From: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Date: Mon, 19 Feb 2024 20:03:24 +0000 (+0100)
Subject: 5.10-stable patches
X-Git-Tag: v4.19.307~94
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=e275d11b0d1d524852830d1d81880b40a098f449;p=thirdparty%2Fkernel%2Fstable-queue.git

5.10-stable patches

added patches:
	tracing-inform-kmemleak-of-saved_cmdlines-allocation.patch
---

diff --git a/queue-5.10/series b/queue-5.10/series
index 804b0263fdb..7267225166a 100644
--- a/queue-5.10/series
+++ b/queue-5.10/series
@@ -347,3 +347,4 @@ ceph-prevent-use-after-free-in-encode_cap_msg.patch
 of-property-fix-typo-in-io-channels.patch
 can-j1939-fix-uaf-in-j1939_sk_match_filter-during-setsockopt-so_j1939_filter.patch
 pmdomain-core-move-the-unused-cleanup-to-a-_sync-initcall.patch
+tracing-inform-kmemleak-of-saved_cmdlines-allocation.patch
diff --git a/queue-5.10/tracing-inform-kmemleak-of-saved_cmdlines-allocation.patch b/queue-5.10/tracing-inform-kmemleak-of-saved_cmdlines-allocation.patch
new file mode 100644
index 00000000000..37d9ca3cce9
--- /dev/null
+++ b/queue-5.10/tracing-inform-kmemleak-of-saved_cmdlines-allocation.patch
@@ -0,0 +1,94 @@
+From 2394ac4145ea91b92271e675a09af2a9ea6840b7 Mon Sep 17 00:00:00 2001
+From: "Steven Rostedt (Google)" <rostedt@goodmis.org>
+Date: Wed, 14 Feb 2024 11:20:46 -0500
+Subject: tracing: Inform kmemleak of saved_cmdlines allocation
+
+From: Steven Rostedt (Google) <rostedt@goodmis.org>
+
+commit 2394ac4145ea91b92271e675a09af2a9ea6840b7 upstream.
+
+The allocation of the struct saved_cmdlines_buffer structure changed from:
+
+        s = kmalloc(sizeof(*s), GFP_KERNEL);
+	s->saved_cmdlines = kmalloc_array(TASK_COMM_LEN, val, GFP_KERNEL);
+
+to:
+
+	orig_size = sizeof(*s) + val * TASK_COMM_LEN;
+	order = get_order(orig_size);
+	size = 1 << (order + PAGE_SHIFT);
+	page = alloc_pages(GFP_KERNEL, order);
+	if (!page)
+		return NULL;
+
+	s = page_address(page);
+	memset(s, 0, sizeof(*s));
+
+	s->saved_cmdlines = kmalloc_array(TASK_COMM_LEN, val, GFP_KERNEL);
+
+Where that s->saved_cmdlines allocation looks to be a dangling allocation
+to kmemleak. That's because kmemleak only keeps track of kmalloc()
+allocations. For allocations that use page_alloc() directly, the kmemleak
+needs to be explicitly informed about it.
+
+Add kmemleak_alloc() and kmemleak_free() around the page allocation so
+that it doesn't give the following false positive:
+
+unreferenced object 0xffff8881010c8000 (size 32760):
+  comm "swapper", pid 0, jiffies 4294667296
+  hex dump (first 32 bytes):
+    ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff  ................
+    ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff  ................
+  backtrace (crc ae6ec1b9):
+    [<ffffffff86722405>] kmemleak_alloc+0x45/0x80
+    [<ffffffff8414028d>] __kmalloc_large_node+0x10d/0x190
+    [<ffffffff84146ab1>] __kmalloc+0x3b1/0x4c0
+    [<ffffffff83ed7103>] allocate_cmdlines_buffer+0x113/0x230
+    [<ffffffff88649c34>] tracer_alloc_buffers.isra.0+0x124/0x460
+    [<ffffffff8864a174>] early_trace_init+0x14/0xa0
+    [<ffffffff885dd5ae>] start_kernel+0x12e/0x3c0
+    [<ffffffff885f5758>] x86_64_start_reservations+0x18/0x30
+    [<ffffffff885f582b>] x86_64_start_kernel+0x7b/0x80
+    [<ffffffff83a001c3>] secondary_startup_64_no_verify+0x15e/0x16b
+
+Link: https://lore.kernel.org/linux-trace-kernel/87r0hfnr9r.fsf@kernel.org/
+Link: https://lore.kernel.org/linux-trace-kernel/20240214112046.09a322d6@gandalf.local.home
+
+Cc: Masami Hiramatsu <mhiramat@kernel.org>
+Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
+Cc: Catalin Marinas <catalin.marinas@arm.com>
+Fixes: 44dc5c41b5b1 ("tracing: Fix wasted memory in saved_cmdlines logic")
+Reported-by: Kalle Valo <kvalo@kernel.org>
+Tested-by: Kalle Valo <kvalo@kernel.org>
+Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+---
+ kernel/trace/trace.c |    3 +++
+ 1 file changed, 3 insertions(+)
+
+--- a/kernel/trace/trace.c
++++ b/kernel/trace/trace.c
+@@ -39,6 +39,7 @@
+ #include <linux/slab.h>
+ #include <linux/ctype.h>
+ #include <linux/init.h>
++#include <linux/kmemleak.h>
+ #include <linux/poll.h>
+ #include <linux/nmi.h>
+ #include <linux/fs.h>
+@@ -2258,6 +2259,7 @@ static void free_saved_cmdlines_buffer(s
+ 	int order = get_order(sizeof(*s) + s->cmdline_num * TASK_COMM_LEN);
+ 
+ 	kfree(s->map_cmdline_to_pid);
++	kmemleak_free(s);
+ 	free_pages((unsigned long)s, order);
+ }
+ 
+@@ -2277,6 +2279,7 @@ static struct saved_cmdlines_buffer *all
+ 		return NULL;
+ 
+ 	s = page_address(page);
++	kmemleak_alloc(s, size, 1, GFP_KERNEL);
+ 	memset(s, 0, sizeof(*s));
+ 
+ 	/* Round up to actual allocation */