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 E55B474040 for ; Mon, 12 May 2025 00:26:53 +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=1747009614; cv=none; b=Kltyox1vPsk323xF/mR3PmFByIEmKsSMpYE5fGyywesEpvODMHf05MCeTHKQuIgcZAiFEzW3CMqIaEjgcdgfMwiRIESdNx8MzpcRUubuLN5W+i7nUimOsprxurhh1i7QVy/tU86AL2yIchxBpeJzwWUkkG6GLHKaxMPsWwygtT4= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1747009614; c=relaxed/simple; bh=vhDkEAQJznyF3tY8dq/skjt7tYN1qDhgHg33sEpumyA=; h=Date:To:From:Subject:Message-Id; b=BGYVGQP5kqYxkH0doY/gL2zGHLpiZQ5CGiCPOJAXv0vPqMRFotjitxv5OrhK0/ktz2LNysyzf84s9ipSclcS3draz735FUGse6G2DuSO2Cvdcl9qnBN0pATbj6fMuqicQmslnrCFtYN77d6BojAvQb008O3WEOoOfnyKltofzH0= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux-foundation.org header.i=@linux-foundation.org header.b=nahaMb4F; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux-foundation.org header.i=@linux-foundation.org header.b="nahaMb4F" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 4D156C4CEE4; Mon, 12 May 2025 00:26:53 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linux-foundation.org; s=korg; t=1747009613; bh=vhDkEAQJznyF3tY8dq/skjt7tYN1qDhgHg33sEpumyA=; h=Date:To:From:Subject:From; b=nahaMb4FhKo4EfowpPVsEe7Xe0s4a1ueHsQi7ysCwZsccQh2wOaoHyvSMrMV6Dfa6 SaQxyv7oAcp5qBxMDdzUMHS0ja+ABvbvmUpTXhEwPDRzw6i7/uRRLB20vz42tsYdvA bcX21PeE0IgTY59INfQkcj8y7MCmhkYfPp2xLrMA= Date: Sun, 11 May 2025 17:26:52 -0700 To: mm-commits@vger.kernel.org,ziy@nvidia.com,vbabka@suse.cz,surenb@google.com,shakeel.butt@linux.dev,mhocko@suse.com,jackmanb@google.com,hannes@cmpxchg.org,00107082@163.com,akpm@linux-foundation.org From: Andrew Morton Subject: [merged mm-hotfixes-stable] mm-codetag-move-tag-retrieval-back-upfront-in-__free_pages.patch removed from -mm tree Message-Id: <20250512002653.4D156C4CEE4@smtp.kernel.org> Precedence: bulk X-Mailing-List: mm-commits@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: The quilt patch titled Subject: mm/codetag: move tag retrieval back upfront in __free_pages() has been removed from the -mm tree. Its filename was mm-codetag-move-tag-retrieval-back-upfront-in-__free_pages.patch This patch was dropped because it was merged into the mm-hotfixes-stable branch of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm ------------------------------------------------------ From: David Wang <00107082@163.com> Subject: mm/codetag: move tag retrieval back upfront in __free_pages() Date: Tue, 6 May 2025 03:30:34 +0800 Commit 51ff4d7486f0 ("mm: avoid extra mem_alloc_profiling_enabled() checks") introduces a possible use-after-free scenario, when page is non-compound, page[0] could be released by other thread right after put_page_testzero failed in current thread, pgalloc_tag_sub_pages afterwards would manipulate an invalid page for accounting remaining pages: [timeline] [thread1] [thread2] | alloc_page non-compound V | get_page, rf counter inc V | in ___free_pages | put_page_testzero fails V | put_page, page released V | in ___free_pages, | pgalloc_tag_sub_pages | manipulate an invalid page V Restore __free_pages() to its state before, retrieve alloc tag beforehand. Link: https://lkml.kernel.org/r/20250505193034.91682-1-00107082@163.com Fixes: 51ff4d7486f0 ("mm: avoid extra mem_alloc_profiling_enabled() checks") Signed-off-by: David Wang <00107082@163.com> Acked-by: Suren Baghdasaryan Reviewed-by: Vlastimil Babka Cc: Brendan Jackman Cc: Johannes Weiner Cc: Michal Hocko Cc: Shakeel Butt Cc: Vlastimil Babka Cc: Zi Yan Signed-off-by: Andrew Morton --- include/linux/pgalloc_tag.h | 8 ++++++++ mm/page_alloc.c | 15 ++++++--------- 2 files changed, 14 insertions(+), 9 deletions(-) --- a/include/linux/pgalloc_tag.h~mm-codetag-move-tag-retrieval-back-upfront-in-__free_pages +++ a/include/linux/pgalloc_tag.h @@ -188,6 +188,13 @@ static inline struct alloc_tag *__pgallo return tag; } +static inline struct alloc_tag *pgalloc_tag_get(struct page *page) +{ + if (mem_alloc_profiling_enabled()) + return __pgalloc_tag_get(page); + return NULL; +} + void pgalloc_tag_split(struct folio *folio, int old_order, int new_order); void pgalloc_tag_swap(struct folio *new, struct folio *old); @@ -199,6 +206,7 @@ static inline void clear_page_tag_ref(st static inline void alloc_tag_sec_init(void) {} static inline void pgalloc_tag_split(struct folio *folio, int old_order, int new_order) {} static inline void pgalloc_tag_swap(struct folio *new, struct folio *old) {} +static inline struct alloc_tag *pgalloc_tag_get(struct page *page) { return NULL; } #endif /* CONFIG_MEM_ALLOC_PROFILING */ --- a/mm/page_alloc.c~mm-codetag-move-tag-retrieval-back-upfront-in-__free_pages +++ a/mm/page_alloc.c @@ -1151,14 +1151,9 @@ static inline void pgalloc_tag_sub(struc __pgalloc_tag_sub(page, nr); } -static inline void pgalloc_tag_sub_pages(struct page *page, unsigned int nr) +/* When tag is not NULL, assuming mem_alloc_profiling_enabled */ +static inline void pgalloc_tag_sub_pages(struct alloc_tag *tag, unsigned int nr) { - struct alloc_tag *tag; - - if (!mem_alloc_profiling_enabled()) - return; - - tag = __pgalloc_tag_get(page); if (tag) this_cpu_sub(tag->counters->bytes, PAGE_SIZE * nr); } @@ -1168,7 +1163,7 @@ static inline void pgalloc_tag_sub_pages static inline void pgalloc_tag_add(struct page *page, struct task_struct *task, unsigned int nr) {} static inline void pgalloc_tag_sub(struct page *page, unsigned int nr) {} -static inline void pgalloc_tag_sub_pages(struct page *page, unsigned int nr) {} +static inline void pgalloc_tag_sub_pages(struct alloc_tag *tag, unsigned int nr) {} #endif /* CONFIG_MEM_ALLOC_PROFILING */ @@ -5065,11 +5060,13 @@ static void ___free_pages(struct page *p { /* get PageHead before we drop reference */ int head = PageHead(page); + /* get alloc tag in case the page is released by others */ + struct alloc_tag *tag = pgalloc_tag_get(page); if (put_page_testzero(page)) __free_frozen_pages(page, order, fpi_flags); else if (!head) { - pgalloc_tag_sub_pages(page, (1 << order) - 1); + pgalloc_tag_sub_pages(tag, (1 << order) - 1); while (order-- > 0) __free_frozen_pages(page + (1 << order), order, fpi_flags); _ Patches currently in -mm which might be from 00107082@163.com are