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Revision 447ac906e189535e77dcb1f4bbe3f1bc917d4c12 authored by Patrick Steinhardt on 01 December 2022, 14:45:31 UTC, committed by Junio C Hamano on 05 December 2022, 06:14:16 UTC 
attr: fix out-of-bounds read with unreasonable amount of patterns
 
The `struct attr_stack` tracks the stack of all patterns together with
their attributes. When parsing a gitattributes file that has more than
2^31 such patterns though we may trigger multiple out-of-bounds reads on
64 bit platforms. This is because while the `num_matches` variable is an
unsigned integer, we always use a signed integer to iterate over them.

I have not been able to reproduce this issue due to memory constraints
on my systems. But despite the out-of-bounds reads, the worst thing that
can seemingly happen is to call free(3P) with a garbage pointer when
calling `attr_stack_free()`.

Fix this bug by using unsigned integers to iterate over the array. While
this makes the iteration somewhat awkward when iterating in reverse, it
is at least better than knowingly running into an out-of-bounds read.
While at it, convert the call to `ALLOC_GROW` to use `ALLOC_GROW_BY`
instead.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
1 parent 34ace8b
Raw File
connect.h 
#ifndef CONNECT_H
#define CONNECT_H

#include "protocol.h"

#define CONNECT_VERBOSE       (1u << 0)
#define CONNECT_DIAG_URL      (1u << 1)
#define CONNECT_IPV4          (1u << 2)
#define CONNECT_IPV6          (1u << 3)
struct child_process *git_connect(int fd[2], const char *url, const char *prog, int flags);
int finish_connect(struct child_process *conn);
int git_connection_is_socket(struct child_process *conn);
int server_supports(const char *feature);
int parse_feature_request(const char *features, const char *feature);
const char *server_feature_value(const char *feature, int *len_ret);
int url_is_local_not_ssh(const char *url);

struct packet_reader;
enum protocol_version discover_version(struct packet_reader *reader);

int server_supports_hash(const char *desired, int *feature_supported);
const char *parse_feature_value(const char *feature_list, const char *feature, int *lenp, int *offset);
int server_supports_v2(const char *c, int die_on_error);
int server_feature_v2(const char *c, const char **v);
int server_supports_feature(const char *c, const char *feature,
			    int die_on_error);

void check_stateless_delimiter(int stateless_rpc,
			       struct packet_reader *reader,
			       const char *error);

#endif
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