| Message ID | 20210506190617.2252059-1-arjunroy.kdev@gmail.com (mailing list archive) |
|---|---|
| State | Superseded |
| Delegated to: | Netdev Maintainers |
| Headers | show |
| Series | [net,v2] tcp: Specify cmsgbuf is user pointer for receive zerocopy. | 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 | fail | 1 blamed authors not CCed: kuba@kernel.org; 3 maintainers not CCed: yoshfuji@linux-ipv6.org dsahern@kernel.org kuba@kernel.org |
| 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 | success | total: 0 errors, 0 warnings, 0 checks, 7 lines checked |
| netdev/build_allmodconfig_warn | success | Errors and warnings before: 1 this patch: 1 |
| netdev/header_inline | success | Link |
On Thu, May 6, 2021 at 9:06 PM Arjun Roy <arjunroy.kdev@gmail.com> wrote: > > From: Arjun Roy <arjunroy@google.com> > > A prior change (1f466e1f15cf) introduces separate handling for > ->msg_control depending on whether the pointer is a kernel or user > pointer. However, while tcp receive zerocopy is using this field, it > is not properly annotating that the buffer in this case is a user > pointer. This can cause faults when the improper mechanism is used > within put_cmsg(). > > This patch simply annotates tcp receive zerocopy's use as explicitly > being a user pointer. > > Fixes: 7eeba1706eba ("tcp: Add receive timestamp support for receive zerocopy.") > Signed-off-by: Arjun Roy <arjunroy@google.com> Reviewed-by: Eric Dumazet <edumazet@google.com> > --- > > Changelog since v1: > - Updated "Fixes" tag and commit message to properly account for which > commit introduced buggy behaviour. > > net/ipv4/tcp.c | 1 + > 1 file changed, 1 insertion(+) > > diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c > index e14fd0c50c10..f1c1f9e3de72 100644 > --- a/net/ipv4/tcp.c > +++ b/net/ipv4/tcp.c > @@ -2039,6 +2039,7 @@ static void tcp_zc_finalize_rx_tstamp(struct sock *sk, > (__kernel_size_t)zc->msg_controllen; > cmsg_dummy.msg_flags = in_compat_syscall() > ? MSG_CMSG_COMPAT : 0; > + cmsg_dummy.msg_control_is_user = true; > zc->msg_flags = 0; > if (zc->msg_control == msg_control_addr && > zc->msg_controllen == cmsg_dummy.msg_controllen) { > -- > 2.31.1.607.g51e8a6a459-goog >
diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c index e14fd0c50c10..f1c1f9e3de72 100644 --- a/net/ipv4/tcp.c +++ b/net/ipv4/tcp.c @@ -2039,6 +2039,7 @@ static void tcp_zc_finalize_rx_tstamp(struct sock *sk, (__kernel_size_t)zc->msg_controllen; cmsg_dummy.msg_flags = in_compat_syscall() ? MSG_CMSG_COMPAT : 0; + cmsg_dummy.msg_control_is_user = true; zc->msg_flags = 0; if (zc->msg_control == msg_control_addr && zc->msg_controllen == cmsg_dummy.msg_controllen) {