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 908944315A; Sun, 7 Sep 2025 20:36:50 +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=1757277410; cv=none; b=HEwXmqbChbBDcMVm4PFhKLZjFUC3tPAGZxTWEWVjAmoW15PcVvuOz1jMLnV/E9T0dcOJpEBHqfhe3qUIiTeKfKzsjRIYRSvh+8APWQ7PI1e0Of+07OAbzQqNOfbHuteedZ1IkSo/YuBDktdiRkUX+XHI5yxvHPsQ4YifXf+UJNs= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1757277410; c=relaxed/simple; bh=vRHH4DYwVEEEZPqglbwfhAivtUuHXF2zMw6Uy6sg9WM=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=nbePltd6mI5HTBcLPejKpgzke91ymxoDKwCS7ZASKu2gqbQ83gbyehVIEyEDCABR4ijv7pjVCgGNhCOTrKBVk87nm49PUdt+i7xMBusXPE4xXOT09w5NtcyS/vh3hVvW2zgzvYSFP9HpQ6WKL/M6/EnA/QRMXRoVBhVOv+thVic= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=aUbo8bB0; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="aUbo8bB0" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 1B831C4CEF0; Sun, 7 Sep 2025 20:36:49 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1757277410; bh=vRHH4DYwVEEEZPqglbwfhAivtUuHXF2zMw6Uy6sg9WM=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=aUbo8bB0sVaqcGCEK2vdufDUag5ONsIr8U8t8PfzunKBJ6Sw2y4CzRrODNur9lHY9 dzE39pzL0XFLms54OuowQEg5nElyCUVmaXBBx17ZxA1By9EPbPn5iQFhOXsy/lTlhe ZzKLmJJbzep5r4gobunEcWkAN6KowBozoJW3E2G8= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Vlastimil Babka , Harry Yoo , Sasha Levin Subject: [PATCH 6.12 139/175] mm, slab: cleanup slab_bug() parameters Date: Sun, 7 Sep 2025 21:58:54 +0200 Message-ID: <20250907195618.138904857@linuxfoundation.org> X-Mailer: git-send-email 2.51.0 In-Reply-To: <20250907195614.892725141@linuxfoundation.org> References: <20250907195614.892725141@linuxfoundation.org> User-Agent: quilt/0.68 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.12-stable review patch. If anyone has any objections, please let me know. ------------------ From: Vlastimil Babka [ Upstream commit 4b183dd9359d5772446cb634b12a383bed98c4fc ] slab_err() has variadic printf arguments but instead of passing them to slab_bug() it does vsnprintf() to a buffer and passes %s, buf. To allow passing them directly, turn slab_bug() to __slab_bug() with a va_list parameter, and slab_bug() a wrapper with fmt, ... parameters. Then slab_err() can call __slab_bug() without the intermediate buffer. Also constify fmt everywhere, which also simplifies object_err()'s call to slab_bug(). Signed-off-by: Vlastimil Babka Reviewed-by: Harry Yoo Stable-dep-of: b4efccec8d06 ("mm/slub: avoid accessing metadata when pointer is invalid in object_err()") Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman --- mm/slub.c | 28 ++++++++++++++++++---------- 1 file changed, 18 insertions(+), 10 deletions(-) --- a/mm/slub.c +++ b/mm/slub.c @@ -1027,12 +1027,12 @@ void skip_orig_size_check(struct kmem_ca set_orig_size(s, (void *)object, s->object_size); } -static void slab_bug(struct kmem_cache *s, char *fmt, ...) +static void __slab_bug(struct kmem_cache *s, const char *fmt, va_list argsp) { struct va_format vaf; va_list args; - va_start(args, fmt); + va_copy(args, argsp); vaf.fmt = fmt; vaf.va = &args; pr_err("=============================================================================\n"); @@ -1041,8 +1041,17 @@ static void slab_bug(struct kmem_cache * va_end(args); } +static void slab_bug(struct kmem_cache *s, const char *fmt, ...) +{ + va_list args; + + va_start(args, fmt); + __slab_bug(s, fmt, args); + va_end(args); +} + __printf(2, 3) -static void slab_fix(struct kmem_cache *s, char *fmt, ...) +static void slab_fix(struct kmem_cache *s, const char *fmt, ...) { struct va_format vaf; va_list args; @@ -1098,12 +1107,12 @@ static void print_trailer(struct kmem_ca } static void object_err(struct kmem_cache *s, struct slab *slab, - u8 *object, char *reason) + u8 *object, const char *reason) { if (slab_add_kunit_errors()) return; - slab_bug(s, "%s", reason); + slab_bug(s, reason); print_trailer(s, slab, object); add_taint(TAINT_BAD_PAGE, LOCKDEP_NOW_UNRELIABLE); @@ -1139,15 +1148,14 @@ static __printf(3, 4) void slab_err(stru const char *fmt, ...) { va_list args; - char buf[100]; if (slab_add_kunit_errors()) return; va_start(args, fmt); - vsnprintf(buf, sizeof(buf), fmt, args); + __slab_bug(s, fmt, args); va_end(args); - slab_bug(s, "%s", buf); + __slab_err(slab); } @@ -1185,7 +1193,7 @@ static void init_object(struct kmem_cach s->inuse - poison_size); } -static void restore_bytes(struct kmem_cache *s, char *message, u8 data, +static void restore_bytes(struct kmem_cache *s, const char *message, u8 data, void *from, void *to) { slab_fix(s, "Restoring %s 0x%p-0x%p=0x%x", message, from, to - 1, data); @@ -1200,7 +1208,7 @@ static void restore_bytes(struct kmem_ca static pad_check_attributes int check_bytes_and_report(struct kmem_cache *s, struct slab *slab, - u8 *object, char *what, u8 *start, unsigned int value, + u8 *object, const char *what, u8 *start, unsigned int value, unsigned int bytes, bool slab_obj_print) { u8 *fault;