vbatts/grub
1
0
Fork 0
Code Issues Pull requests Releases Wiki Activity

Avoid using Reed-Solomon with 0 redundancy.

Browse source 
* grub-core/kern/i386/pc/startup.S: Remove 0-data check.
	* grub-core/lib/reed_solomon.c (decode_block): Do not proceed on 0 data
	or 0 redundancy.
	(grub_reed_solomon_add_redundancy): Do not proceed with 0 redundancy.
	(grub_reed_solomon_recover): Likewise.
This commit is contained in:
Vladimir 'phcoder' Serbinenko 2010-12-27 07:09:43 +01:00
parent 25dd47804d
commit c76386454e
3 changed files with 24 additions and 4 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

10
ChangeLog
View file

@ -1,3 +1,13 @@
2010-12-27 Vladimir Serbinenko <phcoder@gmail.com>
Avoid using Reed-Solomon with 0 redundancy.
* grub-core/kern/i386/pc/startup.S: Remove 0-data check.
* grub-core/lib/reed_solomon.c (decode_block): Do not proceed on 0 data
or 0 redundancy.
(grub_reed_solomon_add_redundancy): Do not proceed with 0 redundancy.
(grub_reed_solomon_recover): Likewise.
2010-12-27 Vladimir Serbinenko <phcoder@gmail.com> 2010-12-27 Vladimir Serbinenko <phcoder@gmail.com>
Don't use disk subsystem in freebsd_boot. Don't use disk subsystem in freebsd_boot.

2
grub-core/kern/i386/pc/startup.S
View file

@ -151,8 +151,6 @@ LOCAL (codestart):
addl $(GRUB_KERNEL_MACHINE_RAW_SIZE - GRUB_KERNEL_I386_PC_NO_REED_SOLOMON_PART), %edx addl $(GRUB_KERNEL_MACHINE_RAW_SIZE - GRUB_KERNEL_I386_PC_NO_REED_SOLOMON_PART), %edx
movl reed_solomon_redundancy, %ecx movl reed_solomon_redundancy, %ecx
leal _start + GRUB_KERNEL_I386_PC_NO_REED_SOLOMON_PART, %eax leal _start + GRUB_KERNEL_I386_PC_NO_REED_SOLOMON_PART, %eax
testl %edx, %edx
jz post_reed_solomon
call EXT_C (grub_reed_solomon_recover) call EXT_C (grub_reed_solomon_recover)
jmp post_reed_solomon jmp post_reed_solomon

16
grub-core/lib/reed_solomon.c
View file

@ -372,6 +372,10 @@ decode_block (gf_single_t *ptr, grub_size_t s,
grub_size_t rr = (rs + SECTOR_SIZE - 1 - i) / SECTOR_SIZE; grub_size_t rr = (rs + SECTOR_SIZE - 1 - i) / SECTOR_SIZE;
gf_single_t m[ds + rr]; gf_single_t m[ds + rr];
/* Nothing to do. */
if (!ds || !rr)
continue;
for (j = 0; j < (int) ds; j++) for (j = 0; j < (int) ds; j++)
m[j] = ptr[SECTOR_SIZE * j + i]; m[j] = ptr[SECTOR_SIZE * j + i];
for (j = 0; j < (int) rr; j++) for (j = 0; j < (int) rr; j++)
@ -414,6 +418,10 @@ grub_reed_solomon_add_redundancy (void *buffer, grub_size_t data_size,
gf_single_t *ptr = buffer; gf_single_t *ptr = buffer;
gf_single_t *rptr = ptr + s; gf_single_t *rptr = ptr + s;
/* Nothing to do. */
if (!rs)
return;
while (s > 0) while (s > 0)
{ {
grub_size_t tt; grub_size_t tt;
@ -441,6 +449,10 @@ grub_reed_solomon_recover (void *ptr_, grub_size_t s, grub_size_t rs)
gf_single_t *ptr = ptr_; gf_single_t *ptr = ptr_;
gf_single_t *rptr = ptr + s; gf_single_t *rptr = ptr + s;
/* Nothing to do. */
if (!rs)
return;
#if defined (STANDALONE) #if defined (STANDALONE)
init_inverts (); init_inverts ();
#endif #endif
@ -454,8 +466,8 @@ grub_reed_solomon_recover (void *ptr_, grub_size_t s, grub_size_t rs)
tt = cs + crs; tt = cs + crs;
if (tt > MAX_BLOCK_SIZE) if (tt > MAX_BLOCK_SIZE)
{ {
cs = cs * MAX_BLOCK_SIZE / tt; cs = (cs * MAX_BLOCK_SIZE) / tt;
crs = crs * MAX_BLOCK_SIZE / tt; crs = (crs * MAX_BLOCK_SIZE) / tt;
} }
decode_block (ptr, cs, rptr, crs); decode_block (ptr, cs, rptr, crs);
ptr += cs; ptr += cs;