: fix memory leak in rds_recvmsg Syzbot reported memory leak in rds. The problem was in unputted refcount in case of error. int rds_recvmsg(struct socket *sock, struct msghdr *msg, size_t size, int msg_flags) { ... if (!rds_next_incoming(rs, &inc)) { ... } After this "if" inc refcount incremented and if (rds_cmsg_recv(inc, msg, rs)) { ret = -EFAULT; goto out; } ... out: return ret; } in case of rds_cmsg_recv() fail the refcount won't be decremented. And it's easy to see from ftrace log, that rds_inc_addref() don't have rds_inc_put() pair in rds_recvmsg() after rds_cmsg_recv() 1) | rds_recvmsg() { 1) 3.721 us | rds_inc_addref(); 1) 3.853 us | rds_message_inc_copy_to_user(); 1) + 10.395 us | rds_cmsg_recv(); 1) + 34.260 us | }
Timeline
ID reserved
By Linux
- 41 days later
· 41 days later
Published
- 24 months later
· 24 months later
Record updated
Changes after publication (a new score, a public exploit, EPSS crossing 1, 10 or 50 %, leaving KEV) are kept since November 2026; earlier ones are not known.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| NVDNVD · Analyzed | 3.1 | Medium5.5 | CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H |
- EPSS (exploitation in 30 days)
- 0.24% · top 85% of all CVEs (7 Nov 2026)
- CISA SSVC
- Exploitation: none · Automatable: no · Technical impact: partial
The list uses the assigner's score when there is one, then CISA's, then NVD's: Medium 5.5.
Weakness
Affected products
- affected bdbe6fbc6a2f2ccfb384b141b257677d2a8d36fb – < 8c3ec88b03e9e4ca117dcdc4204fd3edcd02084f
- affected bdbe6fbc6a2f2ccfb384b141b257677d2a8d36fb – < 423c6939758fb3b9cf5abbd1e7792068a5c4ae8c
- affected bdbe6fbc6a2f2ccfb384b141b257677d2a8d36fb – < 1f79bc8ae81c05eb112a53f981cb2c244ee50d02
- affected bdbe6fbc6a2f2ccfb384b141b257677d2a8d36fb – < 06b7cb0194bd1ede0dd27f3a946e7c0279fba44a
- affected bdbe6fbc6a2f2ccfb384b141b257677d2a8d36fb – < 2038cd15eacdf7512755c27686822e0052eb9042
- affected bdbe6fbc6a2f2ccfb384b141b257677d2a8d36fb – < 5946fbf48355f5a8caeff72580c7658da5966b86
- affected bdbe6fbc6a2f2ccfb384b141b257677d2a8d36fb – < b25b60d076164edb3025e85aabd2cf50a5215b91
- affected bdbe6fbc6a2f2ccfb384b141b257677d2a8d36fb – < 49bfcbfd989a8f1f23e705759a6bb099de2cff9f
- affected 2.6.30
- unaffected < 2.6.30
- unaffected 4.4.274 – ≤ 4.4.*
- unaffected 4.9.274 – ≤ 4.9.*
- unaffected 4.14.238 – ≤ 4.14.*
- unaffected 4.19.196 – ≤ 4.19.*
- unaffected 5.4.128 – ≤ 5.4.*
- unaffected 5.10.46 – ≤ 5.10.*
- unaffected 5.12.13 – ≤ 5.12.*
- unaffected 5.13 – ≤ *
References (8)
- https://git.kernel.org/stable/c/8c3ec88b03e9e4ca117dcdc4204fd3edcd02084f (opens in a new tab)x_transferred
- https://git.kernel.org/stable/c/423c6939758fb3b9cf5abbd1e7792068a5c4ae8c (opens in a new tab)x_transferred
- https://git.kernel.org/stable/c/1f79bc8ae81c05eb112a53f981cb2c244ee50d02 (opens in a new tab)x_transferred
- https://git.kernel.org/stable/c/06b7cb0194bd1ede0dd27f3a946e7c0279fba44a (opens in a new tab)x_transferred
- https://git.kernel.org/stable/c/2038cd15eacdf7512755c27686822e0052eb9042 (opens in a new tab)x_transferred
- https://git.kernel.org/stable/c/5946fbf48355f5a8caeff72580c7658da5966b86 (opens in a new tab)x_transferred
- https://git.kernel.org/stable/c/b25b60d076164edb3025e85aabd2cf50a5215b91 (opens in a new tab)x_transferred
- https://git.kernel.org/stable/c/49bfcbfd989a8f1f23e705759a6bb099de2cff9f (opens in a new tab)x_transferred
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisories (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
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[](https://trackcve.app/cve/CVE-2021-47249)Record last updated .