Date: Fri, 31 Jul 2026 15:54:52 +0000 From: Adrian Chadd <adrian@FreeBSD.org> To: src-committers@FreeBSD.org, dev-commits-src-all@FreeBSD.org, dev-commits-src-main@FreeBSD.org Cc: Abdelkader Boudih <freebsd@seuros.com> Subject: git: ff97443beef6 - main - kqueue: do not buffer the whole knote report when sizing it Message-ID: <6a6cc54c.32695.765f48cb@gitrepo.freebsd.org>
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The branch main has been updated by adrian: URL: https://cgit.FreeBSD.org/src/commit/?id=ff97443beef614a12652cb96ccebe95e9046e82a commit ff97443beef614a12652cb96ccebe95e9046e82a Author: Abdelkader Boudih <freebsd@seuros.com> AuthorDate: 2026-07-31 15:46:38 +0000 Commit: Adrian Chadd <adrian@FreeBSD.org> CommitDate: 2026-07-31 15:46:45 +0000 kqueue: do not buffer the whole knote report when sizing it kern_proc_kqueues_out() reported into an intermediate sbuf and copied the result into the caller's. A process that had leaked 468k kqueue descriptors wired 757 MB of M_SBUF while dumping core, over roughly 9M reallocations, then copied the whole thing again. Reviewed by: adrian, markj Differential Revision: https://reviews.freebsd.org/D58536 PR: 296835 MFC after: 1 week --- sys/kern/kern_event.c | 14 +++++++------- 1 file changed, 7 insertions(+), 7 deletions(-) diff --git a/sys/kern/kern_event.c b/sys/kern/kern_event.c index 28e31a227357..e8395707a29d 100644 --- a/sys/kern/kern_event.c +++ b/sys/kern/kern_event.c @@ -3359,18 +3359,18 @@ kern_proc_kqueues_out(struct proc *p, struct sbuf *sb, size_t maxlen, size_t sb_len; int error; - if (maxlen == -1 || maxlen == 0) + if (maxlen == -1) + return (kern_proc_kqueues_out1(curthread, p, sb, compat32)); + + if (maxlen == 0) sb_len = 128; else sb_len = maxlen; - s = sbuf_new(&sm, NULL, sb_len, maxlen == -1 ? SBUF_AUTOEXTEND : - SBUF_FIXEDLEN); + s = sbuf_new(&sm, NULL, sb_len, SBUF_FIXEDLEN); error = kern_proc_kqueues_out1(curthread, p, s, compat32); sbuf_finish(s); - if (error == 0) { - sbuf_bcat(sb, sbuf_data(s), MIN(sbuf_len(s), maxlen == -1 ? - SIZE_T_MAX : maxlen)); - } + if (error == 0) + sbuf_bcat(sb, sbuf_data(s), MIN(sbuf_len(s), maxlen)); sbuf_delete(s); return (error); }home | help
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