On 04/02/2013 05:43 PM, Suzuki K. Poulose wrote:
> Zhang,
>
> Sorry, it was my mistake. I have updated my patch based on the upstream
> tree now.
>
> ---
>
> From: Suzuki K. Poulose <suzuki at in.ibm.com>
>
> Enforce size check for kernel command line to make sure it
> doesn't overflow COMMAND_LINE_SIZE.
>
> Reported-by: Nathan D. Miller <nathanm2 at us.ibm.com>
> Signed-off-by: Suzuki K. Poulose <suzuki at in.ibm.com>
Simon,
Could you please apply this one ?
Thanks
Suzuki
> ---
> kexec/arch/ppc/kexec-elf-ppc.c | 29 ++++++++++++++++-------------
> kexec/arch/ppc/kexec-uImage-ppc.c | 23 ++++++++++++++---------
> 2 files changed, 30 insertions(+), 22 deletions(-)
>
> diff --git a/kexec/arch/ppc/kexec-elf-ppc.c b/kexec/arch/ppc/kexec-elf-ppc.c
> index 3daca2d..98cae9c 100644
> --- a/kexec/arch/ppc/kexec-elf-ppc.c
> +++ b/kexec/arch/ppc/kexec-elf-ppc.c
> @@ -157,7 +157,7 @@ int elf_ppc_load(int argc, char **argv, const char *buf, off_t len,
> struct mem_ehdr ehdr;
> char *command_line, *crash_cmdline, *cmdline_buf;
> char *tmp_cmdline;
> - int command_line_len;
> + int command_line_len, crash_cmdline_len;
> char *dtb;
> int result;
> char *error_msg;
> @@ -244,19 +244,10 @@ int elf_ppc_load(int argc, char **argv, const char *buf, off_t len,
> } else {
> command_line = get_command_line();
> }
> - command_line_len = strlen(command_line) + 1;
> + command_line_len = strlen(command_line);
>
> fixup_nodes[cur_fixup] = NULL;
>
> - /* Need to append some command line parameters internally in case of
> - * taking crash dumps.
> - */
> - if (info->kexec_flags & KEXEC_ON_CRASH) {
> - crash_cmdline = xmalloc(COMMAND_LINE_SIZE);
> - memset((void *)crash_cmdline, 0, COMMAND_LINE_SIZE);
> - } else
> - crash_cmdline = NULL;
> -
> /* Parse the Elf file */
> result = build_elf_exec_info(buf, len, &ehdr, 0);
> if (result < 0) {
> @@ -292,16 +283,23 @@ int elf_ppc_load(int argc, char **argv, const char *buf, off_t len,
> goto out;
> }
>
> - /* If panic kernel is being loaded, additional segments need
> - * to be created.
> + /*
> + * Need to append some command line parameters internally in case of
> + * taking crash dumps. Additional segments need to be created.
> */
> if (info->kexec_flags & KEXEC_ON_CRASH) {
> + crash_cmdline = xmalloc(COMMAND_LINE_SIZE);
> + memset((void *)crash_cmdline, 0, COMMAND_LINE_SIZE);
> result = load_crashdump_segments(info, crash_cmdline,
> max_addr, 0);
> if (result < 0) {
> result = -1;
> goto out;
> }
> + crash_cmdline_len = strlen(crash_cmdline);
> + } else {
> + crash_cmdline = NULL;
> + crash_cmdline_len = 0;
> }
>
> /*
> @@ -337,6 +335,11 @@ int elf_ppc_load(int argc, char **argv, const char *buf, off_t len,
>
> info->entry = (void *)arg_base;
> #else
> + if (crash_cmdline_len + command_line_len + 1 > COMMAND_LINE_SIZE) {
> + printf("Kernel command line exceeds size\n");
> + return -1;
> + }
> +
> cmdline_buf = xmalloc(COMMAND_LINE_SIZE);
> memset((void *)cmdline_buf, 0, COMMAND_LINE_SIZE);
> if (command_line)
> diff --git a/kexec/arch/ppc/kexec-uImage-ppc.c b/kexec/arch/ppc/kexec-uImage-ppc.c
> index 9113fbe..008463b 100644
> --- a/kexec/arch/ppc/kexec-uImage-ppc.c
> +++ b/kexec/arch/ppc/kexec-uImage-ppc.c
> @@ -82,7 +82,7 @@ static int ppc_load_bare_bits(int argc, char **argv, const char *buf,
> {
> char *command_line, *cmdline_buf, *crash_cmdline;
> char *tmp_cmdline;
> - int command_line_len;
> + int command_line_len, crash_cmdline_len;
> char *dtb;
> unsigned int addr;
> unsigned long dtb_addr;
> @@ -178,29 +178,34 @@ static int ppc_load_bare_bits(int argc, char **argv, const char *buf,
>
> add_segment(info, buf, len, load_addr, len + _1MiB);
>
> +
> if (info->kexec_flags & KEXEC_ON_CRASH) {
> crash_cmdline = xmalloc(COMMAND_LINE_SIZE);
> memset((void *)crash_cmdline, 0, COMMAND_LINE_SIZE);
> - } else
> - crash_cmdline = NULL;
> -
> - if (info->kexec_flags & KEXEC_ON_CRASH) {
> ret = load_crashdump_segments(info, crash_cmdline,
> max_addr, 0);
> if (ret < 0) {
> ret = -1;
> goto out;
> }
> + crash_cmdline_len = strlen(crash_cmdline);
> + } else {
> + crash_cmdline = NULL;
> + crash_cmdline_len = 0;
> + }
> +
> + if (crash_cmdline_len + command_line_len + 1 > COMMAND_LINE_SIZE) {
> + printf("Kernel command line exceeds maximum possible length\n");
> + return -1;
> }
>
> cmdline_buf = xmalloc(COMMAND_LINE_SIZE);
> memset((void *)cmdline_buf, 0, COMMAND_LINE_SIZE);
> +
> if (command_line)
> - strncat(cmdline_buf, command_line, command_line_len);
> + strcpy(cmdline_buf, command_line);
> if (crash_cmdline)
> - strncat(cmdline_buf, crash_cmdline,
> - sizeof(crash_cmdline) -
> - strlen(crash_cmdline) - 1);
> + strncat(cmdline_buf, crash_cmdline, crash_cmdline_len);
>
> elf_rel_build_load(info, &info->rhdr, (const char *)purgatory,
> purgatory_size, 0, -1, -1, 0);
>
>
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