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#include <assert.h>
#include <stdio.h>
#include <stdlib.h>
#include <sys/types.h>
#include <libelfu/libelfu.h>
static int isOverlapping(size_t off1, size_t sz1, size_t off2, size_t sz2)
{
size_t end1 = off1 + sz1;
size_t end2 = off2 + sz2;
if (off2 >= off1 && off2 < end1) {
return 1;
} else if (off1 >= off2 && off1 < end2) {
return 1;
} else {
return 0;
}
}
static int cmpScnOffs(const void *ms1, const void *ms2)
{
assert(ms1);
assert(ms2);
ElfuScn *s1 = *(ElfuScn**)ms1;
ElfuScn *s2 = *(ElfuScn**)ms2;
assert(s1);
assert(s2);
if (s1->shdr.sh_offset < s2->shdr.sh_offset) {
return -1;
} else if (s1->shdr.sh_offset == s2->shdr.sh_offset) {
return 0;
} else /* if (s1->shdr.sh_offset > s2->shdr.sh_offset) */ {
return 1;
}
}
int elfu_modelCheck(ElfuElf *me)
{
ElfuScn *ms;
size_t numSecs;
ElfuScn **sortedSecs;
size_t i;
/* Sort sections by offset in file */
numSecs = elfu_countSections(me);
sortedSecs = malloc(numSecs * sizeof(*sortedSecs));
if (!sortedSecs) {
fprintf(stderr, "elfu_check: Failed to allocate memory.\n");
}
i = 0;
CIRCLEQ_FOREACH(ms, &me->scnList, elem) {
sortedSecs[i] = ms;
i++;
}
assert(i = numSecs);
qsort(sortedSecs, numSecs, sizeof(*sortedSecs), cmpScnOffs);
/* Check for overlapping sections */
for (i = 0; i < numSecs - 1; i++) {
if (sortedSecs[i]->shdr.sh_offset + elfu_scnSizeFile(&sortedSecs[i]->shdr)
> sortedSecs[i+1]->shdr.sh_offset) {
fprintf(stderr, "elfu_check: Found overlapping sections: %s and %s.\n",
elfu_modelScnName(me, sortedSecs[i]),
elfu_modelScnName(me, sortedSecs[i+1]));
}
}
/* Check for sections overlapping with EHDR */
for (i = 0; i < numSecs; i++) {
if (sortedSecs[i]->shdr.sh_offset < me->ehdr.e_ehsize) {
fprintf(stderr, "elfu_check: Found section overlapping with EHDR: %s.\n",
elfu_modelScnName(me, sortedSecs[i]));
}
}
/* Check for sections overlapping with PHDRs */
for (i = 0; i < numSecs; i++) {
if (isOverlapping(sortedSecs[i]->shdr.sh_offset,
elfu_scnSizeFile(&sortedSecs[i]->shdr),
me->ehdr.e_phoff,
me->ehdr.e_phentsize * me->ehdr.e_phnum)) {
fprintf(stderr, "elfu_check: Found section overlapping with PHDRs: %s.\n",
elfu_modelScnName(me, sortedSecs[i]));
}
}
free(sortedSecs);
return 0;
}
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