From: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
To: linux-kernel@vger.kernel.org
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
stable@vger.kernel.org,
"Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>,
Borislav Petkov <bp@suse.de>, "H. Peter Anvin" <hpa@zytor.com>,
Ingo Molnar <mingo@redhat.com>,
Thomas Gleixner <tglx@linutronix.de>, x86-ml <x86@kernel.org>,
Sasha Levin <sashal@kernel.org>
Subject: [PATCH 4.19 40/57] x86/boot/compressed/64: Fix boot on machines with broken E820 table
Date: Sun, 8 Sep 2019 13:42:04 +0100 [thread overview]
Message-ID: <20190908121144.033654811@linuxfoundation.org> (raw)
In-Reply-To: <20190908121125.608195329@linuxfoundation.org>
[ Upstream commit 0a46fff2f9108c2c44218380a43a736cf4612541 ]
BIOS on Samsung 500C Chromebook reports very rudimentary E820 table that
consists of 2 entries:
BIOS-e820: [mem 0x0000000000000000-0x0000000000000fff] usable
BIOS-e820: [mem 0x00000000fffff000-0x00000000ffffffff] reserved
It breaks logic in find_trampoline_placement(): bios_start lands on the
end of the first 4k page and trampoline start gets placed below 0.
Detect underflow and don't touch bios_start for such cases. It makes
kernel ignore E820 table on machines that doesn't have two usable pages
below BIOS_START_MAX.
Fixes: 1b3a62643660 ("x86/boot/compressed/64: Validate trampoline placement against E820")
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: x86-ml <x86@kernel.org>
Link: https://bugzilla.kernel.org/show_bug.cgi?id=203463
Link: https://lkml.kernel.org/r/20190813131654.24378-1-kirill.shutemov@linux.intel.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
arch/x86/boot/compressed/pgtable_64.c | 13 ++++++++++---
1 file changed, 10 insertions(+), 3 deletions(-)
diff --git a/arch/x86/boot/compressed/pgtable_64.c b/arch/x86/boot/compressed/pgtable_64.c
index f8debf7aeb4c1..f0537a1f7fc25 100644
--- a/arch/x86/boot/compressed/pgtable_64.c
+++ b/arch/x86/boot/compressed/pgtable_64.c
@@ -73,6 +73,8 @@ static unsigned long find_trampoline_placement(void)
/* Find the first usable memory region under bios_start. */
for (i = boot_params->e820_entries - 1; i >= 0; i--) {
+ unsigned long new;
+
entry = &boot_params->e820_table[i];
/* Skip all entries above bios_start. */
@@ -85,15 +87,20 @@ static unsigned long find_trampoline_placement(void)
/* Adjust bios_start to the end of the entry if needed. */
if (bios_start > entry->addr + entry->size)
- bios_start = entry->addr + entry->size;
+ new = entry->addr + entry->size;
/* Keep bios_start page-aligned. */
- bios_start = round_down(bios_start, PAGE_SIZE);
+ new = round_down(new, PAGE_SIZE);
/* Skip the entry if it's too small. */
- if (bios_start - TRAMPOLINE_32BIT_SIZE < entry->addr)
+ if (new - TRAMPOLINE_32BIT_SIZE < entry->addr)
continue;
+ /* Protect against underflow. */
+ if (new - TRAMPOLINE_32BIT_SIZE > bios_start)
+ break;
+
+ bios_start = new;
break;
}
--
2.20.1
next prev parent reply other threads:[~2019-09-08 12:56 UTC|newest]
Thread overview: 69+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-09-08 12:41 [PATCH 4.19 00/57] 4.19.72-stable review Greg Kroah-Hartman
2019-09-08 12:41 ` [PATCH 4.19 01/57] mld: fix memory leak in mld_del_delrec() Greg Kroah-Hartman
2019-09-08 12:41 ` [PATCH 4.19 02/57] net: fix skb use after free in netpoll Greg Kroah-Hartman
2019-09-08 12:41 ` [PATCH 4.19 03/57] net: sched: act_sample: fix psample group handling on overwrite Greg Kroah-Hartman
2019-09-08 12:41 ` [PATCH 4.19 04/57] net_sched: fix a NULL pointer deref in ipt action Greg Kroah-Hartman
2019-09-08 12:41 ` [PATCH 4.19 05/57] net: stmmac: dwmac-rk: Dont fail if phy regulator is absent Greg Kroah-Hartman
2019-09-08 12:41 ` [PATCH 4.19 06/57] tcp: inherit timestamp on mtu probe Greg Kroah-Hartman
2019-09-08 12:41 ` [PATCH 4.19 07/57] tcp: remove empty skb from write queue in error cases Greg Kroah-Hartman
2019-09-08 12:41 ` [PATCH 4.19 08/57] net/rds: Fix info leak in rds6_inc_info_copy() Greg Kroah-Hartman
2019-09-08 12:41 ` [PATCH 4.19 09/57] x86/boot: Preserve boot_params.secure_boot from sanitizing Greg Kroah-Hartman
2019-09-08 12:41 ` [PATCH 4.19 10/57] spi: bcm2835aux: unifying code between polling and interrupt driven code Greg Kroah-Hartman
2019-09-08 12:41 ` [PATCH 4.19 11/57] spi: bcm2835aux: remove dangerous uncontrolled read of fifo Greg Kroah-Hartman
2019-09-08 12:41 ` [PATCH 4.19 12/57] spi: bcm2835aux: fix corruptions for longer spi transfers Greg Kroah-Hartman
2019-09-08 12:41 ` [PATCH 4.19 13/57] net: tundra: tsi108: use spin_lock_irqsave instead of spin_lock_irq in IRQ context Greg Kroah-Hartman
2019-09-08 12:41 ` [PATCH 4.19 14/57] netfilter: nf_tables: use-after-free in failing rule with bound set Greg Kroah-Hartman
2019-09-08 12:41 ` [PATCH 4.19 15/57] tools: bpftool: fix error message (prog -> object) Greg Kroah-Hartman
2019-09-08 12:41 ` [PATCH 4.19 16/57] hv_netvsc: Fix a warning of suspicious RCU usage Greg Kroah-Hartman
2019-09-08 12:41 ` [PATCH 4.19 17/57] net: tc35815: Explicitly check NET_IP_ALIGN is not zero in tc35815_rx Greg Kroah-Hartman
2019-09-08 12:41 ` [PATCH 4.19 18/57] Bluetooth: btqca: Add a short delay before downloading the NVM Greg Kroah-Hartman
2019-09-08 12:41 ` [PATCH 4.19 19/57] Bluetooth: hidp: Let hidp_send_message return number of queued bytes Greg Kroah-Hartman
2019-09-09 12:15 ` Pavel Machek
2019-09-09 13:00 ` Fabian Henneke
2019-09-09 22:59 ` Greg Kroah-Hartman
2019-09-10 6:27 ` Fabian Henneke
2019-09-10 9:29 ` Greg Kroah-Hartman
2019-09-08 12:41 ` [PATCH 4.19 20/57] ibmveth: Convert multicast list size for little-endian system Greg Kroah-Hartman
2019-09-08 12:41 ` [PATCH 4.19 21/57] gpio: Fix build error of function redefinition Greg Kroah-Hartman
2019-09-09 12:23 ` Pavel Machek
2019-09-08 12:41 ` [PATCH 4.19 22/57] netfilter: nft_flow_offload: skip tcp rst and fin packets Greg Kroah-Hartman
2019-09-08 12:41 ` [PATCH 4.19 23/57] drm/mediatek: use correct device to import PRIME buffers Greg Kroah-Hartman
2019-09-08 12:41 ` [PATCH 4.19 24/57] drm/mediatek: set DMA max segment size Greg Kroah-Hartman
2019-09-08 12:41 ` [PATCH 4.19 25/57] scsi: qla2xxx: Fix gnl.l memory leak on adapter init failure Greg Kroah-Hartman
2019-09-08 12:41 ` [PATCH 4.19 26/57] scsi: target: tcmu: avoid use-after-free after command timeout Greg Kroah-Hartman
2019-09-08 12:41 ` [PATCH 4.19 27/57] cxgb4: fix a memory leak bug Greg Kroah-Hartman
2019-09-09 13:06 ` Pavel Machek
2019-09-08 12:41 ` [PATCH 4.19 28/57] liquidio: add cleanup in octeon_setup_iq() Greg Kroah-Hartman
2019-09-08 12:41 ` [PATCH 4.19 29/57] net: myri10ge: fix memory leaks Greg Kroah-Hartman
2019-09-08 12:41 ` [PATCH 4.19 30/57] lan78xx: Fix " Greg Kroah-Hartman
2019-09-08 12:41 ` [PATCH 4.19 31/57] vfs: fix page locking deadlocks when deduping files Greg Kroah-Hartman
2019-09-08 12:41 ` [PATCH 4.19 32/57] cx82310_eth: fix a memory leak bug Greg Kroah-Hartman
2019-09-08 12:41 ` [PATCH 4.19 33/57] net: kalmia: fix memory leaks Greg Kroah-Hartman
2019-09-08 12:41 ` [PATCH 4.19 34/57] ibmvnic: Unmap DMA address of TX descriptor buffers after use Greg Kroah-Hartman
2019-09-08 12:41 ` [PATCH 4.19 35/57] net: cavium: fix driver name Greg Kroah-Hartman
2019-09-08 12:42 ` [PATCH 4.19 36/57] wimax/i2400m: fix a memory leak bug Greg Kroah-Hartman
2019-09-08 12:42 ` [PATCH 4.19 37/57] ravb: Fix use-after-free ravb_tstamp_skb Greg Kroah-Hartman
2019-09-08 12:42 ` [PATCH 4.19 38/57] kprobes: Fix potential deadlock in kprobe_optimizer() Greg Kroah-Hartman
2019-09-08 12:42 ` [PATCH 4.19 39/57] HID: cp2112: prevent sleeping function called from invalid context Greg Kroah-Hartman
2019-09-08 12:42 ` Greg Kroah-Hartman [this message]
2019-09-08 12:42 ` [PATCH 4.19 41/57] Input: hyperv-keyboard: Use in-place iterator API in the channel callback Greg Kroah-Hartman
2019-09-08 12:42 ` [PATCH 4.19 42/57] Tools: hv: kvp: eliminate may be used uninitialized warning Greg Kroah-Hartman
2019-09-08 12:42 ` [PATCH 4.19 43/57] nvme-multipath: fix possible I/O hang when paths are updated Greg Kroah-Hartman
2019-09-08 12:42 ` [PATCH 4.19 44/57] IB/mlx4: Fix memory leaks Greg Kroah-Hartman
2019-09-08 12:42 ` [PATCH 4.19 45/57] infiniband: hfi1: fix a memory leak bug Greg Kroah-Hartman
2019-09-08 12:42 ` [PATCH 4.19 46/57] infiniband: hfi1: fix memory leaks Greg Kroah-Hartman
2019-09-08 12:42 ` [PATCH 4.19 47/57] selftests: kvm: fix state save/load on processors without XSAVE Greg Kroah-Hartman
2019-09-08 12:42 ` [PATCH 4.19 48/57] selftests/kvm: make platform_info_test pass on AMD Greg Kroah-Hartman
2019-09-08 12:42 ` [PATCH 4.19 49/57] ceph: fix buffer free while holding i_ceph_lock in __ceph_setxattr() Greg Kroah-Hartman
2019-09-08 12:42 ` [PATCH 4.19 50/57] ceph: fix buffer free while holding i_ceph_lock in __ceph_build_xattrs_blob() Greg Kroah-Hartman
2019-09-08 12:42 ` [PATCH 4.19 51/57] ceph: fix buffer free while holding i_ceph_lock in fill_inode() Greg Kroah-Hartman
2019-09-08 12:42 ` [PATCH 4.19 52/57] KVM: arm/arm64: Only skip MMIO insn once Greg Kroah-Hartman
2019-09-08 12:42 ` [PATCH 4.19 53/57] afs: Fix leak in afs_lookup_cell_rcu() Greg Kroah-Hartman
2019-09-08 12:42 ` [PATCH 4.19 54/57] KVM: arm/arm64: VGIC: Properly initialise private IRQ affinity Greg Kroah-Hartman
2019-09-08 12:42 ` [PATCH 4.19 55/57] x86/boot/compressed/64: Fix missing initialization in find_trampoline_placement() Greg Kroah-Hartman
2019-09-08 12:42 ` [PATCH 4.19 56/57] libceph: allow ceph_buffer_put() to receive a NULL ceph_buffer Greg Kroah-Hartman
2019-09-08 12:42 ` [PATCH 4.19 57/57] Revert "x86/apic: Include the LDR when clearing out APIC registers" Greg Kroah-Hartman
2019-09-09 3:12 ` [PATCH 4.19 00/57] 4.19.72-stable review Naresh Kamboju
2019-09-09 19:39 ` Guenter Roeck
2019-09-10 9:20 ` Jon Hunter
2019-09-10 9:27 ` Jack Wang
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