From: Simon Horman <horms@verge.net.au>
To: Thomas Renninger <trenn@suse.de>
Cc: yinghai@kernel.org, kexec@lists.infradead.org,
ebiederm@xmission.com, vgoyal@redhat.com
Subject: Re: [PATCH 3/4] kexec-tools: Fix possible overflows and make use of dbg_memrange() macro
Date: Sun, 26 May 2013 22:16:26 +0900 [thread overview]
Message-ID: <20130526131626.GC11134@verge.net.au> (raw)
In-Reply-To: <1369213056-77661-4-git-send-email-trenn@suse.de>
On Wed, May 22, 2013 at 10:57:35AM +0200, Thomas Renninger wrote:
> add_memmap() will add another memrange, therefore we need an additional
> array entry and need to check for
> if (nr_entries >= CRASH_MAX_MEMMAP_NR - 1)
>
> Same for delete_memmap: If a region has to be split an additional region is
> added first, so we again have to check for:
> if (nr_entries >= CRASH_MAX_MEMMAP_NR - 1)
>
> In add_memmap we know the amount of range entries. No need to check for the
> ugly:
> - if (mstart == 0 && mend == 0)
> - break;
> condition, just let the loop go until nr_entries.
>
> Signed-off-by: Thomas Renninger <trenn@suse.de>
> Signed-off-by: Thomas Renninger <Thomas Renninger" trenn@suse.de>
This patch seems fine, however, the second Signed-off-by line seems to be a
malformed duplicate of the first.
> ---
> kexec/arch/i386/crashdump-x86.c | 35 ++++++++---------------------------
> 1 files changed, 8 insertions(+), 27 deletions(-)
>
> diff --git a/kexec/arch/i386/crashdump-x86.c b/kexec/arch/i386/crashdump-x86.c
> index 9b5a7cd..7fd1c5b 100644
> --- a/kexec/arch/i386/crashdump-x86.c
> +++ b/kexec/arch/i386/crashdump-x86.c
> @@ -545,14 +545,12 @@ static int add_memmap(struct memory_range *memmap_p, unsigned long long addr,
> else
> nr_entries++;
> }
> - if (nr_entries == CRASH_MAX_MEMMAP_NR)
> + if (nr_entries >= CRASH_MAX_MEMMAP_NR - 1)
> return -1;
>
> - for (i = 0; i < CRASH_MAX_MEMMAP_NR; i++) {
> + for (i = 0; i < nr_entries; i++) {
> mstart = memmap_p[i].start;
> mend = memmap_p[i].end;
> - if (mstart == 0 && mend == 0)
> - break;
> if (mstart <= (addr+size-1) && mend >=addr)
> /* Overlapping region. */
> return -1;
> @@ -565,16 +563,8 @@ static int add_memmap(struct memory_range *memmap_p, unsigned long long addr,
> memmap_p[tidx].start = addr;
> memmap_p[tidx].end = addr + size - 1;
>
> - dbgprintf("Memmap after adding segment\n");
> - for (i = 0; i < CRASH_MAX_MEMMAP_NR; i++) {
> - mstart = memmap_p[i].start;
> - mend = memmap_p[i].end;
> - if (mstart == 0 && mend == 0)
> - break;
> - dbgprintf("%016llx - %016llx\n",
> - mstart, mend);
> - }
> -
> + nr_entries++;
> + dbg_memrange("Memmap after adding segment", &memmap_p, nr_entries);
> return 0;
> }
>
> @@ -600,8 +590,7 @@ static int delete_memmap(struct memory_range *memmap_p, unsigned long long addr,
> else
> nr_entries++;
> }
> - if (nr_entries == CRASH_MAX_MEMMAP_NR)
> - /* List if full */
> + if (nr_entries >= CRASH_MAX_MEMMAP_NR - 1)
> return -1;
>
> for (i = 0; i < CRASH_MAX_MEMMAP_NR; i++) {
> @@ -643,25 +632,17 @@ static int delete_memmap(struct memory_range *memmap_p, unsigned long long addr,
> for (j = nr_entries-1; j > tidx; j--)
> memmap_p[j+1] = memmap_p[j];
> memmap_p[tidx+1] = temp_region;
> + nr_entries++;
> }
> if ((operation == -1) && tidx >=0) {
> /* Delete the exact match memory region. */
> for (j = i+1; j < CRASH_MAX_MEMMAP_NR; j++)
> memmap_p[j-1] = memmap_p[j];
> memmap_p[j-1].start = memmap_p[j-1].end = 0;
> + nr_entries--;
> }
>
> - dbgprintf("Memmap after deleting segment\n");
> - for (i = 0; i < CRASH_MAX_MEMMAP_NR; i++) {
> - mstart = memmap_p[i].start;
> - mend = memmap_p[i].end;
> - if (mstart == 0 && mend == 0) {
> - break;
> - }
> - dbgprintf("%016llx - %016llx\n",
> - mstart, mend);
> - }
> -
> + dbg_memrange("Memmap after deleting segment", &memmap_p, nr_entries);
> return 0;
> }
>
> --
> 1.7.6.1
>
>
> _______________________________________________
> kexec mailing list
> kexec@lists.infradead.org
> http://lists.infradead.org/mailman/listinfo/kexec
>
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next prev parent reply other threads:[~2013-05-26 13:16 UTC|newest]
Thread overview: 10+ messages / expand[flat|nested] mbox.gz Atom feed top
2013-05-22 8:57 Different minor kexec cleanups Thomas Renninger
2013-05-22 8:57 ` [PATCH 1/4] kexec-tools: Cleanup: Fix indentation Thomas Renninger
2013-05-26 13:13 ` Simon Horman
2013-05-22 8:57 ` [PATCH 2/4] kexec-tools: Introduce dbg_memrange() macro and make use of it Thomas Renninger
2013-05-26 13:17 ` Simon Horman
2013-05-22 8:57 ` [PATCH 3/4] kexec-tools: Fix possible overflows and make use of dbg_memrange() macro Thomas Renninger
2013-05-26 13:16 ` Simon Horman [this message]
2013-05-22 8:57 ` [PATCH 4/4] kexec-tools: Add cgroup_disable=memory to crash kernel parameters Thomas Renninger
2013-05-26 13:20 ` Simon Horman
2013-05-28 14:48 ` Vivek Goyal
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