> Date: Wed, 24 Apr 2019 22:32:29 +0200
> From: Christian Weisgerber <na...@mips.inka.de>
>
> If you boot efiboot via PXE and at the prompt enter a different boot
> device, e.g.
>
> boot> boot sd0a:/bsd
>
> then efiboot will pretend to honor this
>
> booting sd0a:/bsd: ...
>
> but in fact ignore the device and boot from TFTP instead.
>
>
> In the MI part of the boot loader, open() calls devopen(), which
> picks the right device from the MD devsw[] table in conf.c. open()
> will then try the xxx_open() routines from the file_system[] table
> until one succeeds. This assumes that devices and filesystems are
> entirely orthogonal, which is a bit iffy since the TFTP and disk
> code are independent. tftp_open() succeeds "on" a disk device that
> it never looks at, resulting in the bug above.
>
> The patch below
> (1) adds a check to tftp_open() that we are actually opening a TFTP
> device;
> (2) clears the bootmac variable in devopen() for non-TFTP devices,
> to prevent the kernel from going into netboot mode. (Woe, where
> is my root NFS?)
>
> Tested with arm64 BOOTAA64.EFI and amd64 BOOTX64.EFI.
> The arm64 code can be copied verbatim to armv7. Not done below,
> and not tested for lack of hardware.
>
> amd64/i386 pxeboot already solves this problem with a slightly
> different approach. It has an MD version of open() that allows
> devopen() to directly set the specific file_system[] entry to be
> used. We could pull this modification to open() into the MI code,
> but the contortions in devopen() won't get any prettier.
>
>
> Opinions?
> OKs (including dup'ing the arm64 code to armv7)?
My mind always parses
if (strcmp(a, b))
to have the opposite meaning. Please consider changing this into
if (strcmp(a, b) != 0)
Please do commit the arm64 change to armv7 as well.
> Index: sys/arch/arm64/stand/efiboot/efiboot.c
> ===================================================================
> RCS file: /cvs/src/sys/arch/arm64/stand/efiboot/efiboot.c,v
> retrieving revision 1.22
> diff -u -p -r1.22 efiboot.c
> --- sys/arch/arm64/stand/efiboot/efiboot.c 31 Jan 2019 14:35:06 -0000
> 1.22
> +++ sys/arch/arm64/stand/efiboot/efiboot.c 24 Apr 2019 15:35:51 -0000
> @@ -749,6 +749,14 @@ devopen(struct open_file *f, const char
> dp = &devsw[dev];
> f->f_dev = dp;
>
> + if (strcmp("tftp", dp->dv_name)) {
> + /*
> + * Clear bootmac, to signal that we loaded this file from a
> + * non-network device.
> + */
> + bootmac = NULL;
> + }
> +
> return (*dp->dv_open)(f, unit, part);
> }
>
> Index: sys/arch/arm64/stand/efiboot/efipxe.c
> ===================================================================
> RCS file: /cvs/src/sys/arch/arm64/stand/efiboot/efipxe.c,v
> retrieving revision 1.4
> diff -u -p -r1.4 efipxe.c
> --- sys/arch/arm64/stand/efiboot/efipxe.c 31 Mar 2018 17:43:53 -0000
> 1.4
> +++ sys/arch/arm64/stand/efiboot/efipxe.c 24 Apr 2019 15:00:39 -0000
> @@ -157,6 +157,9 @@ mtftp_open(char *path, struct open_file
> EFI_STATUS status;
> UINT64 size;
>
> + if (strcmp("tftp", f->f_dev->dv_name))
> + return ENXIO;
> +
> if (PXE == NULL)
> return ENXIO;
>
> @@ -295,6 +298,9 @@ mtftp_readdir(struct open_file *f, char
> int
> efitftp_open(char *path, struct open_file *f)
> {
> + if (strcmp("tftp", f->f_dev->dv_name))
> + return ENXIO;
> +
> if (NET == NULL || PXE == NULL)
> return ENXIO;
>
> Index: sys/arch/amd64/stand/efiboot/efipxe.c
> ===================================================================
> RCS file: /cvs/src/sys/arch/amd64/stand/efiboot/efipxe.c,v
> retrieving revision 1.3
> diff -u -p -r1.3 efipxe.c
> --- sys/arch/amd64/stand/efiboot/efipxe.c 30 Jan 2018 20:19:06 -0000
> 1.3
> +++ sys/arch/amd64/stand/efiboot/efipxe.c 24 Apr 2019 19:33:06 -0000
> @@ -127,6 +127,9 @@ tftp_open(char *path, struct open_file *
> EFI_STATUS status;
> UINT64 size;
>
> + if (strcmp("TFTP", f->f_dev->dv_name))
> + return ENXIO;
> +
> if (PXE == NULL)
> return ENXIO;
>
> Index: sys/arch/amd64/stand/libsa/dev_i386.c
> ===================================================================
> RCS file: /cvs/src/sys/arch/amd64/stand/libsa/dev_i386.c,v
> retrieving revision 1.21
> diff -u -p -r1.21 dev_i386.c
> --- sys/arch/amd64/stand/libsa/dev_i386.c 25 Nov 2017 19:02:07 -0000
> 1.21
> +++ sys/arch/amd64/stand/libsa/dev_i386.c 24 Apr 2019 19:40:47 -0000
> @@ -78,6 +78,16 @@ devopen(struct open_file *f, const char
> #endif
> if ((rc = (*dp->dv_open)(f, file)) == 0) {
> f->f_dev = dp;
> +#ifdef EFIBOOT
> + if (strcmp("TFTP", dp->dv_name)) {
> + /*
> + * Clear bootmac, to signal that we loaded
> + * this file from a non-network device.
> + */
> + extern char *bootmac;
> + bootmac = NULL;
> + }
> +#endif
> return 0;
> }
> #ifdef DEBUG
> --
> Christian "naddy" Weisgerber na...@mips.inka.de
>
>
