kernel/kexec_file.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-)
In some case initrd can be large. For example, it could be a netboot
image loaded by u-root, that is kexec'ing into it.
The maximum size of initrd is arbitrary set to 2G. Also, the limit is
not very obvious because it is hidden behind a generic INT_MAX macro.
Theoretically, we could make it LONG_MAX, but it is safer to keep it
sane, and just increase it to 4G.
Increase the size to 4G, and make it obvious by having a new macro
that specifies the maximum file size supported by kexec_file_load()
syscall: KEXEC_FILE_SIZE_MAX.
Signed-off-by: Pasha Tatashin <tatashin@google.com>
---
kernel/kexec_file.c | 8 ++++++--
1 file changed, 6 insertions(+), 2 deletions(-)
diff --git a/kernel/kexec_file.c b/kernel/kexec_file.c
index 8347fc158d2b..1be2227b33e6 100644
--- a/kernel/kexec_file.c
+++ b/kernel/kexec_file.c
@@ -31,6 +31,9 @@
static int kexec_calculate_store_digests(struct kimage *image);
+/* Maximum size in bytes for kernel/initrd files. */
+#define KEXEC_FILE_SIZE_MAX (4UL << 30)
+
/*
* Currently this is the only default function that is exported as some
* architectures need it to do additional handlings.
@@ -227,7 +230,8 @@ kimage_file_prepare_segments(struct kimage *image, int kernel_fd, int initrd_fd,
void *ldata;
ret = kernel_read_file_from_fd(kernel_fd, 0, &image->kernel_buf,
- INT_MAX, NULL, READING_KEXEC_IMAGE);
+ KEXEC_FILE_SIZE_MAX, NULL,
+ READING_KEXEC_IMAGE);
if (ret < 0)
return ret;
image->kernel_buf_len = ret;
@@ -247,7 +251,7 @@ kimage_file_prepare_segments(struct kimage *image, int kernel_fd, int initrd_fd,
/* It is possible that there no initramfs is being loaded */
if (!(flags & KEXEC_FILE_NO_INITRAMFS)) {
ret = kernel_read_file_from_fd(initrd_fd, 0, &image->initrd_buf,
- INT_MAX, NULL,
+ KEXEC_FILE_SIZE_MAX, NULL,
READING_KEXEC_INITRAMFS);
if (ret < 0)
goto out;
--
2.36.1.124.g0e6072fb45-googOn Thu, May 26, 2022 at 4:38 PM Pasha Tatashin
<pasha.tatashin@soleen.com> wrote:
>
> In some case initrd can be large. For example, it could be a netboot
> image loaded by u-root, that is kexec'ing into it.
>
> The maximum size of initrd is arbitrary set to 2G. Also, the limit is
> not very obvious because it is hidden behind a generic INT_MAX macro.
>
> Theoretically, we could make it LONG_MAX, but it is safer to keep it
> sane, and just increase it to 4G.
>
> Increase the size to 4G, and make it obvious by having a new macro
> that specifies the maximum file size supported by kexec_file_load()
> syscall: KEXEC_FILE_SIZE_MAX.
>
> Signed-off-by: Pasha Tatashin <tatashin@google.com>
Should be instead:
Signed-off-by: Pasha Tatashin <pasha.tatashin@soleen.com>
Thanks,
Pasha
> ---
> kernel/kexec_file.c | 8 ++++++--
> 1 file changed, 6 insertions(+), 2 deletions(-)
>
> diff --git a/kernel/kexec_file.c b/kernel/kexec_file.c
> index 8347fc158d2b..1be2227b33e6 100644
> --- a/kernel/kexec_file.c
> +++ b/kernel/kexec_file.c
> @@ -31,6 +31,9 @@
>
> static int kexec_calculate_store_digests(struct kimage *image);
>
> +/* Maximum size in bytes for kernel/initrd files. */
> +#define KEXEC_FILE_SIZE_MAX (4UL << 30)
> +
> /*
> * Currently this is the only default function that is exported as some
> * architectures need it to do additional handlings.
> @@ -227,7 +230,8 @@ kimage_file_prepare_segments(struct kimage *image, int kernel_fd, int initrd_fd,
> void *ldata;
>
> ret = kernel_read_file_from_fd(kernel_fd, 0, &image->kernel_buf,
> - INT_MAX, NULL, READING_KEXEC_IMAGE);
> + KEXEC_FILE_SIZE_MAX, NULL,
> + READING_KEXEC_IMAGE);
> if (ret < 0)
> return ret;
> image->kernel_buf_len = ret;
> @@ -247,7 +251,7 @@ kimage_file_prepare_segments(struct kimage *image, int kernel_fd, int initrd_fd,
> /* It is possible that there no initramfs is being loaded */
> if (!(flags & KEXEC_FILE_NO_INITRAMFS)) {
> ret = kernel_read_file_from_fd(initrd_fd, 0, &image->initrd_buf,
> - INT_MAX, NULL,
> + KEXEC_FILE_SIZE_MAX, NULL,
> READING_KEXEC_INITRAMFS);
> if (ret < 0)
> goto out;
> --
> 2.36.1.124.g0e6072fb45-goog
>
On Thu, May 26, 2022 at 4:45 PM Pasha Tatashin <pasha.tatashin@soleen.com> wrote: > > On Thu, May 26, 2022 at 4:38 PM Pasha Tatashin > <pasha.tatashin@soleen.com> wrote: > > > > In some case initrd can be large. For example, it could be a netboot > > image loaded by u-root, that is kexec'ing into it. > > > > The maximum size of initrd is arbitrary set to 2G. Also, the limit is > > not very obvious because it is hidden behind a generic INT_MAX macro. > > > > Theoretically, we could make it LONG_MAX, but it is safer to keep it > > sane, and just increase it to 4G. > > > > Increase the size to 4G, and make it obvious by having a new macro > > that specifies the maximum file size supported by kexec_file_load() > > syscall: KEXEC_FILE_SIZE_MAX. It appears that since: f7a4f689bca6072492626938aad6dd2f32c5bf97 fs/kernel_read_file: Remove redundant size argument Introduced a change to kernel_read_file to limit the maximum file internally from SIZE_MAX to INT_MAX. Therefore, more changes will be needed. I will work on them and sent them in v2. > > > > Signed-off-by: Pasha Tatashin <tatashin@google.com> > > Should be instead: > Signed-off-by: Pasha Tatashin <pasha.tatashin@soleen.com> > > Thanks, > Pasha > > > --- > > kernel/kexec_file.c | 8 ++++++-- > > 1 file changed, 6 insertions(+), 2 deletions(-) > > > > diff --git a/kernel/kexec_file.c b/kernel/kexec_file.c > > index 8347fc158d2b..1be2227b33e6 100644 > > --- a/kernel/kexec_file.c > > +++ b/kernel/kexec_file.c > > @@ -31,6 +31,9 @@ > > > > static int kexec_calculate_store_digests(struct kimage *image); > > > > +/* Maximum size in bytes for kernel/initrd files. */ > > +#define KEXEC_FILE_SIZE_MAX (4UL << 30) Also, I will address 32-bit, with picking minimum between SIZE_MAX and kexec max file. Thanks, Pasha
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