mirrors/git
0
0
Fork 0
mirror of https://github.com/git/git.git synced 2024-11-24 18:33:43 +08:00
Code Issues Packages Projects Releases Wiki Activity

Merge branch 'jk/diagnose-config-mmap-failure'

Browse Source 
The configuration reader/writer uses mmap(2) interface to access
the files; when we find a directory, it barfed with "Out of memory?".

* jk/diagnose-config-mmap-failure:
  xmmap(): drop "Out of memory?"
  config.c: rewrite ENODEV into EISDIR when mmap fails
  config.c: avoid xmmap error messages
  config.c: fix mmap leak when writing config
  read-cache.c: drop PROT_WRITE from mmap of index
This commit is contained in:
Junio C Hamano 2015-06-11 09:29:55 -07:00
commit dee47925c1
4 changed files with 29 additions and 11 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

20
config.c
View File

@ -1939,6 +1939,8 @@ int git_config_set_multivar_in_file(const char *config_filename,
int ret;
struct lock_file *lock = NULL;
char *filename_buf = NULL;
char *contents = NULL;
size_t contents_sz;
/* parse-key returns negative; flip the sign to feed exit(3) */
ret = 0 - git_config_parse_key(key, &store.key, &store.baselen);
@ -1988,8 +1990,7 @@ int git_config_set_multivar_in_file(const char *config_filename,
goto write_err_out;
} else {
struct stat st;
char *contents;
size_t contents_sz, copy_begin, copy_end;
size_t copy_begin, copy_end;
int i, new_line = 0;
if (value_regex == NULL)
@ -2052,8 +2053,17 @@ int git_config_set_multivar_in_file(const char *config_filename,
fstat(in_fd, &st);
contents_sz = xsize_t(st.st_size);
contents = xmmap(NULL, contents_sz, PROT_READ,
contents = xmmap_gently(NULL, contents_sz, PROT_READ,
MAP_PRIVATE, in_fd, 0);
if (contents == MAP_FAILED) {
if (errno == ENODEV && S_ISDIR(st.st_mode))
errno = EISDIR;
error("unable to mmap '%s': %s",
config_filename, strerror(errno));
ret = CONFIG_INVALID_FILE;
contents = NULL;
goto out_free;
}
close(in_fd);
if (chmod(lock->filename.buf, st.st_mode & 07777) < 0) {
@ -2108,8 +2118,6 @@ int git_config_set_multivar_in_file(const char *config_filename,
contents_sz - copy_begin) <
contents_sz - copy_begin)
goto write_err_out;
munmap(contents, contents_sz);
}
if (commit_lock_file(lock) < 0) {
@ -2135,6 +2143,8 @@ out_free:
if (lock)
rollback_lock_file(lock);
free(filename_buf);
if (contents)
munmap(contents, contents_sz);
return ret;
write_err_out:

1
git-compat-util.h
View File

@ -718,6 +718,7 @@ extern char *xstrndup(const char *str, size_t len);
extern void *xrealloc(void *ptr, size_t size);
extern void *xcalloc(size_t nmemb, size_t size);
extern void *xmmap(void *start, size_t length, int prot, int flags, int fd, off_t offset);
extern void *xmmap_gently(void *start, size_t length, int prot, int flags, int fd, off_t offset);
extern ssize_t xread(int fd, void *buf, size_t len);
extern ssize_t xwrite(int fd, const void *buf, size_t len);
extern ssize_t xpread(int fd, void *buf, size_t len, off_t offset);

2
read-cache.c
View File

@ -1562,7 +1562,7 @@ int do_read_index(struct index_state *istate, const char *path, int must_exist)
if (mmap_size < sizeof(struct cache_header) + 20)
die("index file smaller than expected");
mmap = xmmap(NULL, mmap_size, PROT_READ | PROT_WRITE, MAP_PRIVATE, fd, 0);
mmap = xmmap(NULL, mmap_size, PROT_READ, MAP_PRIVATE, fd, 0);
if (mmap == MAP_FAILED)
die_errno("unable to map index file");
close(fd);

13
sha1_file.c
View File

@ -707,7 +707,7 @@ static void mmap_limit_check(size_t length)
(uintmax_t)length, (uintmax_t)limit);
}
void *xmmap(void *start, size_t length,
void *xmmap_gently(void *start, size_t length,
int prot, int flags, int fd, off_t offset)
{
void *ret;
@ -719,12 +719,19 @@ void *xmmap(void *start, size_t length,
return NULL;
release_pack_memory(length);
ret = mmap(start, length, prot, flags, fd, offset);
if (ret == MAP_FAILED)
die_errno("Out of memory? mmap failed");
}
return ret;
}
void *xmmap(void *start, size_t length,
int prot, int flags, int fd, off_t offset)
{
void *ret = xmmap_gently(start, length, prot, flags, fd, offset);
if (ret == MAP_FAILED)
die_errno("mmap failed");
return ret;
}
void close_pack_windows(struct packed_git *p)
{
while (p->windows) {