Skip to content

bitwriter_grow_() correctly test for out-of-legit-range values #2 #866

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Open
ktmf01 wants to merge 1 commit into
base: master
Choose a base branch
from
Open

bitwriter_grow_() correctly test for out-of-legit-range values #2 #866

Changes from all commits
Commits
Show all changes
1 commit
Select commit
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
5 changes: 4 additions & 1 deletion src/libFLAC/bitwriter.c
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -112,6 +112,9 @@ FLAC__bool bitwriter_grow_(FLAC__BitWriter *bw, uint32_t bits_to_add)
uint32_t new_capacity;
bwword *new_buffer;

/* Refuse to allocate more words than this amount, based on largest possible metadata chunk size */
const uint32_t max_capacity = (((1u << FLAC__STREAM_METADATA_LENGTH_LEN) - 1) * 8 + FLAC__STREAM_METADATA_LENGTH_LEN + FLAC__BITS_PER_WORD - 1) / FLAC__BITS_PER_WORD;

FLAC__ASSERT(0 != bw);
FLAC__ASSERT(0 != bw->buffer);

Expand All @@ -124,7 +127,7 @@ FLAC__bool bitwriter_grow_(FLAC__BitWriter *bw, uint32_t bits_to_add)
if(bw->capacity >= new_capacity)
return true;

if(new_capacity * sizeof(bwword) > (1u << FLAC__STREAM_METADATA_LENGTH_LEN))
if(new_capacity > max_capacity)
/* Requested new capacity is larger than the largest possible metadata block,
* which is also larger than the largest sane framesize. That means something
* went very wrong somewhere and previous checks failed.
Expand Down
Loading