Fix integer wrap sanitisation.

Test: make check
Bug: 239630493
Bug: 242096164
Change-Id: I232155e7f7a54271a6a3e3a7cd91ed6bbabc051f
Merged-In: I232155e7f7a54271a6a3e3a7cd91ed6bbabc051f
(cherry picked from commit 05dec6d182)
This commit is contained in:
Mike McTernan 2022-07-22 11:44:33 +01:00
parent d78db83214
commit 61e10c9c53

View file

@ -124,9 +124,15 @@ uint32_t fdt_next_tag(const void *fdt, int startoffset, int *nextoffset)
lenp = fdt_offset_ptr(fdt, offset, sizeof(*lenp));
if (!lenp)
return FDT_END; /* premature end */
/* skip-name offset, length and value */
offset += sizeof(struct fdt_property) - FDT_TAGSIZE
+ fdt32_to_cpu(*lenp);
/* skip-name offset, length */
offset += sizeof(struct fdt_property) - FDT_TAGSIZE;
if (!fdt_offset_ptr(fdt, offset, fdt32_to_cpu(*lenp)))
return FDT_END; /* premature end */
/* skip value */
offset += fdt32_to_cpu(*lenp);
break;
case FDT_END:
@ -138,7 +144,7 @@ uint32_t fdt_next_tag(const void *fdt, int startoffset, int *nextoffset)
return FDT_END;
}
if (!fdt_offset_ptr(fdt, startoffset, offset - startoffset))
if (offset <= startoffset || !fdt_offset_ptr(fdt, startoffset, offset - startoffset))
return FDT_END; /* premature end */
*nextoffset = FDT_TAGALIGN(offset);