lkml.org 
[lkml]   [2012]   [Dec]   [13]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH v6 10/27] x86, boot: move checking of cmd_line_ptr out of common path
Date
cmdline.c::__cmdline_find_option... are shared between
16-bit setup code and 32/64 bit decompressor code.

for 32/64 only path via kexec, we should not check if ptr less 1M.
as those cmdline could be put above 1M, or even 4G.

Move out accessible checking out of __cmdline_find_option()
So decompressor in misc.c can parse cmdline correctly.

Signed-off-by: Yinghai Lu <yinghai@kernel.org>
---
arch/x86/boot/boot.h | 14 ++++++++++++--
arch/x86/boot/cmdline.c | 8 ++++----
2 files changed, 16 insertions(+), 6 deletions(-)

diff --git a/arch/x86/boot/boot.h b/arch/x86/boot/boot.h
index 18997e5..7fadf80 100644
--- a/arch/x86/boot/boot.h
+++ b/arch/x86/boot/boot.h
@@ -289,12 +289,22 @@ int __cmdline_find_option(u32 cmdline_ptr, const char *option, char *buffer, int
int __cmdline_find_option_bool(u32 cmdline_ptr, const char *option);
static inline int cmdline_find_option(const char *option, char *buffer, int bufsize)
{
- return __cmdline_find_option(boot_params.hdr.cmd_line_ptr, option, buffer, bufsize);
+ u32 cmd_line_ptr = boot_params.hdr.cmd_line_ptr;
+
+ if (cmd_line_ptr >= 0x100000)
+ return -1; /* inaccessible */
+
+ return __cmdline_find_option(cmd_line_ptr, option, buffer, bufsize);
}

static inline int cmdline_find_option_bool(const char *option)
{
- return __cmdline_find_option_bool(boot_params.hdr.cmd_line_ptr, option);
+ u32 cmd_line_ptr = boot_params.hdr.cmd_line_ptr;
+
+ if (cmd_line_ptr >= 0x100000)
+ return -1; /* inaccessible */
+
+ return __cmdline_find_option_bool(cmd_line_ptr, option);
}


diff --git a/arch/x86/boot/cmdline.c b/arch/x86/boot/cmdline.c
index 6b3b6f7..768f00f 100644
--- a/arch/x86/boot/cmdline.c
+++ b/arch/x86/boot/cmdline.c
@@ -41,8 +41,8 @@ int __cmdline_find_option(u32 cmdline_ptr, const char *option, char *buffer, int
st_bufcpy /* Copying this to buffer */
} state = st_wordstart;

- if (!cmdline_ptr || cmdline_ptr >= 0x100000)
- return -1; /* No command line, or inaccessible */
+ if (!cmdline_ptr)
+ return -1; /* No command line */

cptr = cmdline_ptr & 0xf;
set_fs(cmdline_ptr >> 4);
@@ -111,8 +111,8 @@ int __cmdline_find_option_bool(u32 cmdline_ptr, const char *option)
st_wordskip, /* Miscompare, skip */
} state = st_wordstart;

- if (!cmdline_ptr || cmdline_ptr >= 0x100000)
- return -1; /* No command line, or inaccessible */
+ if (!cmdline_ptr)
+ return -1; /* No command line */

cptr = cmdline_ptr & 0xf;
set_fs(cmdline_ptr >> 4);
--
1.7.10.4


\
 
 \ /
  Last update: 2012-12-14 00:41    [W:0.314 / U:0.024 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site