| Message ID | 0871af1e816f5239aaf546fcbc24af31aeec780f.1626556759.git.lucien.xin@gmail.com (mailing list archive) |
|---|---|
| State | Accepted |
| Commit | 2f3fdd8d4805015fa964807e1c7f3d88f31bd389 |
| Delegated to: | Netdev Maintainers |
| Headers | show |
| Series | [net] sctp: trim optlen when it's a huge value in sctp_setsockopt | expand |
| Context | Check | Description |
|---|---|---|
| netdev/cover_letter | success | Link |
| netdev/fixes_present | success | Link |
| netdev/patch_count | success | Link |
| netdev/tree_selection | success | Clearly marked for net |
| netdev/subject_prefix | success | Link |
| netdev/cc_maintainers | warning | 2 maintainers not CCed: vyasevich@gmail.com nhorman@tuxdriver.com |
| netdev/source_inline | success | Was 0 now: 0 |
| netdev/verify_signedoff | success | Link |
| netdev/module_param | success | Was 0 now: 0 |
| netdev/build_32bit | success | Errors and warnings before: 1 this patch: 1 |
| netdev/kdoc | success | Errors and warnings before: 0 this patch: 0 |
| netdev/verify_fixes | success | Link |
| netdev/checkpatch | warning | WARNING: line length of 84 exceeds 80 columns WARNING: line length of 94 exceeds 80 columns |
| netdev/build_allmodconfig_warn | success | Errors and warnings before: 1 this patch: 1 |
| netdev/header_inline | success | Link |
Hello: This patch was applied to netdev/net.git (refs/heads/master): On Sat, 17 Jul 2021 17:19:19 -0400 you wrote: > After commit ca84bd058dae ("sctp: copy the optval from user space in > sctp_setsockopt"), it does memory allocation in sctp_setsockopt with > the optlen, and it would fail the allocation and return error if the > optlen from user space is a huge value. > > This breaks some sockopts, like SCTP_HMAC_IDENT, SCTP_RESET_STREAMS and > SCTP_AUTH_KEY, as when processing these sockopts before, optlen would > be trimmed to a biggest value it needs when optlen is a huge value, > instead of failing the allocation and returning error. > > [...] Here is the summary with links: - [net] sctp: trim optlen when it's a huge value in sctp_setsockopt https://git.kernel.org/netdev/net/c/2f3fdd8d4805 You are awesome, thank you! -- Deet-doot-dot, I am a bot. https://korg.docs.kernel.org/patchwork/pwbot.html
diff --git a/net/sctp/socket.c b/net/sctp/socket.c index e64e01f61b11..6b937bfd4751 100644 --- a/net/sctp/socket.c +++ b/net/sctp/socket.c @@ -4577,6 +4577,10 @@ static int sctp_setsockopt(struct sock *sk, int level, int optname, } if (optlen > 0) { + /* Trim it to the biggest size sctp sockopt may need if necessary */ + optlen = min_t(unsigned int, optlen, + PAGE_ALIGN(USHRT_MAX + + sizeof(__u16) * sizeof(struct sctp_reset_streams))); kopt = memdup_sockptr(optval, optlen); if (IS_ERR(kopt)) return PTR_ERR(kopt);
After commit ca84bd058dae ("sctp: copy the optval from user space in sctp_setsockopt"), it does memory allocation in sctp_setsockopt with the optlen, and it would fail the allocation and return error if the optlen from user space is a huge value. This breaks some sockopts, like SCTP_HMAC_IDENT, SCTP_RESET_STREAMS and SCTP_AUTH_KEY, as when processing these sockopts before, optlen would be trimmed to a biggest value it needs when optlen is a huge value, instead of failing the allocation and returning error. This patch is to fix the allocation failure when it's a huge optlen from user space by trimming it to the biggest size sctp sockopt may need when necessary, and this biggest size is from sctp_setsockopt_reset_streams() for SCTP_RESET_STREAMS, which is bigger than those for SCTP_HMAC_IDENT and SCTP_AUTH_KEY. Fixes: ca84bd058dae ("sctp: copy the optval from user space in sctp_setsockopt") Signed-off-by: Xin Long <lucien.xin@gmail.com> --- net/sctp/socket.c | 4 ++++ 1 file changed, 4 insertions(+)