| Message ID | 20190712233741.23276-1-rkx1209dev@gmail.com |
|---|---|
| State | New |
| Headers | show |
| Series | [v2] libiberty: Check zero value shstrndx in simple-object-elf.c | expand |
Oh. I missed a ChangeLog entry. Hold on... I'll send v3 patch. Thanks 2019年7月12日(金) 19:37 Ren Kimura <rkx1209dev@gmail.com>: > > This patch fixes a Bug 90924. > simple_object_elf functions don't load section table 0 of ELF file, which is not a useful. > However If e_shstrndx in ELF header points to a section table 0 (i.e. e_shstrndx == 0), a calculation of offset to string section table causes integer overflow at every line "(eor->shstrndx - 1)". > A result becomes negative value (unsigned int)-1 and causes memory corruption. > > Signed-off-by: Ren Kimura <rkx1209dev@gmail.com> > --- > libiberty/simple-object-elf.c | 10 +++++++++- > 1 file changed, 9 insertions(+), 1 deletion(-) > > diff --git a/libiberty/simple-object-elf.c b/libiberty/simple-object-elf.c > index 22c9ae7ed2d..9c561632bc5 100644 > --- a/libiberty/simple-object-elf.c > +++ b/libiberty/simple-object-elf.c > @@ -548,7 +548,15 @@ simple_object_elf_match (unsigned char header[SIMPLE_OBJECT_MATCH_HEADER_LEN], > XDELETE (eor); > return NULL; > } > - > + > + if (eor->shstrndx == 0) > + { > + *errmsg = "invalid ELF shstrndx == 0"; > + *err = 0; > + XDELETE (eor); > + return NULL; > + } > + > return (void *) eor; > } > > -- > 2.19.1 >
diff --git a/libiberty/simple-object-elf.c b/libiberty/simple-object-elf.c index 22c9ae7ed2d..9c561632bc5 100644 --- a/libiberty/simple-object-elf.c +++ b/libiberty/simple-object-elf.c @@ -548,7 +548,15 @@ simple_object_elf_match (unsigned char header[SIMPLE_OBJECT_MATCH_HEADER_LEN], XDELETE (eor); return NULL; } - + + if (eor->shstrndx == 0) + { + *errmsg = "invalid ELF shstrndx == 0"; + *err = 0; + XDELETE (eor); + return NULL; + } + return (void *) eor; }
This patch fixes a Bug 90924. simple_object_elf functions don't load section table 0 of ELF file, which is not a useful. However If e_shstrndx in ELF header points to a section table 0 (i.e. e_shstrndx == 0), a calculation of offset to string section table causes integer overflow at every line "(eor->shstrndx - 1)". A result becomes negative value (unsigned int)-1 and causes memory corruption. Signed-off-by: Ren Kimura <rkx1209dev@gmail.com> --- libiberty/simple-object-elf.c | 10 +++++++++- 1 file changed, 9 insertions(+), 1 deletion(-)