From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id CCEF94963DA; Sat, 28 Feb 2026 17:46:01 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1772300761; cv=none; b=O/P1qlLfxMVmJQ9fOARG7eDnhWu3bIjNh5JUCOPcvAqz6G/2IYtKCcvogy7xvSrU4ljPLyj6xCTzWzhbb0ytcOAwNCpvuAfmnX3ioQRGpx/gvNoc2yG9PqmUzJ3lDH8ehFMHtkJQ5bVQ5SSdS3oFjei/BTLoNDhJ9hMZyYTILPY= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1772300761; c=relaxed/simple; bh=Lf6er7hIUYoGNxI8zjtR1nY1T9ukD1O6DpoqieGl/Z8=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=K98Y+cFil5SzTlJUbVd9Gi1cvMav2WWeWAWyN90z0CBPEgISp6kEv3qfiq94QcmWuYoLLzGujS7AqUOK5q+DybfhecnUKvh4mmyo3veaiA6hfyuuaonWdrytO92T0IS0fpKMDY7GZUkftdWTYUGQxWOLHloeQKINo/QonXpyDeE= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=TcpK7tLR; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="TcpK7tLR" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 4619FC19425; Sat, 28 Feb 2026 17:46:00 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1772300761; bh=Lf6er7hIUYoGNxI8zjtR1nY1T9ukD1O6DpoqieGl/Z8=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=TcpK7tLRzfZwIZNmMMYaRm8qwU73riS3wPP1Lvsbaj46DyEfVwOKUexkD6SoPNmF/ wUcjKZAJ3+nXz3uqgskOTojJxZlQowF9/x2AdjDk6bAqwL7ZxS00FQNrgroGZD3Hih UPXkcQCcTohIkXnJ/DsYJSmc4lS9QVXm7HyhRyGo3MhIwDbVTzn9xKnQJoir+fRuew l8Se+dYsiiw4Ttg0xRNMOiPj/AFfafJW3mgsxw/Bw+tJ4mTCsrhj/YYRTQ4OUROtmN wl+RpjtHW286a9XWgAGBxB0FMipQXFpWjqg0DDjpYUJBrCM0qmQ7oTsoRDpvfGKZmY F+UidbH1ti7ug== From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Andrii Nakryiko , Ruikai Peng , Thomas Gleixner , Shakeel Butt , syzbot+237b5b985b78c1da9600@syzkaller.appspotmail.com, Andrew Morton , Sasha Levin Subject: [PATCH 6.19 795/844] procfs: fix possible double mmput() in do_procmap_query() Date: Sat, 28 Feb 2026 12:31:48 -0500 Message-ID: <20260228173244.1509663-796-sashal@kernel.org> X-Mailer: git-send-email 2.51.0 In-Reply-To: <20260228173244.1509663-1-sashal@kernel.org> References: <20260228173244.1509663-1-sashal@kernel.org> Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit From: Andrii Nakryiko [ Upstream commit 61dc9f776705d6db6847c101b98fa4f0e9eb6fa3 ] When user provides incorrectly sized buffer for build ID for PROCMAP_QUERY we return with -ENAMETOOLONG error. After recent changes this condition happens later, after we unlocked mmap_lock/per-VMA lock and did mmput(), so original goto out is now wrong and will double-mmput() mm_struct. Fix by jumping further to clean up only vm_file and name_buf. Link: https://lkml.kernel.org/r/20260210192738.3041609-1-andrii@kernel.org Fixes: b5cbacd7f86f ("procfs: avoid fetching build ID while holding VMA lock") Signed-off-by: Andrii Nakryiko Reported-by: Ruikai Peng Reported-by: Thomas Gleixner Tested-by: Thomas Gleixner Reviewed-by: Shakeel Butt Reported-by: syzbot+237b5b985b78c1da9600@syzkaller.appspotmail.com Cc: Ruikai Peng Closes: https://lkml.kernel.org/r/CAFD3drOJANTZPuyiqMdqpiRwOKnHwv5QgMNZghCDr-WxdiHvMg@mail.gmail.com Closes: https://lore.kernel.org/all/698aaf3c.050a0220.3b3015.0088.GAE@google.com/T/#u Cc: Signed-off-by: Andrew Morton Signed-off-by: Sasha Levin --- fs/proc/task_mmu.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/fs/proc/task_mmu.c b/fs/proc/task_mmu.c index 26188a4ad1abd..2f55efc368162 100644 --- a/fs/proc/task_mmu.c +++ b/fs/proc/task_mmu.c @@ -780,7 +780,7 @@ static int do_procmap_query(struct mm_struct *mm, void __user *uarg) } else { if (karg.build_id_size < build_id_sz) { err = -ENAMETOOLONG; - goto out; + goto out_file; } karg.build_id_size = build_id_sz; } @@ -808,6 +808,7 @@ static int do_procmap_query(struct mm_struct *mm, void __user *uarg) out: query_vma_teardown(&lock_ctx); mmput(mm); +out_file: if (vm_file) fput(vm_file); kfree(name_buf); -- 2.51.0