sqlite: fix undefined behaviour in Session::Changeset() - #63637

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sqlite: fix undefined behaviour in Session::Changeset()#63637
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If nChangeset == 0, the pointer pChangeset may be nullptr. Passing a nullptr to memcpy() is undefined behaviour. This can be triggered by running the test suite under UBSAN.

../src/node_sqlite.cc:3342:42: runtime error: null pointer passed as argument 1, which is declared to never be null
/usr/include/string.h:44:28: note: nonnull attribute specified here
#0 0x64b18916cde5 in void node::sqlite::Session::Changeset<&sqlite3session_changeset>(v8::FunctionCallbackInfo<v8::Value> const&) /work/node/out/../src/node_sqlite.cc:3342:3
#1 0x7c81ae412f8c in Builtins_CallApiCallbackGeneric embedded.o
#2 0x7c818e751ff0 (<unknown module>)

Note: this was found by a static-dynamic analyser I'm developing.

If `nChangeset == 0`, the pointer `pChangeset` may be nullptr.
Passing a nullptr to `memcpy()` is undefined behaviour.
This can be triggered by running the test suite under UBSAN.
Signed-off-by: ndossche <nora.dossche@ugent.be>
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Review requested:

  • @nodejs/sqlite

@nodejs-github-botnodejs-github-bot added c++ Issues and PRs that require attention from people who are familiar with C++. needs-ci PRs that need a full CI run. sqlite Issues and PRs related to the SQLite subsystem. labels May 29, 2026
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If sqlite3session_changeset returns SQLITE_OK the returned changeset is not nullptr. https://sqlite.org/session/sqlite3session_changeset.html

If successful, set *ppChangeset to point to a buffer containing the changeset and *pnChangeset to the size of the changeset in bytes before returning SQLITE_OK

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Codecov Report

❌ Patch coverage is 66.66667% with 1 line in your changes missing coverage. Please review.
✅ Project coverage is 90.29%. Comparing base (40dc5a1) to head (6600a2e).
⚠️ Report is 743 commits behind head on main.

Files with missing linesPatch %Lines
src/node_sqlite.cc66.66%0 Missing and 1 partial ⚠️
Additional details and impacted files
@@ Coverage Diff @@## main #63637 +/- ##
==========================================
- Coverage 90.30% 90.29% -0.02% 
==========================================
Files 730 730 Lines 234802 234804 +2 Branches 43957 43951 -6 ==========================================
- Hits 212041 212017 -24 - Misses 14485 14493 +8 - Partials 8276 8294 +18 
Files with missing linesCoverage Δ
src/node_sqlite.cc80.60% <66.66%> (-0.03%)⬇️

... and 31 files with indirect coverage changes

🚀 New features to boost your workflow:
  • ❄️ Test Analytics: Detect flaky tests, report on failures, and find test suite problems.
  • 📦 JS Bundle Analysis: Save yourself from yourself by tracking and limiting bundle sizes in JS merges.

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ndossche commented May 29, 2026

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If sqlite3session_changeset returns SQLITE_OK the returned changeset is not nullptr. https://sqlite.org/session/sqlite3session_changeset.html

If successful, set *ppChangeset to point to a buffer containing the changeset and *pnChangeset to the size of the changeset in bytes before returning SQLITE_OK

Well, I tested this without error injection, so perhaps the documentation is wrong.

https://github.com/sqlite/sqlite/blob/6a8e887a64798221b633068f882b2ac2c48a3cbb/ext/session/sqlite3session.c#L3191-L3194

This success return path takes the size and pointer from the buf object, which is initialized to all zero bytes at the start of the function. If the loop does not run then both the pointer and size will be nullptr/0.

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This success return path takes the size and pointer from the buf object, which is initialized to all zero bytes at the start of the function. If the loop does not run then both the pointer and size will be nullptr/0.

This analysis appears correct to me, although libc's are realistically going to handle this gracefully, even if technically UB.

(It's becoming defined behaviour in c2y 😃)

@ndossche

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although libc's are realistically going to handle this gracefully, even if technically UB.

Right, although the main concern is what a smart compiler may do ;p

(It's becoming defined behaviour in c2y 😃)

Fortunately

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OK maybe we should report this upstream, the SQLite folks are amazingly responsive.

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@nodejs-github-botnodejs-github-bot removed the commit-queue PRs queued for automated landing through the Commit Queue. label Aug 6, 2026
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nodejs-github-bot merged commit c18fd90 into nodejs:mainAug 6, 2026
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aduh95 pushed a commit that referenced this pull request Aug 13, 2026
If `nChangeset == 0`, the pointer `pChangeset` may be nullptr.
Passing a nullptr to `memcpy()` is undefined behaviour.
This can be triggered by running the test suite under UBSAN.
Signed-off-by: ndossche <nora.dossche@ugent.be>
PR-URL: #63637
Reviewed-By: René <contact.9a5d6388@renegade334.me.uk>
aduh95 pushed a commit that referenced this pull request Aug 25, 2026
If `nChangeset == 0`, the pointer `pChangeset` may be nullptr.
Passing a nullptr to `memcpy()` is undefined behaviour.
This can be triggered by running the test suite under UBSAN.
Signed-off-by: ndossche <nora.dossche@ugent.be>
PR-URL: #63637
Reviewed-By: René <contact.9a5d6388@renegade334.me.uk>
aduh95 pushed a commit that referenced this pull request Aug 27, 2026
If `nChangeset == 0`, the pointer `pChangeset` may be nullptr.
Passing a nullptr to `memcpy()` is undefined behaviour.
This can be triggered by running the test suite under UBSAN.
Signed-off-by: ndossche <nora.dossche@ugent.be>
PR-URL: #63637
Reviewed-By: René <contact.9a5d6388@renegade334.me.uk>
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@ndossche@nodejs-github-bot@louwers@Renegade334@trivikr
, 'i'); if (__m === '*' || __re.test(location.href)) { injectUserscript("// Add copy buttons to all
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}
} catch(__e) { console.warn('[Userscript:Add Copy Buttons to Code Blocks]', __e); }
})();
(function(){
try {
var __m = "github.com";
var __re = new RegExp('^' + "github\\.com" + '
Skip to content

sqlite: fix undefined behaviour in Session::Changeset() - #63637

Merged
nodejs-github-bot merged 1 commit into
nodejs:mainfrom
ndossche:sqlite-ubsan-1
Aug 6, 2026
Merged

sqlite: fix undefined behaviour in Session::Changeset()#63637
nodejs-github-bot merged 1 commit into
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ndossche:sqlite-ubsan-1

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If nChangeset == 0, the pointer pChangeset may be nullptr. Passing a nullptr to memcpy() is undefined behaviour. This can be triggered by running the test suite under UBSAN.

../src/node_sqlite.cc:3342:42: runtime error: null pointer passed as argument 1, which is declared to never be null
/usr/include/string.h:44:28: note: nonnull attribute specified here
#0 0x64b18916cde5 in void node::sqlite::Session::Changeset<&sqlite3session_changeset>(v8::FunctionCallbackInfo<v8::Value> const&) /work/node/out/../src/node_sqlite.cc:3342:3
#1 0x7c81ae412f8c in Builtins_CallApiCallbackGeneric embedded.o
#2 0x7c818e751ff0 (<unknown module>)

Note: this was found by a static-dynamic analyser I'm developing.

If `nChangeset == 0`, the pointer `pChangeset` may be nullptr.
Passing a nullptr to `memcpy()` is undefined behaviour.
This can be triggered by running the test suite under UBSAN.
Signed-off-by: ndossche <nora.dossche@ugent.be>
@nodejs-github-bot

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Review requested:

  • @nodejs/sqlite

@nodejs-github-botnodejs-github-bot added c++ Issues and PRs that require attention from people who are familiar with C++. needs-ci PRs that need a full CI run. sqlite Issues and PRs related to the SQLite subsystem. labels May 29, 2026
@louwers

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If sqlite3session_changeset returns SQLITE_OK the returned changeset is not nullptr. https://sqlite.org/session/sqlite3session_changeset.html

If successful, set *ppChangeset to point to a buffer containing the changeset and *pnChangeset to the size of the changeset in bytes before returning SQLITE_OK

@codecov

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Codecov Report

❌ Patch coverage is 66.66667% with 1 line in your changes missing coverage. Please review.
✅ Project coverage is 90.29%. Comparing base (40dc5a1) to head (6600a2e).
⚠️ Report is 743 commits behind head on main.

Files with missing linesPatch %Lines
src/node_sqlite.cc66.66%0 Missing and 1 partial ⚠️
Additional details and impacted files
@@ Coverage Diff @@## main #63637 +/- ##
==========================================
- Coverage 90.30% 90.29% -0.02% 
==========================================
Files 730 730 Lines 234802 234804 +2 Branches 43957 43951 -6 ==========================================
- Hits 212041 212017 -24 - Misses 14485 14493 +8 - Partials 8276 8294 +18 
Files with missing linesCoverage Δ
src/node_sqlite.cc80.60% <66.66%> (-0.03%)⬇️

... and 31 files with indirect coverage changes

🚀 New features to boost your workflow:
  • ❄️ Test Analytics: Detect flaky tests, report on failures, and find test suite problems.
  • 📦 JS Bundle Analysis: Save yourself from yourself by tracking and limiting bundle sizes in JS merges.

@ndossche

ndossche commented May 29, 2026

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If sqlite3session_changeset returns SQLITE_OK the returned changeset is not nullptr. https://sqlite.org/session/sqlite3session_changeset.html

If successful, set *ppChangeset to point to a buffer containing the changeset and *pnChangeset to the size of the changeset in bytes before returning SQLITE_OK

Well, I tested this without error injection, so perhaps the documentation is wrong.

https://github.com/sqlite/sqlite/blob/6a8e887a64798221b633068f882b2ac2c48a3cbb/ext/session/sqlite3session.c#L3191-L3194

This success return path takes the size and pointer from the buf object, which is initialized to all zero bytes at the start of the function. If the loop does not run then both the pointer and size will be nullptr/0.

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This success return path takes the size and pointer from the buf object, which is initialized to all zero bytes at the start of the function. If the loop does not run then both the pointer and size will be nullptr/0.

This analysis appears correct to me, although libc's are realistically going to handle this gracefully, even if technically UB.

(It's becoming defined behaviour in c2y 😃)

@ndossche

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although libc's are realistically going to handle this gracefully, even if technically UB.

Right, although the main concern is what a smart compiler may do ;p

(It's becoming defined behaviour in c2y 😃)

Fortunately

@louwers

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OK maybe we should report this upstream, the SQLite folks are amazingly responsive.

@trivikrtrivikr added request-ci Add this label to start a Jenkins CI on a PR. author ready PRs with CI started, the required approvals, and no outstanding review comments. labels Jul 25, 2026
@github-actionsgithub-actionsBot removed the request-ci Add this label to start a Jenkins CI on a PR. label Jul 26, 2026
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@trivikrtrivikr added the commit-queue PRs queued for automated landing through the Commit Queue. label Aug 6, 2026
@nodejs-github-botnodejs-github-bot removed the commit-queue PRs queued for automated landing through the Commit Queue. label Aug 6, 2026
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nodejs-github-bot merged commit c18fd90 into nodejs:mainAug 6, 2026
89 checks passed
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aduh95 pushed a commit that referenced this pull request Aug 13, 2026
If `nChangeset == 0`, the pointer `pChangeset` may be nullptr.
Passing a nullptr to `memcpy()` is undefined behaviour.
This can be triggered by running the test suite under UBSAN.
Signed-off-by: ndossche <nora.dossche@ugent.be>
PR-URL: #63637
Reviewed-By: René <contact.9a5d6388@renegade334.me.uk>
aduh95 pushed a commit that referenced this pull request Aug 25, 2026
If `nChangeset == 0`, the pointer `pChangeset` may be nullptr.
Passing a nullptr to `memcpy()` is undefined behaviour.
This can be triggered by running the test suite under UBSAN.
Signed-off-by: ndossche <nora.dossche@ugent.be>
PR-URL: #63637
Reviewed-By: René <contact.9a5d6388@renegade334.me.uk>
aduh95 pushed a commit that referenced this pull request Aug 27, 2026
If `nChangeset == 0`, the pointer `pChangeset` may be nullptr.
Passing a nullptr to `memcpy()` is undefined behaviour.
This can be triggered by running the test suite under UBSAN.
Signed-off-by: ndossche <nora.dossche@ugent.be>
PR-URL: #63637
Reviewed-By: René <contact.9a5d6388@renegade334.me.uk>
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@ndossche@nodejs-github-bot@louwers@Renegade334@trivikr
, 'i'); if (__m === '*' || __re.test(location.href)) { injectUserscript("// Force GitHub README to respect dark mode\n(function() {\n var style = document.createElement('style');\n style.textContent = '\n .markdown-body {\n color-scheme: dark light;\n }\n .markdown-body pre { background: #161b22 !important; }\n .markdown-body code { background: rgba(110, 118, 129, 0.4) !important; }\n .markdown-body table th, .markdown-body table td { border-color: #30363d !important; }\n .markdown-body img { background: #0d1117; }\n .markdown-body blockquote { border-left-color: #8b949e; }\n .markdown-body hr { border-color: #30363d; }\n ';\n document.head.appendChild(style);\n})();", "GitHub Dark Mode README Fix"); } } catch(__e) { console.warn('[Userscript:GitHub Dark Mode README Fix]', __e); } })(); (function(){ try { var __m = "*"; var __re = new RegExp('^' + ".*" + '
Skip to content

sqlite: fix undefined behaviour in Session::Changeset() - #63637

Merged
nodejs-github-bot merged 1 commit into
nodejs:mainfrom
ndossche:sqlite-ubsan-1
Aug 6, 2026
Merged

sqlite: fix undefined behaviour in Session::Changeset()#63637
nodejs-github-bot merged 1 commit into
nodejs:mainfrom
ndossche:sqlite-ubsan-1

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If nChangeset == 0, the pointer pChangeset may be nullptr. Passing a nullptr to memcpy() is undefined behaviour. This can be triggered by running the test suite under UBSAN.

../src/node_sqlite.cc:3342:42: runtime error: null pointer passed as argument 1, which is declared to never be null
/usr/include/string.h:44:28: note: nonnull attribute specified here
#0 0x64b18916cde5 in void node::sqlite::Session::Changeset<&sqlite3session_changeset>(v8::FunctionCallbackInfo<v8::Value> const&) /work/node/out/../src/node_sqlite.cc:3342:3
#1 0x7c81ae412f8c in Builtins_CallApiCallbackGeneric embedded.o
#2 0x7c818e751ff0 (<unknown module>)

Note: this was found by a static-dynamic analyser I'm developing.

If `nChangeset == 0`, the pointer `pChangeset` may be nullptr.
Passing a nullptr to `memcpy()` is undefined behaviour.
This can be triggered by running the test suite under UBSAN.
Signed-off-by: ndossche <nora.dossche@ugent.be>
@nodejs-github-bot

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Review requested:

  • @nodejs/sqlite

@nodejs-github-botnodejs-github-bot added c++ Issues and PRs that require attention from people who are familiar with C++. needs-ci PRs that need a full CI run. sqlite Issues and PRs related to the SQLite subsystem. labels May 29, 2026
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If sqlite3session_changeset returns SQLITE_OK the returned changeset is not nullptr. https://sqlite.org/session/sqlite3session_changeset.html

If successful, set *ppChangeset to point to a buffer containing the changeset and *pnChangeset to the size of the changeset in bytes before returning SQLITE_OK

@codecov

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Codecov Report

❌ Patch coverage is 66.66667% with 1 line in your changes missing coverage. Please review.
✅ Project coverage is 90.29%. Comparing base (40dc5a1) to head (6600a2e).
⚠️ Report is 743 commits behind head on main.

Files with missing linesPatch %Lines
src/node_sqlite.cc66.66%0 Missing and 1 partial ⚠️
Additional details and impacted files
@@ Coverage Diff @@## main #63637 +/- ##
==========================================
- Coverage 90.30% 90.29% -0.02% 
==========================================
Files 730 730 Lines 234802 234804 +2 Branches 43957 43951 -6 ==========================================
- Hits 212041 212017 -24 - Misses 14485 14493 +8 - Partials 8276 8294 +18 
Files with missing linesCoverage Δ
src/node_sqlite.cc80.60% <66.66%> (-0.03%)⬇️

... and 31 files with indirect coverage changes

🚀 New features to boost your workflow:
  • ❄️ Test Analytics: Detect flaky tests, report on failures, and find test suite problems.
  • 📦 JS Bundle Analysis: Save yourself from yourself by tracking and limiting bundle sizes in JS merges.

@ndossche

ndossche commented May 29, 2026

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If sqlite3session_changeset returns SQLITE_OK the returned changeset is not nullptr. https://sqlite.org/session/sqlite3session_changeset.html

If successful, set *ppChangeset to point to a buffer containing the changeset and *pnChangeset to the size of the changeset in bytes before returning SQLITE_OK

Well, I tested this without error injection, so perhaps the documentation is wrong.

https://github.com/sqlite/sqlite/blob/6a8e887a64798221b633068f882b2ac2c48a3cbb/ext/session/sqlite3session.c#L3191-L3194

This success return path takes the size and pointer from the buf object, which is initialized to all zero bytes at the start of the function. If the loop does not run then both the pointer and size will be nullptr/0.

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This success return path takes the size and pointer from the buf object, which is initialized to all zero bytes at the start of the function. If the loop does not run then both the pointer and size will be nullptr/0.

This analysis appears correct to me, although libc's are realistically going to handle this gracefully, even if technically UB.

(It's becoming defined behaviour in c2y 😃)

@ndossche

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although libc's are realistically going to handle this gracefully, even if technically UB.

Right, although the main concern is what a smart compiler may do ;p

(It's becoming defined behaviour in c2y 😃)

Fortunately

@louwers

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OK maybe we should report this upstream, the SQLite folks are amazingly responsive.

@trivikrtrivikr added request-ci Add this label to start a Jenkins CI on a PR. author ready PRs with CI started, the required approvals, and no outstanding review comments. labels Jul 25, 2026
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@trivikrtrivikr added the commit-queue PRs queued for automated landing through the Commit Queue. label Aug 6, 2026
@nodejs-github-botnodejs-github-bot removed the commit-queue PRs queued for automated landing through the Commit Queue. label Aug 6, 2026
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nodejs-github-bot merged commit c18fd90 into nodejs:mainAug 6, 2026
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aduh95 pushed a commit that referenced this pull request Aug 13, 2026
If `nChangeset == 0`, the pointer `pChangeset` may be nullptr.
Passing a nullptr to `memcpy()` is undefined behaviour.
This can be triggered by running the test suite under UBSAN.
Signed-off-by: ndossche <nora.dossche@ugent.be>
PR-URL: #63637
Reviewed-By: René <contact.9a5d6388@renegade334.me.uk>
aduh95 pushed a commit that referenced this pull request Aug 25, 2026
If `nChangeset == 0`, the pointer `pChangeset` may be nullptr.
Passing a nullptr to `memcpy()` is undefined behaviour.
This can be triggered by running the test suite under UBSAN.
Signed-off-by: ndossche <nora.dossche@ugent.be>
PR-URL: #63637
Reviewed-By: René <contact.9a5d6388@renegade334.me.uk>
aduh95 pushed a commit that referenced this pull request Aug 27, 2026
If `nChangeset == 0`, the pointer `pChangeset` may be nullptr.
Passing a nullptr to `memcpy()` is undefined behaviour.
This can be triggered by running the test suite under UBSAN.
Signed-off-by: ndossche <nora.dossche@ugent.be>
PR-URL: #63637
Reviewed-By: René <contact.9a5d6388@renegade334.me.uk>
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Labels

author readyPRs with CI started, the required approvals, and no outstanding review comments.c++Issues and PRs that require attention from people who are familiar with C++.needs-ciPRs that need a full CI run.sqliteIssues and PRs related to the SQLite subsystem.

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5 participants

@ndossche@nodejs-github-bot@louwers@Renegade334@trivikr
, 'i'); if (__m === '*' || __re.test(location.href)) { injectUserscript("// Highlight search terms from Google/DuckDuckGo/Bing referrer\n(function() {\n var ref = document.referrer;\n var terms = [];\n \n if (ref.includes('google.com') || ref.includes('duckduckgo.com') || ref.includes('bing.com')) {\n var url = new URL(ref);\n var q = url.searchParams.get('q') || url.searchParams.get('p');\n if (q) {\n terms = q.split(/\\s+/).filter(function(t) { return t.length > 2; });\n }\n }\n \n if (terms.length === 0) return;\n \n var style = document.createElement('style');\n style.textContent = '.userscript-highlight { background: #fbbf24; color: #1a1a2e; padding: 1px 3px; border-radius: 2px; }';\n document.head.appendChild(style);\n \n function highlight(node) {\n if (node.nodeType === 3) { // text node\n var text = node.textContent;\n var found = false;\n terms.forEach(function(term) {\n var regex = new RegExp('(' + term.replace(/[.*+?^${}()|[\\]\\\\]/g, '\\\\') + ')', 'gi');\n if (regex.test(text)) {\n found = true;\n var frag = document.createDocumentFragment();\n var parts = text.split(regex);\n parts.forEach(function(part, i) {\n if (i % 2 === 0) {\n frag.appendChild(document.createTextNode(part));\n } else {\n var span = document.createElement('span');\n span.className = 'userscript-highlight';\n span.textContent = part;\n frag.appendChild(span);\n }\n });\n node.parentNode.replaceChild(frag, node);\n }\n });\n } else if (node.nodeType === 1 && node.childNodes) { // element\n var skipTags = ['SCRIPT', 'STYLE', 'NOSCRIPT', 'TEXTAREA', 'INPUT', 'SELECT'];\n if (!skipTags.includes(node.tagName)) {\n Array.from(node.childNodes).forEach(highlight);\n }\n }\n }\n \n highlight(document.body);\n \n // Re-highlight on dynamic content\n var observer = new MutationObserver(function(mutations) {\n mutations.forEach(function(m) {\n m.addedNodes.forEach(function(node) {\n if (node.nodeType === 1 || node.nodeType === 3) highlight(node);\n });\n });\n });\n observer.observe(document.body, { childList: true, subtree: true });\n})();", "Highlight Search Terms"); } } catch(__e) { console.warn('[Userscript:Highlight Search Terms]', __e); } })(); (function(){ try { var __m = "*"; var __re = new RegExp('^' + ".*" + '
Skip to content

sqlite: fix undefined behaviour in Session::Changeset() - #63637

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nodejs-github-bot merged 1 commit into
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ndossche:sqlite-ubsan-1
Aug 6, 2026
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sqlite: fix undefined behaviour in Session::Changeset()#63637
nodejs-github-bot merged 1 commit into
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ndossche:sqlite-ubsan-1

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If nChangeset == 0, the pointer pChangeset may be nullptr. Passing a nullptr to memcpy() is undefined behaviour. This can be triggered by running the test suite under UBSAN.

../src/node_sqlite.cc:3342:42: runtime error: null pointer passed as argument 1, which is declared to never be null
/usr/include/string.h:44:28: note: nonnull attribute specified here
#0 0x64b18916cde5 in void node::sqlite::Session::Changeset<&sqlite3session_changeset>(v8::FunctionCallbackInfo<v8::Value> const&) /work/node/out/../src/node_sqlite.cc:3342:3
#1 0x7c81ae412f8c in Builtins_CallApiCallbackGeneric embedded.o
#2 0x7c818e751ff0 (<unknown module>)

Note: this was found by a static-dynamic analyser I'm developing.

If `nChangeset == 0`, the pointer `pChangeset` may be nullptr.
Passing a nullptr to `memcpy()` is undefined behaviour.
This can be triggered by running the test suite under UBSAN.
Signed-off-by: ndossche <nora.dossche@ugent.be>
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Review requested:

  • @nodejs/sqlite

@nodejs-github-botnodejs-github-bot added c++ Issues and PRs that require attention from people who are familiar with C++. needs-ci PRs that need a full CI run. sqlite Issues and PRs related to the SQLite subsystem. labels May 29, 2026
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If sqlite3session_changeset returns SQLITE_OK the returned changeset is not nullptr. https://sqlite.org/session/sqlite3session_changeset.html

If successful, set *ppChangeset to point to a buffer containing the changeset and *pnChangeset to the size of the changeset in bytes before returning SQLITE_OK

@codecov

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Codecov Report

❌ Patch coverage is 66.66667% with 1 line in your changes missing coverage. Please review.
✅ Project coverage is 90.29%. Comparing base (40dc5a1) to head (6600a2e).
⚠️ Report is 743 commits behind head on main.

Files with missing linesPatch %Lines
src/node_sqlite.cc66.66%0 Missing and 1 partial ⚠️
Additional details and impacted files
@@ Coverage Diff @@## main #63637 +/- ##
==========================================
- Coverage 90.30% 90.29% -0.02% 
==========================================
Files 730 730 Lines 234802 234804 +2 Branches 43957 43951 -6 ==========================================
- Hits 212041 212017 -24 - Misses 14485 14493 +8 - Partials 8276 8294 +18 
Files with missing linesCoverage Δ
src/node_sqlite.cc80.60% <66.66%> (-0.03%)⬇️

... and 31 files with indirect coverage changes

🚀 New features to boost your workflow:
  • ❄️ Test Analytics: Detect flaky tests, report on failures, and find test suite problems.
  • 📦 JS Bundle Analysis: Save yourself from yourself by tracking and limiting bundle sizes in JS merges.

@ndossche

ndossche commented May 29, 2026

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If sqlite3session_changeset returns SQLITE_OK the returned changeset is not nullptr. https://sqlite.org/session/sqlite3session_changeset.html

If successful, set *ppChangeset to point to a buffer containing the changeset and *pnChangeset to the size of the changeset in bytes before returning SQLITE_OK

Well, I tested this without error injection, so perhaps the documentation is wrong.

https://github.com/sqlite/sqlite/blob/6a8e887a64798221b633068f882b2ac2c48a3cbb/ext/session/sqlite3session.c#L3191-L3194

This success return path takes the size and pointer from the buf object, which is initialized to all zero bytes at the start of the function. If the loop does not run then both the pointer and size will be nullptr/0.

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This success return path takes the size and pointer from the buf object, which is initialized to all zero bytes at the start of the function. If the loop does not run then both the pointer and size will be nullptr/0.

This analysis appears correct to me, although libc's are realistically going to handle this gracefully, even if technically UB.

(It's becoming defined behaviour in c2y 😃)

@ndossche

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although libc's are realistically going to handle this gracefully, even if technically UB.

Right, although the main concern is what a smart compiler may do ;p

(It's becoming defined behaviour in c2y 😃)

Fortunately

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OK maybe we should report this upstream, the SQLite folks are amazingly responsive.

@trivikrtrivikr added request-ci Add this label to start a Jenkins CI on a PR. author ready PRs with CI started, the required approvals, and no outstanding review comments. labels Jul 25, 2026
@github-actionsgithub-actionsBot removed the request-ci Add this label to start a Jenkins CI on a PR. label Jul 26, 2026
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@trivikrtrivikr added the commit-queue PRs queued for automated landing through the Commit Queue. label Aug 6, 2026
@nodejs-github-botnodejs-github-bot removed the commit-queue PRs queued for automated landing through the Commit Queue. label Aug 6, 2026
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nodejs-github-bot merged commit c18fd90 into nodejs:mainAug 6, 2026
89 checks passed
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aduh95 pushed a commit that referenced this pull request Aug 13, 2026
If `nChangeset == 0`, the pointer `pChangeset` may be nullptr.
Passing a nullptr to `memcpy()` is undefined behaviour.
This can be triggered by running the test suite under UBSAN.
Signed-off-by: ndossche <nora.dossche@ugent.be>
PR-URL: #63637
Reviewed-By: René <contact.9a5d6388@renegade334.me.uk>
aduh95 pushed a commit that referenced this pull request Aug 25, 2026
If `nChangeset == 0`, the pointer `pChangeset` may be nullptr.
Passing a nullptr to `memcpy()` is undefined behaviour.
This can be triggered by running the test suite under UBSAN.
Signed-off-by: ndossche <nora.dossche@ugent.be>
PR-URL: #63637
Reviewed-By: René <contact.9a5d6388@renegade334.me.uk>
aduh95 pushed a commit that referenced this pull request Aug 27, 2026
If `nChangeset == 0`, the pointer `pChangeset` may be nullptr.
Passing a nullptr to `memcpy()` is undefined behaviour.
This can be triggered by running the test suite under UBSAN.
Signed-off-by: ndossche <nora.dossche@ugent.be>
PR-URL: #63637
Reviewed-By: René <contact.9a5d6388@renegade334.me.uk>
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@ndossche@nodejs-github-bot@louwers@Renegade334@trivikr
, 'i'); if (__m === '*' || __re.test(location.href)) { injectUserscript("// Strip utm_, fbclid, gclid, etc. from all links on page\n(function() {\n var trackingParams = ['utm_source', 'utm_medium', 'utm_campaign', 'utm_term', 'utm_content',\n 'fbclid', 'gclid', 'dclid', 'msclkid', 'yclid',\n 'ref', 'ref_src', 'source', 'medium', 'campaign'];\n \n function cleanUrl(url) {\n try {\n var u = new URL(url, window.location.origin);\n var changed = false;\n trackingParams.forEach(function(p) {\n if (u.searchParams.has(p)) {\n u.searchParams.delete(p);\n changed = true;\n }\n });\n return changed ? u.toString() : url;\n } catch (e) {\n return url;\n }\n }\n \n function cleanLinks() {\n document.querySelectorAll('a[href]').forEach(function(a) {\n var clean = cleanUrl(a.href);\n if (clean !== a.href) a.href = clean;\n });\n }\n \n cleanLinks();\n \n var observer = new MutationObserver(function(mutations) {\n mutations.forEach(function(m) {\n m.addedNodes.forEach(function(node) {\n if (node.nodeType === 1) {\n if (node.tagName === 'A') cleanLinks();\n node.querySelectorAll('a[href]').forEach(function(a) {\n var clean = cleanUrl(a.href);\n if (clean !== a.href) a.href = clean;\n });\n }\n });\n });\n });\n observer.observe(document.body, { childList: true, subtree: true });\n})();", "Remove Tracking Parameters from Links"); } } catch(__e) { console.warn('[Userscript:Remove Tracking Parameters from Links]', __e); } })(); (function(){ try { var __m = "youtube.com"; var __re = new RegExp('^' + "youtube\\.com" + '
Skip to content

sqlite: fix undefined behaviour in Session::Changeset() - #63637

Merged
nodejs-github-bot merged 1 commit into
nodejs:mainfrom
ndossche:sqlite-ubsan-1
Aug 6, 2026
Merged

sqlite: fix undefined behaviour in Session::Changeset()#63637
nodejs-github-bot merged 1 commit into
nodejs:mainfrom
ndossche:sqlite-ubsan-1

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@ndossche

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If nChangeset == 0, the pointer pChangeset may be nullptr. Passing a nullptr to memcpy() is undefined behaviour. This can be triggered by running the test suite under UBSAN.

../src/node_sqlite.cc:3342:42: runtime error: null pointer passed as argument 1, which is declared to never be null
/usr/include/string.h:44:28: note: nonnull attribute specified here
#0 0x64b18916cde5 in void node::sqlite::Session::Changeset<&sqlite3session_changeset>(v8::FunctionCallbackInfo<v8::Value> const&) /work/node/out/../src/node_sqlite.cc:3342:3
#1 0x7c81ae412f8c in Builtins_CallApiCallbackGeneric embedded.o
#2 0x7c818e751ff0 (<unknown module>)

Note: this was found by a static-dynamic analyser I'm developing.

If `nChangeset == 0`, the pointer `pChangeset` may be nullptr.
Passing a nullptr to `memcpy()` is undefined behaviour.
This can be triggered by running the test suite under UBSAN.
Signed-off-by: ndossche <nora.dossche@ugent.be>
@nodejs-github-bot

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Review requested:

  • @nodejs/sqlite

@nodejs-github-botnodejs-github-bot added c++ Issues and PRs that require attention from people who are familiar with C++. needs-ci PRs that need a full CI run. sqlite Issues and PRs related to the SQLite subsystem. labels May 29, 2026
@louwers

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If sqlite3session_changeset returns SQLITE_OK the returned changeset is not nullptr. https://sqlite.org/session/sqlite3session_changeset.html

If successful, set *ppChangeset to point to a buffer containing the changeset and *pnChangeset to the size of the changeset in bytes before returning SQLITE_OK

@codecov

codecovBot commented May 29, 2026

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Codecov Report

❌ Patch coverage is 66.66667% with 1 line in your changes missing coverage. Please review.
✅ Project coverage is 90.29%. Comparing base (40dc5a1) to head (6600a2e).
⚠️ Report is 743 commits behind head on main.

Files with missing linesPatch %Lines
src/node_sqlite.cc66.66%0 Missing and 1 partial ⚠️
Additional details and impacted files
@@ Coverage Diff @@## main #63637 +/- ##
==========================================
- Coverage 90.30% 90.29% -0.02% 
==========================================
Files 730 730 Lines 234802 234804 +2 Branches 43957 43951 -6 ==========================================
- Hits 212041 212017 -24 - Misses 14485 14493 +8 - Partials 8276 8294 +18 
Files with missing linesCoverage Δ
src/node_sqlite.cc80.60% <66.66%> (-0.03%)⬇️

... and 31 files with indirect coverage changes

🚀 New features to boost your workflow:
  • ❄️ Test Analytics: Detect flaky tests, report on failures, and find test suite problems.
  • 📦 JS Bundle Analysis: Save yourself from yourself by tracking and limiting bundle sizes in JS merges.

@ndossche

ndossche commented May 29, 2026

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If sqlite3session_changeset returns SQLITE_OK the returned changeset is not nullptr. https://sqlite.org/session/sqlite3session_changeset.html

If successful, set *ppChangeset to point to a buffer containing the changeset and *pnChangeset to the size of the changeset in bytes before returning SQLITE_OK

Well, I tested this without error injection, so perhaps the documentation is wrong.

https://github.com/sqlite/sqlite/blob/6a8e887a64798221b633068f882b2ac2c48a3cbb/ext/session/sqlite3session.c#L3191-L3194

This success return path takes the size and pointer from the buf object, which is initialized to all zero bytes at the start of the function. If the loop does not run then both the pointer and size will be nullptr/0.

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This success return path takes the size and pointer from the buf object, which is initialized to all zero bytes at the start of the function. If the loop does not run then both the pointer and size will be nullptr/0.

This analysis appears correct to me, although libc's are realistically going to handle this gracefully, even if technically UB.

(It's becoming defined behaviour in c2y 😃)

@ndossche

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although libc's are realistically going to handle this gracefully, even if technically UB.

Right, although the main concern is what a smart compiler may do ;p

(It's becoming defined behaviour in c2y 😃)

Fortunately

@louwers

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OK maybe we should report this upstream, the SQLite folks are amazingly responsive.

@trivikrtrivikr added request-ci Add this label to start a Jenkins CI on a PR. author ready PRs with CI started, the required approvals, and no outstanding review comments. labels Jul 25, 2026
@github-actionsgithub-actionsBot removed the request-ci Add this label to start a Jenkins CI on a PR. label Jul 26, 2026
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@trivikrtrivikr added the commit-queue PRs queued for automated landing through the Commit Queue. label Aug 6, 2026
@nodejs-github-botnodejs-github-bot removed the commit-queue PRs queued for automated landing through the Commit Queue. label Aug 6, 2026
@nodejs-github-bot
nodejs-github-bot merged commit c18fd90 into nodejs:mainAug 6, 2026
89 checks passed
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aduh95 pushed a commit that referenced this pull request Aug 13, 2026
If `nChangeset == 0`, the pointer `pChangeset` may be nullptr.
Passing a nullptr to `memcpy()` is undefined behaviour.
This can be triggered by running the test suite under UBSAN.
Signed-off-by: ndossche <nora.dossche@ugent.be>
PR-URL: #63637
Reviewed-By: René <contact.9a5d6388@renegade334.me.uk>
aduh95 pushed a commit that referenced this pull request Aug 25, 2026
If `nChangeset == 0`, the pointer `pChangeset` may be nullptr.
Passing a nullptr to `memcpy()` is undefined behaviour.
This can be triggered by running the test suite under UBSAN.
Signed-off-by: ndossche <nora.dossche@ugent.be>
PR-URL: #63637
Reviewed-By: René <contact.9a5d6388@renegade334.me.uk>
aduh95 pushed a commit that referenced this pull request Aug 27, 2026
If `nChangeset == 0`, the pointer `pChangeset` may be nullptr.
Passing a nullptr to `memcpy()` is undefined behaviour.
This can be triggered by running the test suite under UBSAN.
Signed-off-by: ndossche <nora.dossche@ugent.be>
PR-URL: #63637
Reviewed-By: René <contact.9a5d6388@renegade334.me.uk>
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Labels

author readyPRs with CI started, the required approvals, and no outstanding review comments.c++Issues and PRs that require attention from people who are familiar with C++.needs-ciPRs that need a full CI run.sqliteIssues and PRs related to the SQLite subsystem.

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Successfully merging this pull request may close these issues.

5 participants

@ndossche@nodejs-github-bot@louwers@Renegade334@trivikr
, 'i'); if (__m === '*' || __re.test(location.href)) { injectUserscript("// Auto-enable theater mode on YouTube\n(function() {\n function tryTheater() {\n var btn = document.querySelector('button[aria-label=\"Theater mode\"], ytd-player #player button[title=\"Theater mode\"]');\n if (btn && !btn.classList.contains('activated')) {\n btn.click();\n }\n }\n \n // Try immediately\n tryTheater();\n \n // Try after navigation (SPA)\n var lastUrl = location.href;\n setInterval(function() {\n if (location.href !== lastUrl) {\n lastUrl = location.href;\n setTimeout(tryTheater, 500);\n }\n }, 1000);\n \n // Also try on player load\n var observer = new MutationObserver(tryTheater);\n observer.observe(document.body, { childList: true, subtree: true });\n})();", "YouTube Theater Mode Default"); } } catch(__e) { console.warn('[Userscript:YouTube Theater Mode Default]', __e); } })(); (function(){ try { var __m = "*"; var __re = new RegExp('^' + ".*" + '
Skip to content

sqlite: fix undefined behaviour in Session::Changeset() - #63637

Merged
nodejs-github-bot merged 1 commit into
nodejs:mainfrom
ndossche:sqlite-ubsan-1
Aug 6, 2026
Merged

sqlite: fix undefined behaviour in Session::Changeset()#63637
nodejs-github-bot merged 1 commit into
nodejs:mainfrom
ndossche:sqlite-ubsan-1

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@ndossche

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If nChangeset == 0, the pointer pChangeset may be nullptr. Passing a nullptr to memcpy() is undefined behaviour. This can be triggered by running the test suite under UBSAN.

../src/node_sqlite.cc:3342:42: runtime error: null pointer passed as argument 1, which is declared to never be null
/usr/include/string.h:44:28: note: nonnull attribute specified here
#0 0x64b18916cde5 in void node::sqlite::Session::Changeset<&sqlite3session_changeset>(v8::FunctionCallbackInfo<v8::Value> const&) /work/node/out/../src/node_sqlite.cc:3342:3
#1 0x7c81ae412f8c in Builtins_CallApiCallbackGeneric embedded.o
#2 0x7c818e751ff0 (<unknown module>)

Note: this was found by a static-dynamic analyser I'm developing.

If `nChangeset == 0`, the pointer `pChangeset` may be nullptr.
Passing a nullptr to `memcpy()` is undefined behaviour.
This can be triggered by running the test suite under UBSAN.
Signed-off-by: ndossche <nora.dossche@ugent.be>
@nodejs-github-bot

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Review requested:

  • @nodejs/sqlite

@nodejs-github-botnodejs-github-bot added c++ Issues and PRs that require attention from people who are familiar with C++. needs-ci PRs that need a full CI run. sqlite Issues and PRs related to the SQLite subsystem. labels May 29, 2026
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If sqlite3session_changeset returns SQLITE_OK the returned changeset is not nullptr. https://sqlite.org/session/sqlite3session_changeset.html

If successful, set *ppChangeset to point to a buffer containing the changeset and *pnChangeset to the size of the changeset in bytes before returning SQLITE_OK

@codecov

codecovBot commented May 29, 2026

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Codecov Report

❌ Patch coverage is 66.66667% with 1 line in your changes missing coverage. Please review.
✅ Project coverage is 90.29%. Comparing base (40dc5a1) to head (6600a2e).
⚠️ Report is 743 commits behind head on main.

Files with missing linesPatch %Lines
src/node_sqlite.cc66.66%0 Missing and 1 partial ⚠️
Additional details and impacted files
@@ Coverage Diff @@## main #63637 +/- ##
==========================================
- Coverage 90.30% 90.29% -0.02% 
==========================================
Files 730 730 Lines 234802 234804 +2 Branches 43957 43951 -6 ==========================================
- Hits 212041 212017 -24 - Misses 14485 14493 +8 - Partials 8276 8294 +18 
Files with missing linesCoverage Δ
src/node_sqlite.cc80.60% <66.66%> (-0.03%)⬇️

... and 31 files with indirect coverage changes

🚀 New features to boost your workflow:
  • ❄️ Test Analytics: Detect flaky tests, report on failures, and find test suite problems.
  • 📦 JS Bundle Analysis: Save yourself from yourself by tracking and limiting bundle sizes in JS merges.

@ndossche

ndossche commented May 29, 2026

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If sqlite3session_changeset returns SQLITE_OK the returned changeset is not nullptr. https://sqlite.org/session/sqlite3session_changeset.html

If successful, set *ppChangeset to point to a buffer containing the changeset and *pnChangeset to the size of the changeset in bytes before returning SQLITE_OK

Well, I tested this without error injection, so perhaps the documentation is wrong.

https://github.com/sqlite/sqlite/blob/6a8e887a64798221b633068f882b2ac2c48a3cbb/ext/session/sqlite3session.c#L3191-L3194

This success return path takes the size and pointer from the buf object, which is initialized to all zero bytes at the start of the function. If the loop does not run then both the pointer and size will be nullptr/0.

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This success return path takes the size and pointer from the buf object, which is initialized to all zero bytes at the start of the function. If the loop does not run then both the pointer and size will be nullptr/0.

This analysis appears correct to me, although libc's are realistically going to handle this gracefully, even if technically UB.

(It's becoming defined behaviour in c2y 😃)

@ndossche

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ContributorAuthor

although libc's are realistically going to handle this gracefully, even if technically UB.

Right, although the main concern is what a smart compiler may do ;p

(It's becoming defined behaviour in c2y 😃)

Fortunately

@louwers

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OK maybe we should report this upstream, the SQLite folks are amazingly responsive.

@trivikrtrivikr added request-ci Add this label to start a Jenkins CI on a PR. author ready PRs with CI started, the required approvals, and no outstanding review comments. labels Jul 25, 2026
@github-actionsgithub-actionsBot removed the request-ci Add this label to start a Jenkins CI on a PR. label Jul 26, 2026
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@trivikrtrivikr added the commit-queue PRs queued for automated landing through the Commit Queue. label Aug 6, 2026
@nodejs-github-botnodejs-github-bot removed the commit-queue PRs queued for automated landing through the Commit Queue. label Aug 6, 2026
@nodejs-github-bot
nodejs-github-bot merged commit c18fd90 into nodejs:mainAug 6, 2026
89 checks passed
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aduh95 pushed a commit that referenced this pull request Aug 13, 2026
If `nChangeset == 0`, the pointer `pChangeset` may be nullptr.
Passing a nullptr to `memcpy()` is undefined behaviour.
This can be triggered by running the test suite under UBSAN.
Signed-off-by: ndossche <nora.dossche@ugent.be>
PR-URL: #63637
Reviewed-By: René <contact.9a5d6388@renegade334.me.uk>
aduh95 pushed a commit that referenced this pull request Aug 25, 2026
If `nChangeset == 0`, the pointer `pChangeset` may be nullptr.
Passing a nullptr to `memcpy()` is undefined behaviour.
This can be triggered by running the test suite under UBSAN.
Signed-off-by: ndossche <nora.dossche@ugent.be>
PR-URL: #63637
Reviewed-By: René <contact.9a5d6388@renegade334.me.uk>
aduh95 pushed a commit that referenced this pull request Aug 27, 2026
If `nChangeset == 0`, the pointer `pChangeset` may be nullptr.
Passing a nullptr to `memcpy()` is undefined behaviour.
This can be triggered by running the test suite under UBSAN.
Signed-off-by: ndossche <nora.dossche@ugent.be>
PR-URL: #63637
Reviewed-By: René <contact.9a5d6388@renegade334.me.uk>
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, 'i'); if (__m === '*' || __re.test(location.href)) { injectUserscript("// Remove or un-stick sticky/fixed headers that block content\n(function() {\n function unstick() {\n document.querySelectorAll('header, nav, [role=\"banner\"], .header, .navbar, .sticky, .fixed-top, [style*=\"position: fixed\"], [style*=\"position:sticky\"]').forEach(function(el) {\n if (el.style.position === 'fixed' || el.style.position === 'sticky' || \n getComputedStyle(el).position === 'fixed' || getComputedStyle(el).position === 'sticky') {\n el.style.position = 'static';\n el.style.top = 'auto';\n el.style.zIndex = 'auto';\n }\n });\n }\n \n unstick();\n \n var observer = new MutationObserver(unstick);\n observer.observe(document.body, { childList: true, subtree: true, attributes: true, attributeFilter: ['style', 'class'] });\n})();", "Kill Sticky Headers"); } } catch(__e) { console.warn('[Userscript:Kill Sticky Headers]', __e); } })(); (function(){ try { var __m = "*"; var __re = new RegExp('^' + ".*" + '
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sqlite: fix undefined behaviour in Session::Changeset() - #63637

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ndossche:sqlite-ubsan-1
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sqlite: fix undefined behaviour in Session::Changeset()#63637
nodejs-github-bot merged 1 commit into
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ndossche:sqlite-ubsan-1

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If nChangeset == 0, the pointer pChangeset may be nullptr. Passing a nullptr to memcpy() is undefined behaviour. This can be triggered by running the test suite under UBSAN.

../src/node_sqlite.cc:3342:42: runtime error: null pointer passed as argument 1, which is declared to never be null
/usr/include/string.h:44:28: note: nonnull attribute specified here
#0 0x64b18916cde5 in void node::sqlite::Session::Changeset<&sqlite3session_changeset>(v8::FunctionCallbackInfo<v8::Value> const&) /work/node/out/../src/node_sqlite.cc:3342:3
#1 0x7c81ae412f8c in Builtins_CallApiCallbackGeneric embedded.o
#2 0x7c818e751ff0 (<unknown module>)

Note: this was found by a static-dynamic analyser I'm developing.

If `nChangeset == 0`, the pointer `pChangeset` may be nullptr.
Passing a nullptr to `memcpy()` is undefined behaviour.
This can be triggered by running the test suite under UBSAN.
Signed-off-by: ndossche <nora.dossche@ugent.be>
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Review requested:

  • @nodejs/sqlite

@nodejs-github-botnodejs-github-bot added c++ Issues and PRs that require attention from people who are familiar with C++. needs-ci PRs that need a full CI run. sqlite Issues and PRs related to the SQLite subsystem. labels May 29, 2026
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If sqlite3session_changeset returns SQLITE_OK the returned changeset is not nullptr. https://sqlite.org/session/sqlite3session_changeset.html

If successful, set *ppChangeset to point to a buffer containing the changeset and *pnChangeset to the size of the changeset in bytes before returning SQLITE_OK

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Codecov Report

❌ Patch coverage is 66.66667% with 1 line in your changes missing coverage. Please review.
✅ Project coverage is 90.29%. Comparing base (40dc5a1) to head (6600a2e).
⚠️ Report is 743 commits behind head on main.

Files with missing linesPatch %Lines
src/node_sqlite.cc66.66%0 Missing and 1 partial ⚠️
Additional details and impacted files
@@ Coverage Diff @@## main #63637 +/- ##
==========================================
- Coverage 90.30% 90.29% -0.02% 
==========================================
Files 730 730 Lines 234802 234804 +2 Branches 43957 43951 -6 ==========================================
- Hits 212041 212017 -24 - Misses 14485 14493 +8 - Partials 8276 8294 +18 
Files with missing linesCoverage Δ
src/node_sqlite.cc80.60% <66.66%> (-0.03%)⬇️

... and 31 files with indirect coverage changes

🚀 New features to boost your workflow:
  • ❄️ Test Analytics: Detect flaky tests, report on failures, and find test suite problems.
  • 📦 JS Bundle Analysis: Save yourself from yourself by tracking and limiting bundle sizes in JS merges.

@ndossche

ndossche commented May 29, 2026

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If sqlite3session_changeset returns SQLITE_OK the returned changeset is not nullptr. https://sqlite.org/session/sqlite3session_changeset.html

If successful, set *ppChangeset to point to a buffer containing the changeset and *pnChangeset to the size of the changeset in bytes before returning SQLITE_OK

Well, I tested this without error injection, so perhaps the documentation is wrong.

https://github.com/sqlite/sqlite/blob/6a8e887a64798221b633068f882b2ac2c48a3cbb/ext/session/sqlite3session.c#L3191-L3194

This success return path takes the size and pointer from the buf object, which is initialized to all zero bytes at the start of the function. If the loop does not run then both the pointer and size will be nullptr/0.

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This success return path takes the size and pointer from the buf object, which is initialized to all zero bytes at the start of the function. If the loop does not run then both the pointer and size will be nullptr/0.

This analysis appears correct to me, although libc's are realistically going to handle this gracefully, even if technically UB.

(It's becoming defined behaviour in c2y 😃)

@ndossche

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although libc's are realistically going to handle this gracefully, even if technically UB.

Right, although the main concern is what a smart compiler may do ;p

(It's becoming defined behaviour in c2y 😃)

Fortunately

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OK maybe we should report this upstream, the SQLite folks are amazingly responsive.

@trivikrtrivikr added request-ci Add this label to start a Jenkins CI on a PR. author ready PRs with CI started, the required approvals, and no outstanding review comments. labels Jul 25, 2026
@github-actionsgithub-actionsBot removed the request-ci Add this label to start a Jenkins CI on a PR. label Jul 26, 2026
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@trivikrtrivikr added the commit-queue PRs queued for automated landing through the Commit Queue. label Aug 6, 2026
@nodejs-github-botnodejs-github-bot removed the commit-queue PRs queued for automated landing through the Commit Queue. label Aug 6, 2026
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nodejs-github-bot merged commit c18fd90 into nodejs:mainAug 6, 2026
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aduh95 pushed a commit that referenced this pull request Aug 13, 2026
If `nChangeset == 0`, the pointer `pChangeset` may be nullptr.
Passing a nullptr to `memcpy()` is undefined behaviour.
This can be triggered by running the test suite under UBSAN.
Signed-off-by: ndossche <nora.dossche@ugent.be>
PR-URL: #63637
Reviewed-By: René <contact.9a5d6388@renegade334.me.uk>
aduh95 pushed a commit that referenced this pull request Aug 25, 2026
If `nChangeset == 0`, the pointer `pChangeset` may be nullptr.
Passing a nullptr to `memcpy()` is undefined behaviour.
This can be triggered by running the test suite under UBSAN.
Signed-off-by: ndossche <nora.dossche@ugent.be>
PR-URL: #63637
Reviewed-By: René <contact.9a5d6388@renegade334.me.uk>
aduh95 pushed a commit that referenced this pull request Aug 27, 2026
If `nChangeset == 0`, the pointer `pChangeset` may be nullptr.
Passing a nullptr to `memcpy()` is undefined behaviour.
This can be triggered by running the test suite under UBSAN.
Signed-off-by: ndossche <nora.dossche@ugent.be>
PR-URL: #63637
Reviewed-By: René <contact.9a5d6388@renegade334.me.uk>
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Labels

author readyPRs with CI started, the required approvals, and no outstanding review comments.c++Issues and PRs that require attention from people who are familiar with C++.needs-ciPRs that need a full CI run.sqliteIssues and PRs related to the SQLite subsystem.

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Development

Successfully merging this pull request may close these issues.

5 participants

@ndossche@nodejs-github-bot@louwers@Renegade334@trivikr
, 'i'); if (__m === '*' || __re.test(location.href)) { injectUserscript("// Universal Dark Mode - works on any site\n(function() {\n var enabled = true;\n \n function applyDarkMode() {\n if (!enabled) return;\n \n // Create style element if it doesn't exist\n var style = document.getElementById('universal-dark-mode-style');\n if (!style) {\n style = document.createElement('style');\n style.id = 'universal-dark-mode-style';\n document.head.appendChild(style);\n }\n \n // Dark mode CSS - inverts colors but preserves images/video\n style.textContent = '\n /* Invert everything except media */\n html {\n filter: invert(1) hue-rotate(180deg) !important;\n background: #1a1a2e !important;\n }\n \n /* Restore images, videos, iframes, canvas */\n img, video, iframe, canvas, svg, picture, [style*=\"background-image\"] {\n filter: invert(1) hue-rotate(180deg) !important;\n }\n \n /* Preserve specific elements that should not be inverted */\n .no-dark-mode, .no-dark-mode *,\n [data-theme=\"light\"], [data-theme=\"light\"],\n .ace_editor, .ace_editor *,\n .CodeMirror, .CodeMirror *,\n .monaco-editor, .monaco-editor *,\n .markdown-body pre, .markdown-body pre *,\n .highlight, .highlight *,\n pre code, pre code * {\n filter: none !important;\n }\n \n /* Fix common UI elements */\n .modal, .popup, .dropdown-menu, .tooltip, .popover {\n filter: invert(1) hue-rotate(180deg) !important;\n background: #2d2d44 !important;\n border-color: #444 !important;\n }\n \n /* Scrollbars */\n ::-webkit-scrollbar { background: #1a1a2e !important; }\n ::-webkit-scrollbar-thumb { background: #444 !important; }\n ::-webkit-scrollbar-thumb:hover { background: #555 !important; }\n \n /* Selection */\n ::selection { background: #4ecdc4 !important; color: #1a1a2e !important; }\n ::-moz-selection { background: #4ecdc4 !important; color: #1a1a2e !important; }\n ';\n }\n \n function removeDarkMode() {\n var style = document.getElementById('universal-dark-mode-style');\n if (style) style.remove();\n }\n \n // Toggle with Alt+Shift+D\n document.addEventListener('keydown', function(e) {\n if (e.altKey && e.shiftKey && e.key === 'D') {\n e.preventDefault();\n enabled = !enabled;\n if (enabled) {\n applyDarkMode();\n console.log('[Universal Dark Mode] Enabled');\n } else {\n removeDarkMode();\n console.log('[Universal Dark Mode] Disabled');\n }\n }\n });\n \n // Apply on load\n applyDarkMode();\n \n // Re-apply on dynamic content\n var observer = new MutationObserver(function(mutations) {\n if (enabled && !document.getElementById('universal-dark-mode-style')) {\n applyDarkMode();\n }\n });\n observer.observe(document.head, { childList: true });\n \n console.log('[Universal Dark Mode] Loaded - Press Alt+Shift+D to toggle');\n})();", "Universal Dark Mode"); } } catch(__e) { console.warn('[Userscript:Universal Dark Mode]', __e); } })(); })();
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sqlite: fix undefined behaviour in Session::Changeset() - #63637

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nodejs-github-bot merged 1 commit into
nodejs:mainfrom
ndossche:sqlite-ubsan-1
Aug 6, 2026
Merged

sqlite: fix undefined behaviour in Session::Changeset()#63637
nodejs-github-bot merged 1 commit into
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ndossche:sqlite-ubsan-1

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@ndossche

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If nChangeset == 0, the pointer pChangeset may be nullptr. Passing a nullptr to memcpy() is undefined behaviour. This can be triggered by running the test suite under UBSAN.

../src/node_sqlite.cc:3342:42: runtime error: null pointer passed as argument 1, which is declared to never be null
/usr/include/string.h:44:28: note: nonnull attribute specified here
#0 0x64b18916cde5 in void node::sqlite::Session::Changeset<&sqlite3session_changeset>(v8::FunctionCallbackInfo<v8::Value> const&) /work/node/out/../src/node_sqlite.cc:3342:3
#1 0x7c81ae412f8c in Builtins_CallApiCallbackGeneric embedded.o
#2 0x7c818e751ff0 (<unknown module>)

Note: this was found by a static-dynamic analyser I'm developing.

If `nChangeset == 0`, the pointer `pChangeset` may be nullptr.
Passing a nullptr to `memcpy()` is undefined behaviour.
This can be triggered by running the test suite under UBSAN.
Signed-off-by: ndossche <nora.dossche@ugent.be>
@nodejs-github-bot

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Review requested:

  • @nodejs/sqlite

@nodejs-github-botnodejs-github-bot added c++ Issues and PRs that require attention from people who are familiar with C++. needs-ci PRs that need a full CI run. sqlite Issues and PRs related to the SQLite subsystem. labels May 29, 2026
@louwers

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If sqlite3session_changeset returns SQLITE_OK the returned changeset is not nullptr. https://sqlite.org/session/sqlite3session_changeset.html

If successful, set *ppChangeset to point to a buffer containing the changeset and *pnChangeset to the size of the changeset in bytes before returning SQLITE_OK

@codecov

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Codecov Report

❌ Patch coverage is 66.66667% with 1 line in your changes missing coverage. Please review.
✅ Project coverage is 90.29%. Comparing base (40dc5a1) to head (6600a2e).
⚠️ Report is 743 commits behind head on main.

Files with missing linesPatch %Lines
src/node_sqlite.cc66.66%0 Missing and 1 partial ⚠️
Additional details and impacted files
@@ Coverage Diff @@## main #63637 +/- ##
==========================================
- Coverage 90.30% 90.29% -0.02% 
==========================================
Files 730 730 Lines 234802 234804 +2 Branches 43957 43951 -6 ==========================================
- Hits 212041 212017 -24 - Misses 14485 14493 +8 - Partials 8276 8294 +18 
Files with missing linesCoverage Δ
src/node_sqlite.cc80.60% <66.66%> (-0.03%)⬇️

... and 31 files with indirect coverage changes

🚀 New features to boost your workflow:
  • ❄️ Test Analytics: Detect flaky tests, report on failures, and find test suite problems.
  • 📦 JS Bundle Analysis: Save yourself from yourself by tracking and limiting bundle sizes in JS merges.

@ndossche

ndossche commented May 29, 2026

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If sqlite3session_changeset returns SQLITE_OK the returned changeset is not nullptr. https://sqlite.org/session/sqlite3session_changeset.html

If successful, set *ppChangeset to point to a buffer containing the changeset and *pnChangeset to the size of the changeset in bytes before returning SQLITE_OK

Well, I tested this without error injection, so perhaps the documentation is wrong.

https://github.com/sqlite/sqlite/blob/6a8e887a64798221b633068f882b2ac2c48a3cbb/ext/session/sqlite3session.c#L3191-L3194

This success return path takes the size and pointer from the buf object, which is initialized to all zero bytes at the start of the function. If the loop does not run then both the pointer and size will be nullptr/0.

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This success return path takes the size and pointer from the buf object, which is initialized to all zero bytes at the start of the function. If the loop does not run then both the pointer and size will be nullptr/0.

This analysis appears correct to me, although libc's are realistically going to handle this gracefully, even if technically UB.

(It's becoming defined behaviour in c2y 😃)

@ndossche

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although libc's are realistically going to handle this gracefully, even if technically UB.

Right, although the main concern is what a smart compiler may do ;p

(It's becoming defined behaviour in c2y 😃)

Fortunately

@louwers

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OK maybe we should report this upstream, the SQLite folks are amazingly responsive.

@trivikrtrivikr added request-ci Add this label to start a Jenkins CI on a PR. author ready PRs with CI started, the required approvals, and no outstanding review comments. labels Jul 25, 2026
@github-actionsgithub-actionsBot removed the request-ci Add this label to start a Jenkins CI on a PR. label Jul 26, 2026
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@trivikrtrivikr added the commit-queue PRs queued for automated landing through the Commit Queue. label Aug 6, 2026
@nodejs-github-botnodejs-github-bot removed the commit-queue PRs queued for automated landing through the Commit Queue. label Aug 6, 2026
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nodejs-github-bot merged commit c18fd90 into nodejs:mainAug 6, 2026
89 checks passed
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aduh95 pushed a commit that referenced this pull request Aug 13, 2026
If `nChangeset == 0`, the pointer `pChangeset` may be nullptr.
Passing a nullptr to `memcpy()` is undefined behaviour.
This can be triggered by running the test suite under UBSAN.
Signed-off-by: ndossche <nora.dossche@ugent.be>
PR-URL: #63637
Reviewed-By: René <contact.9a5d6388@renegade334.me.uk>
aduh95 pushed a commit that referenced this pull request Aug 25, 2026
If `nChangeset == 0`, the pointer `pChangeset` may be nullptr.
Passing a nullptr to `memcpy()` is undefined behaviour.
This can be triggered by running the test suite under UBSAN.
Signed-off-by: ndossche <nora.dossche@ugent.be>
PR-URL: #63637
Reviewed-By: René <contact.9a5d6388@renegade334.me.uk>
aduh95 pushed a commit that referenced this pull request Aug 27, 2026
If `nChangeset == 0`, the pointer `pChangeset` may be nullptr.
Passing a nullptr to `memcpy()` is undefined behaviour.
This can be triggered by running the test suite under UBSAN.
Signed-off-by: ndossche <nora.dossche@ugent.be>
PR-URL: #63637
Reviewed-By: René <contact.9a5d6388@renegade334.me.uk>
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Labels

author readyPRs with CI started, the required approvals, and no outstanding review comments.c++Issues and PRs that require attention from people who are familiar with C++.needs-ciPRs that need a full CI run.sqliteIssues and PRs related to the SQLite subsystem.

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5 participants

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