From: Sasha Levin <sashal@kernel.org>
To: linux-kernel@vger.kernel.org, stable@vger.kernel.org
Cc: Arvind Sankar <nivedita@alum.mit.edu>,
Ard Biesheuvel <ardb@kernel.org>, Ingo Molnar <mingo@kernel.org>,
Sasha Levin <sashal@kernel.org>
Subject: [PATCH AUTOSEL 4.14 12/22] x86/boot: Use unsigned comparison for addresses
Date: Thu, 9 Apr 2020 23:50:34 -0400 [thread overview]
Message-ID: <20200410035044.9698-12-sashal@kernel.org> (raw)
In-Reply-To: <20200410035044.9698-1-sashal@kernel.org>
From: Arvind Sankar <nivedita@alum.mit.edu>
[ Upstream commit 81a34892c2c7c809f9c4e22c5ac936ae673fb9a2 ]
The load address is compared with LOAD_PHYSICAL_ADDR using a signed
comparison currently (using jge instruction).
When loading a 64-bit kernel using the new efi32_pe_entry() point added by:
97aa276579b2 ("efi/x86: Add true mixed mode entry point into .compat section")
using Qemu with -m 3072, the firmware actually loads us above 2Gb,
resulting in a very early crash.
Use the JAE instruction to perform a unsigned comparison instead, as physical
addresses should be considered unsigned.
Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lore.kernel.org/r/20200301230436.2246909-6-nivedita@alum.mit.edu
Link: https://lore.kernel.org/r/20200308080859.21568-14-ardb@kernel.org
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
arch/x86/boot/compressed/head_32.S | 2 +-
arch/x86/boot/compressed/head_64.S | 4 ++--
2 files changed, 3 insertions(+), 3 deletions(-)
diff --git a/arch/x86/boot/compressed/head_32.S b/arch/x86/boot/compressed/head_32.S
index 37380c0d59996..01d628ea34024 100644
--- a/arch/x86/boot/compressed/head_32.S
+++ b/arch/x86/boot/compressed/head_32.S
@@ -106,7 +106,7 @@ ENTRY(startup_32)
notl %eax
andl %eax, %ebx
cmpl $LOAD_PHYSICAL_ADDR, %ebx
- jge 1f
+ jae 1f
#endif
movl $LOAD_PHYSICAL_ADDR, %ebx
1:
diff --git a/arch/x86/boot/compressed/head_64.S b/arch/x86/boot/compressed/head_64.S
index 39fdede523f21..a25127916e679 100644
--- a/arch/x86/boot/compressed/head_64.S
+++ b/arch/x86/boot/compressed/head_64.S
@@ -105,7 +105,7 @@ ENTRY(startup_32)
notl %eax
andl %eax, %ebx
cmpl $LOAD_PHYSICAL_ADDR, %ebx
- jge 1f
+ jae 1f
#endif
movl $LOAD_PHYSICAL_ADDR, %ebx
1:
@@ -280,7 +280,7 @@ ENTRY(startup_64)
notq %rax
andq %rax, %rbp
cmpq $LOAD_PHYSICAL_ADDR, %rbp
- jge 1f
+ jae 1f
#endif
movq $LOAD_PHYSICAL_ADDR, %rbp
1:
--
2.20.1
next prev parent reply other threads:[~2020-04-10 3:51 UTC|newest]
Thread overview: 22+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-04-10 3:50 [PATCH AUTOSEL 4.14 01/22] null_blk: Fix the null_add_dev() error path Sasha Levin
2020-04-10 3:50 ` [PATCH AUTOSEL 4.14 02/22] null_blk: Handle null_add_dev() failures properly Sasha Levin
2020-04-10 3:50 ` [PATCH AUTOSEL 4.14 03/22] null_blk: fix spurious IO errors after failed past-wp access Sasha Levin
2020-04-10 3:50 ` [PATCH AUTOSEL 4.14 04/22] x86: Don't let pgprot_modify() change the page encryption bit Sasha Levin
2020-04-10 3:50 ` [PATCH AUTOSEL 4.14 05/22] block: keep bdi->io_pages in sync with max_sectors_kb for stacked devices Sasha Levin
2020-04-10 3:50 ` [PATCH AUTOSEL 4.14 06/22] irqchip/versatile-fpga: Handle chained IRQs properly Sasha Levin
2020-04-10 3:50 ` [PATCH AUTOSEL 4.14 07/22] sched: Avoid scale real weight down to zero Sasha Levin
2020-04-10 3:50 ` [PATCH AUTOSEL 4.14 08/22] selftests/x86/ptrace_syscall_32: Fix no-vDSO segfault Sasha Levin
2020-04-10 3:50 ` [PATCH AUTOSEL 4.14 09/22] PCI/switchtec: Fix init_completion race condition with poll_wait() Sasha Levin
2020-04-10 3:50 ` [PATCH AUTOSEL 4.14 10/22] libata: Remove extra scsi_host_put() in ata_scsi_add_hosts() Sasha Levin
2020-04-10 3:50 ` [PATCH AUTOSEL 4.14 11/22] gfs2: Don't demote a glock until its revokes are written Sasha Levin
2020-04-10 3:50 ` Sasha Levin [this message]
2020-04-10 3:50 ` [PATCH AUTOSEL 4.14 13/22] efi/x86: Ignore the memory attributes table on i386 Sasha Levin
2020-04-10 3:50 ` [PATCH AUTOSEL 4.14 14/22] genirq/irqdomain: Check pointer in irq_domain_alloc_irqs_hierarchy() Sasha Levin
2020-04-10 3:50 ` [PATCH AUTOSEL 4.14 15/22] block: Fix use-after-free issue accessing struct io_cq Sasha Levin
2020-04-10 3:50 ` [PATCH AUTOSEL 4.14 16/22] usb: dwc3: core: add support for disabling SS instances in park mode Sasha Levin
2020-04-10 3:50 ` [PATCH AUTOSEL 4.14 17/22] irqchip/gic-v4: Provide irq_retrigger to avoid circular locking dependency Sasha Levin
2020-04-10 3:50 ` [PATCH AUTOSEL 4.14 18/22] locking/lockdep: Avoid recursion in lockdep_count_{for,back}ward_deps() Sasha Levin
2020-04-10 3:50 ` [PATCH AUTOSEL 4.14 19/22] block, bfq: fix use-after-free in bfq_idle_slice_timer_body Sasha Levin
2020-04-10 3:50 ` [PATCH AUTOSEL 4.14 20/22] btrfs: hold a ref on the root in btrfs_recover_relocation Sasha Levin
2020-04-10 3:50 ` [PATCH AUTOSEL 4.14 21/22] btrfs: remove a BUG_ON() from merge_reloc_roots() Sasha Levin
2020-04-10 3:50 ` [PATCH AUTOSEL 4.14 22/22] btrfs: track reloc roots based on their commit root bytenr Sasha Levin
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