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
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
copy.c
#include "cache.h"
int copy_fd(int ifd, int ofd)
{
while (1) {
char buffer[8192];
ssize_t len = xread(ifd, buffer, sizeof(buffer));
if (!len)
break;
if (len < 0)
return COPY_READ_ERROR;
if (write_in_full(ofd, buffer, len) < 0)
return COPY_WRITE_ERROR;
}
return 0;
}
static int copy_times(const char *dst, const char *src)
{
struct stat st;
struct utimbuf times;
if (stat(src, &st) < 0)
return -1;
times.actime = st.st_atime;
times.modtime = st.st_mtime;
if (utime(dst, ×) < 0)
return -1;
return 0;
}
int copy_file(const char *dst, const char *src, int mode)
{
int fdi, fdo, status;
mode = (mode & 0111) ? 0777 : 0666;
if ((fdi = open(src, O_RDONLY)) < 0)
return fdi;
if ((fdo = open(dst, O_WRONLY | O_CREAT | O_EXCL, mode)) < 0) {
close(fdi);
return fdo;
}
status = copy_fd(fdi, fdo);
switch (status) {
case COPY_READ_ERROR:
error_errno("copy-fd: read returned");
break;
case COPY_WRITE_ERROR:
error_errno("copy-fd: write returned");
break;
}
close(fdi);
if (close(fdo) != 0)
return error_errno("%s: close error", dst);
if (!status && adjust_shared_perm(dst))
return -1;
return status;
}
int copy_file_with_time(const char *dst, const char *src, int mode)
{
int status = copy_file(dst, src, mode);
if (!status)
return copy_times(dst, src);
return status;
}
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