| From bippy-5f407fcff5a0 Mon Sep 17 00:00:00 2001 |
| From: Greg Kroah-Hartman <gregkh@linuxfoundation.org> |
| To: <linux-cve-announce@vger.kernel.org> |
| Reply-to: <cve@kernel.org>, <linux-kernel@vger.kernel.org> |
| Subject: CVE-2021-47249: net: rds: fix memory leak in rds_recvmsg |
| |
| 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 | } |
| |
| The Linux kernel CVE team has assigned CVE-2021-47249 to this issue. |
| |
| |
| Affected and fixed versions |
| =========================== |
| |
| Issue introduced in 2.6.30 with commit bdbe6fbc6a2f2ccfb384b141b257677d2a8d36fb and fixed in 4.4.274 with commit 8c3ec88b03e9e4ca117dcdc4204fd3edcd02084f |
| Issue introduced in 2.6.30 with commit bdbe6fbc6a2f2ccfb384b141b257677d2a8d36fb and fixed in 4.9.274 with commit 423c6939758fb3b9cf5abbd1e7792068a5c4ae8c |
| Issue introduced in 2.6.30 with commit bdbe6fbc6a2f2ccfb384b141b257677d2a8d36fb and fixed in 4.14.238 with commit 1f79bc8ae81c05eb112a53f981cb2c244ee50d02 |
| Issue introduced in 2.6.30 with commit bdbe6fbc6a2f2ccfb384b141b257677d2a8d36fb and fixed in 4.19.196 with commit 06b7cb0194bd1ede0dd27f3a946e7c0279fba44a |
| Issue introduced in 2.6.30 with commit bdbe6fbc6a2f2ccfb384b141b257677d2a8d36fb and fixed in 5.4.128 with commit 2038cd15eacdf7512755c27686822e0052eb9042 |
| Issue introduced in 2.6.30 with commit bdbe6fbc6a2f2ccfb384b141b257677d2a8d36fb and fixed in 5.10.46 with commit 5946fbf48355f5a8caeff72580c7658da5966b86 |
| Issue introduced in 2.6.30 with commit bdbe6fbc6a2f2ccfb384b141b257677d2a8d36fb and fixed in 5.12.13 with commit b25b60d076164edb3025e85aabd2cf50a5215b91 |
| Issue introduced in 2.6.30 with commit bdbe6fbc6a2f2ccfb384b141b257677d2a8d36fb and fixed in 5.13 with commit 49bfcbfd989a8f1f23e705759a6bb099de2cff9f |
| |
| Please see https://www.kernel.org for a full list of currently supported |
| kernel versions by the kernel community. |
| |
| Unaffected versions might change over time as fixes are backported to |
| older supported kernel versions. The official CVE entry at |
| https://cve.org/CVERecord/?id=CVE-2021-47249 |
| will be updated if fixes are backported, please check that for the most |
| up to date information about this issue. |
| |
| |
| Affected files |
| ============== |
| |
| The file(s) affected by this issue are: |
| net/rds/recv.c |
| |
| |
| Mitigation |
| ========== |
| |
| The Linux kernel CVE team recommends that you update to the latest |
| stable kernel version for this, and many other bugfixes. Individual |
| changes are never tested alone, but rather are part of a larger kernel |
| release. Cherry-picking individual commits is not recommended or |
| supported by the Linux kernel community at all. If however, updating to |
| the latest release is impossible, the individual changes to resolve this |
| issue can be found at these commits: |
| https://git.kernel.org/stable/c/8c3ec88b03e9e4ca117dcdc4204fd3edcd02084f |
| https://git.kernel.org/stable/c/423c6939758fb3b9cf5abbd1e7792068a5c4ae8c |
| https://git.kernel.org/stable/c/1f79bc8ae81c05eb112a53f981cb2c244ee50d02 |
| https://git.kernel.org/stable/c/06b7cb0194bd1ede0dd27f3a946e7c0279fba44a |
| https://git.kernel.org/stable/c/2038cd15eacdf7512755c27686822e0052eb9042 |
| https://git.kernel.org/stable/c/5946fbf48355f5a8caeff72580c7658da5966b86 |
| https://git.kernel.org/stable/c/b25b60d076164edb3025e85aabd2cf50a5215b91 |
| https://git.kernel.org/stable/c/49bfcbfd989a8f1f23e705759a6bb099de2cff9f |
