modpost: fix off by one in is_executable_section()

Dan Carpenter · masahir0y · commit 3a3f1e573a10 · 2023-06-08T22:50:04.000+09:00
The > comparison should be >= to prevent an out of bounds array access. Fixes: 52dc059 ("modpost: handle relocations mismatch in __ex_table.") Signed-off-by: Dan Carpenter <dan.carpenter@linaro.org> Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
diff --git a/scripts/mod/modpost.c b/scripts/mod/modpost.c
@@ -1141,7 +1141,7 @@ static Elf_Sym *find_tosym(struct elf_info *elf, Elf_Addr addr, Elf_Sym *sym)
 
 static bool is_executable_section(struct elf_info *elf, unsigned int secndx)
 {
-	if (secndx > elf->num_sections)
+	if (secndx >= elf->num_sections)
 		return false;
 
 	return (elf->sechdrs[secndx].sh_flags & SHF_EXECINSTR) != 0;

Original file line number	Diff line number	Diff line change
`@@ -1141,7 +1141,7 @@ static Elf_Sym find_tosym(struct elf_info elf, Elf_Addr addr, Elf_Sym *sym)`
`1141`	`1141`
`1142`	`1142`	`static bool is_executable_section(struct elf_info *elf, unsigned int secndx)`
`1143`	`1143`	`{`
`1144`		`- if (secndx > elf->num_sections)`
	`1144`	`+ if (secndx >= elf->num_sections)`
`1145`	`1145`	`return false;`
`1146`	`1146`
`1147`	`1147`	`return (elf->sechdrs[secndx].sh_flags & SHF_EXECINSTR) != 0;`