diff options
| author | Mark Wielaard <mark@klomp.org> | 2018-06-10 16:59:12 +0200 |
|---|---|---|
| committer | Mark Wielaard <mark@klomp.org> | 2018-06-11 17:26:02 +0200 |
| commit | 340ce2c433b8033e57c0c23e9087ea15a349fd3e (patch) | |
| tree | ac5be8c563ab386a1303018480944a4e9011860c /libdw | |
| parent | 305211458a58a99b999639171c55724e3d9b51c0 (diff) | |
libdw: Break long or circular DIE ref chains in dwarf_[has]attr_integrate.
Bad DWARF could create a very long or circular DIE ref chain by linking
DW_AT_abstract_origin or DW_AT_specification to the DIE itself. Break
the chain after seeing a large number (16) of DIEs.
Signed-off-by: Mark Wielaard <mark@klomp.org>
Diffstat (limited to 'libdw')
| -rw-r--r-- | libdw/ChangeLog | 6 | ||||
| -rw-r--r-- | libdw/dwarf_attr_integrate.c | 4 | ||||
| -rw-r--r-- | libdw/dwarf_hasattr_integrate.c | 4 |
3 files changed, 10 insertions, 4 deletions
diff --git a/libdw/ChangeLog b/libdw/ChangeLog index 1195cf6e..07a1346b 100644 --- a/libdw/ChangeLog +++ b/libdw/ChangeLog @@ -1,3 +1,9 @@ +2018-06-10 Mark Wielaard <mark@klomp.org> + + * dwarf_attr_integrate.c (dwarf_attr_integrate): Stop after 16 DIE + ref chains. + * dwarf_hasattr_integrate.c (dwarf_hasattr_integrate): Likewise. + 2018-06-08 Mark Wielaard <mark@klomp.org> * dwarf_getabbrev.c (dwarf_getabbrev): Check die and offset. diff --git a/libdw/dwarf_attr_integrate.c b/libdw/dwarf_attr_integrate.c index 748d988d..fc068638 100644 --- a/libdw/dwarf_attr_integrate.c +++ b/libdw/dwarf_attr_integrate.c @@ -38,7 +38,7 @@ dwarf_attr_integrate (Dwarf_Die *die, unsigned int search_name, Dwarf_Attribute *result) { Dwarf_Die die_mem; - + int chain = 16; /* Largest DIE ref chain we will follow. */ do { Dwarf_Attribute *attr = INTUSE(dwarf_attr) (die, search_name, result); @@ -53,7 +53,7 @@ dwarf_attr_integrate (Dwarf_Die *die, unsigned int search_name, die = INTUSE(dwarf_formref_die) (attr, &die_mem); } - while (die != NULL); + while (die != NULL && chain-- != 0); /* Not NULL if it didn't have abstract_origin and specification attributes. If it is a split CU then see if the skeleton diff --git a/libdw/dwarf_hasattr_integrate.c b/libdw/dwarf_hasattr_integrate.c index 4d4b4c54..1d946280 100644 --- a/libdw/dwarf_hasattr_integrate.c +++ b/libdw/dwarf_hasattr_integrate.c @@ -37,7 +37,7 @@ int dwarf_hasattr_integrate (Dwarf_Die *die, unsigned int search_name) { Dwarf_Die die_mem; - + int chain = 16; /* Largest DIE ref chain we will follow. */ do { if (INTUSE(dwarf_hasattr) (die, search_name)) @@ -53,7 +53,7 @@ dwarf_hasattr_integrate (Dwarf_Die *die, unsigned int search_name) die = INTUSE(dwarf_formref_die) (attr, &die_mem); } - while (die != NULL); + while (die != NULL && chain-- != 0); /* Not NULL if it didn't have abstract_origin and specification attributes. If it is a split CU then see if the skeleton |