| [3c9b86e] | 1 | Submitted By: Jim Gifford <jim@linuxfromscratch.org> |
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| 2 | Date: 07-14-2006 |
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| 3 | Initial Package Version: 0.97 |
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| 4 | Upstream Status: Unknown |
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| 5 | Origin: Grub Bug Report - http://savannah.gnu.org/bugs/?func=detailitem&item_id=11312 |
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| 6 | Description: This patch fixes the following issues on x86_64 |
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| 7 | 1) malloc'd pages seem to lack the execute bit on x86_64; |
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| 8 | 2) grub seems to use some stack pointer diversion to malloc'd pages; |
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| 9 | 3) nested functions execute data on the stack; |
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| 10 | 4) this causes a segfault (at least on my machine) |
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| 11 | |
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| 12 | diff -Naur grub-0.97.orig/grub/asmstub.c grub-0.97/grub/asmstub.c |
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| 13 | --- grub-0.97.orig/grub/asmstub.c 2005-02-16 12:45:14.000000000 -0800 |
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| 14 | +++ grub-0.97/grub/asmstub.c 2006-07-14 12:38:08.305902933 -0700 |
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| 15 | @@ -43,6 +43,8 @@ |
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| 16 | #include <termios.h> |
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| 17 | #include <signal.h> |
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| 18 | |
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| 19 | +#include <sys/mman.h> |
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| 20 | + |
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| 21 | #ifdef __linux__ |
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| 22 | # include <sys/ioctl.h> /* ioctl */ |
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| 23 | # if !defined(__GLIBC__) || \ |
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| 24 | @@ -142,14 +144,25 @@ |
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| 25 | } |
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| 26 | |
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| 27 | assert (grub_scratch_mem == 0); |
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| 28 | - scratch = malloc (0x100000 + EXTENDED_MEMSIZE + 15); |
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| 29 | + scratch = mmap(NULL, |
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| 30 | + 0x100000 + EXTENDED_MEMSIZE + 15, |
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| 31 | + PROT_EXEC | PROT_READ | PROT_WRITE, |
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| 32 | + MAP_PRIVATE | MAP_GROWSDOWN | MAP_ANONYMOUS | MAP_32BIT, |
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| 33 | + -1, |
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| 34 | + 0); |
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| 35 | + |
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| 36 | assert (scratch); |
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| 37 | grub_scratch_mem = (char *) ((((int) scratch) >> 4) << 4); |
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| 38 | |
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| 39 | /* FIXME: simulate the memory holes using mprot, if available. */ |
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| 40 | |
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| 41 | assert (disks == 0); |
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| 42 | - disks = malloc (NUM_DISKS * sizeof (*disks)); |
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| 43 | + disks = mmap(NULL, |
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| 44 | + NUM_DISKS * sizeof (*disks), |
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| 45 | + PROT_EXEC | PROT_READ | PROT_WRITE, |
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| 46 | + MAP_PRIVATE | MAP_GROWSDOWN | MAP_ANONYMOUS | MAP_32BIT, |
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| 47 | + -1, |
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| 48 | + 0); |
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| 49 | assert (disks); |
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| 50 | /* Initialize DISKS. */ |
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| 51 | for (i = 0; i < NUM_DISKS; i++) |
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| 52 | @@ -215,9 +228,9 @@ |
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| 53 | /* Release memory. */ |
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| 54 | restore_device_map (device_map); |
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| 55 | device_map = 0; |
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| 56 | - free (disks); |
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| 57 | + munmap(disks, NUM_DISKS * sizeof (*disks)); |
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| 58 | disks = 0; |
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| 59 | - free (scratch); |
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| 60 | + munmap(scratch, 0x100000 + EXTENDED_MEMSIZE + 15); |
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| 61 | grub_scratch_mem = 0; |
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| 62 | |
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| 63 | if (serial_device) |
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