Re: [PATCH v2 stable 5.15 1/2] tcp: fix races in tcp_abort()

[Sasha Levin <sashal@kernel.org>]

[ Sasha's backport helper bot ]

Hi,

✅ All tests passed successfully. No issues detected.
No action required from the submitter.

The upstream commit SHA1 provided is correct: 5ce4645c23cf5f048eb8e9ce49e514bababdee85

WARNING: Author mismatch between patch and upstream commit:
Backport author: Youngmin Nam<youngmin.nam@samsung.com>
Commit author: Eric Dumazet<edumazet@google.com>

Status in newer kernel trees:
6.13.y | Present (exact SHA1)
6.12.y | Present (exact SHA1)
6.6.y | Present (different SHA1: aa5229129a55)
6.1.y | Present (different SHA1: a1146efaea31)

Note: The patch differs from the upstream commit:
---
1:  5ce4645c23cf5 ! 1:  2295e520401c3 tcp: fix races in tcp_abort()
    @@ Commit message
         tcp_abort() has the same issue than the one fixed in the prior patch
         in tcp_write_err().
     
    +    commit 5ce4645c23cf5f048eb8e9ce49e514bababdee85 upstream.
    +
    +    To apply commit bac76cf89816bff06c4ec2f3df97dc34e150a1c4,
    +    this patch must be applied first.
    +
         In order to get consistent results from tcp_poll(), we must call
         sk_error_report() after tcp_done().
     
    @@ Commit message
         Acked-by: Neal Cardwell <ncardwell@google.com>
         Link: https://lore.kernel.org/r/20240528125253.1966136-4-edumazet@google.com
         Signed-off-by: Jakub Kicinski <kuba@kernel.org>
    +    Cc: <stable@vger.kernel.org>
    +    [youngmin: Resolved minor conflict in net/ipv4/tcp.c]
    +    Signed-off-by: Youngmin Nam <youngmin.nam@samsung.com>
     
      ## net/ipv4/tcp.c ##
     @@ net/ipv4/tcp.c: int tcp_abort(struct sock *sk, int err)
    @@ net/ipv4/tcp.c: int tcp_abort(struct sock *sk, int err)
     -		smp_wmb();
     -		sk_error_report(sk);
      		if (tcp_need_reset(sk->sk_state))
    - 			tcp_send_active_reset(sk, GFP_ATOMIC,
    - 					      SK_RST_REASON_NOT_SPECIFIED);
    + 			tcp_send_active_reset(sk, GFP_ATOMIC);
     -		tcp_done(sk);
     +		tcp_done_with_error(sk, err);
      	}
---

Results of testing on various branches:

| Branch                    | Patch Apply | Build Test |
|---------------------------|-------------|------------|
| stable/linux-5.15.y       |  Success    |  Success   |