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Shuai Xue 2e905e608e perf/core: Bail out early if the request AUX area is out of bound
[ Upstream commit 54aee5f15b ]

When perf-record with a large AUX area, e.g 4GB, it fails with:

    #perf record -C 0 -m ,4G -e arm_spe_0// -- sleep 1
    failed to mmap with 12 (Cannot allocate memory)

and it reveals a WARNING with __alloc_pages():

	------------[ cut here ]------------
	WARNING: CPU: 44 PID: 17573 at mm/page_alloc.c:5568 __alloc_pages+0x1ec/0x248
	Call trace:
	 __alloc_pages+0x1ec/0x248
	 __kmalloc_large_node+0xc0/0x1f8
	 __kmalloc_node+0x134/0x1e8
	 rb_alloc_aux+0xe0/0x298
	 perf_mmap+0x440/0x660
	 mmap_region+0x308/0x8a8
	 do_mmap+0x3c0/0x528
	 vm_mmap_pgoff+0xf4/0x1b8
	 ksys_mmap_pgoff+0x18c/0x218
	 __arm64_sys_mmap+0x38/0x58
	 invoke_syscall+0x50/0x128
	 el0_svc_common.constprop.0+0x58/0x188
	 do_el0_svc+0x34/0x50
	 el0_svc+0x34/0x108
	 el0t_64_sync_handler+0xb8/0xc0
	 el0t_64_sync+0x1a4/0x1a8

'rb->aux_pages' allocated by kcalloc() is a pointer array which is used to
maintains AUX trace pages. The allocated page for this array is physically
contiguous (and virtually contiguous) with an order of 0..MAX_ORDER. If the
size of pointer array crosses the limitation set by MAX_ORDER, it reveals a
WARNING.

So bail out early with -ENOMEM if the request AUX area is out of bound,
e.g.:

    #perf record -C 0 -m ,4G -e arm_spe_0// -- sleep 1
    failed to mmap with 12 (Cannot allocate memory)

Signed-off-by: Shuai Xue <xueshuai@linux.alibaba.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-11-28 17:19:36 +00:00
Documentation dt-bindings: mfd: mt6397: Split out compatible for MediaTek MT6366 PMIC 2023-11-20 11:59:24 +01:00
LICENSES LICENSES: Add the copyleft-next-0.3.1 license 2022-11-08 15:44:01 +01:00
arch x86/amd_nb: Use Family 19h Models 60h-7Fh Function 4 IDs 2023-11-20 11:59:38 +01:00
block blk-core: use pr_warn_ratelimited() in bio_check_ro() 2023-11-20 11:59:36 +01:00
certs certs: Reference revocation list for all keyrings 2023-08-17 20:12:41 +00:00
crypto certs: Break circular dependency when selftest is modular 2023-11-20 11:59:23 +01:00
drivers Revert "mmc: core: Capture correct oemid-bits for eMMC cards" 2023-11-20 11:59:39 +01:00
fs btrfs: abort transaction on generation mismatch when marking eb as dirty 2023-11-28 17:19:35 +00:00
include lib/generic-radix-tree.c: Don't overflow in peek() 2023-11-28 17:19:35 +00:00
init x86/retpoline: Make sure there are no unconverted return thunks due to KCSAN 2023-11-28 17:19:36 +00:00
io_uring io_uring/net: ensure socket is marked connected on connect retry 2023-11-20 11:59:38 +01:00
ipc Add x86 shadow stack support 2023-08-31 12:20:12 -07:00
kernel perf/core: Bail out early if the request AUX area is out of bound 2023-11-28 17:19:36 +00:00
lib lib/generic-radix-tree.c: Don't overflow in peek() 2023-11-28 17:19:35 +00:00
mm vfs: fix readahead(2) on block devices 2023-11-20 11:58:52 +01:00
net net/sched: act_ct: Always fill offloading tuple iifidx 2023-11-20 11:59:37 +01:00
rust rust: docs: fix logo replacement 2023-10-19 16:40:00 +02:00
samples VFIO updates for v6.6-rc1 2023-08-30 20:36:01 -07:00
scripts x86/retpoline: Make sure there are no unconverted return thunks due to KCSAN 2023-11-28 17:19:36 +00:00
security apparmor: fix invalid reference on profile->disconnected 2023-11-20 11:59:24 +01:00
sound ALSA: hda/realtek: Add support dual speaker for Dell 2023-11-20 11:59:38 +01:00
tools selftests: mptcp: fix wait_rm_addr/sf parameters 2023-11-20 11:59:38 +01:00
usr initramfs: Encode dependency on KBUILD_BUILD_TIMESTAMP 2023-06-06 17:54:49 +09:00
virt ARM: 2023-09-07 13:52:20 -07:00
.clang-format iommu: Add for_each_group_device() 2023-05-23 08:15:51 +02:00
.cocciconfig
.get_maintainer.ignore get_maintainer: add Alan to .get_maintainer.ignore 2022-08-20 15:17:44 -07:00
.gitattributes .gitattributes: set diff driver for Rust source code files 2023-05-31 17:48:25 +02:00
.gitignore kbuild: rpm-pkg: rename binkernel.spec to kernel.spec 2023-07-25 00:59:33 +09:00
.mailmap 20 hotfixes. 12 are cc:stable and the remainder address post-6.5 issues 2023-10-24 09:52:16 -10:00
.rustfmt.toml rust: add `.rustfmt.toml` 2022-09-28 09:02:20 +02:00
COPYING COPYING: state that all contributions really are covered by this file 2020-02-10 13:32:20 -08:00
CREDITS USB: Remove Wireless USB and UWB documentation 2023-08-09 14:17:32 +02:00
Kbuild Kbuild updates for v6.1 2022-10-10 12:00:45 -07:00
Kconfig kbuild: ensure full rebuild when the compiler is updated 2020-05-12 13:28:33 +09:00
MAINTAINERS Char/Misc driver fixes for 6.6-final 2023-10-28 07:51:27 -10:00
Makefile Linux 6.6.2 2023-11-20 11:59:39 +01:00
README

README

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