mtd: fix resetbc on nand w/ min I/O size > 2048

Fix a bug in linksys_bootcount.c that resetbc  won't work on nand
with min I/O size> 2048.

Check the boot-log entry's intergrity with checksum.

Signed-off-by: Qiyuan Zhang <zhang.github@outlook.com>
Link: https://github.com/openwrt/openwrt/pull/16070
Signed-off-by: Robert Marko <robimarko@gmail.com>
This commit is contained in:
Qiyuan Zhang 2024-08-02 10:57:51 -04:00 committed by Robert Marko
parent f96b3383d5
commit 5b3044e8e3

View File

@ -69,12 +69,10 @@ struct bootcounter {
uint32_t checksum;
};
static char page[2048];
int mtd_resetbc(const char *mtd)
{
struct mtd_info_user mtd_info;
struct bootcounter *curr = (struct bootcounter *)page;
struct bootcounter *curr = NULL;
unsigned int i;
unsigned int bc_offset_increment;
int last_count = 0;
@ -108,24 +106,23 @@ int mtd_resetbc(const char *mtd)
}
num_bc = mtd_info.size / bc_offset_increment;
curr = malloc(bc_offset_increment);
for (i = 0; i < num_bc; i++) {
pread(fd, curr, sizeof(*curr), i * bc_offset_increment);
pread(fd, curr, sizeof(struct bootcounter), i * bc_offset_increment);
/* Existing code assumes erase is to 0xff; left as-is (2019) */
if (curr->magic == 0xffffffff)
break;
if (curr->magic != BOOTCOUNT_MAGIC &&
curr->magic != 0xffffffff) {
DLOG_ERR("Unexpected magic %08x at offset %08x; aborting.",
curr->magic, i * bc_offset_increment);
if (curr->magic != BOOTCOUNT_MAGIC || curr->checksum != curr->magic + curr->count) {
DLOG_ERR("Unexpected boot-count log at offset %08x: magic %08x boot count %08x checksum %08x; aborting.",
i * bc_offset_increment, curr->magic, curr->count, curr->checksum);
retval = -2;
goto out;
}
if (curr->magic == 0xffffffff)
break;
last_count = curr->count;
}
@ -182,6 +179,7 @@ int mtd_resetbc(const char *mtd)
}
out:
if (curr != NULL) free(curr);
close(fd);
return retval;
}