raster pushed a commit to branch master.
http://git.enlightenment.org/core/efl.git/commit/?id=a5c8e883d8f9b3389e9a6233ba79c47df3bdc420
commit a5c8e883d8f9b3389e9a6233ba79c47df3bdc420
Author: Carsten Haitzler (Rasterman) <ras...@rasterman.com>
Date: Wed Aug 30 12:03:41 2017 +0900
eina mmap safety - only map zeropages if it's an eina file that sigbuses
restrict mapping /dev/zero to only eina files having a sigbus
reported. the mmap was before all our file access used eina_file i
think thus the raw mmap of it. now walk all eina files and find the
candidate and only then if it exists flag is as having a faulty i/o
backing and map the zerto pages then return, otherwise call abort.
more restricted mapping and perhaps a fix for not trapping non-efl
issues.
@fix
---
src/lib/eina/eina_file.c | 15 +++++++--------
src/lib/eina/eina_mmap.c | 43 ++++++++++++++++++++++++++-----------------
src/lib/eina/eina_private.h | 2 +-
3 files changed, 34 insertions(+), 26 deletions(-)
diff --git a/src/lib/eina/eina_file.c b/src/lib/eina/eina_file.c
index 7e154db0a0..c2c7f8f4aa 100644
--- a/src/lib/eina/eina_file.c
+++ b/src/lib/eina/eina_file.c
@@ -418,30 +418,28 @@ _eina_file_mmap_faulty_one(void *addr, long page_size,
return EINA_FALSE;
}
-void
+Eina_Bool
eina_file_mmap_faulty(void *addr, long page_size)
{
Eina_File_Map *m;
Eina_File *f;
Eina_Iterator *itf;
Eina_Iterator *itm;
+ Eina_Bool faulty = EINA_FALSE;
- /* NOTE: I actually don't know if other thread are running, I will try to
take the lock.
- It may be possible that if other thread are not running and they were in
the middle of
- accessing an Eina_File this lock are still taken and we will result as a
deadlock. */
eina_lock_take(&_eina_file_lock_cache);
itf = eina_hash_iterator_data_new(_eina_file_cache);
EINA_ITERATOR_FOREACH(itf, f)
{
- Eina_Bool faulty = EINA_FALSE;
-
eina_lock_take(&f->lock);
if (f->global_map != MAP_FAILED)
{
- if ((unsigned char *) addr < (((unsigned char *)f->global_map) +
f->length) &&
- (((unsigned char *) addr) + page_size) >= (unsigned char *)
f->global_map)
+ if ((unsigned char *)addr <
+ (((unsigned char *)f->global_map) + f->length) &&
+ (((unsigned char *)addr) + page_size) >=
+ (unsigned char *)f->global_map)
{
f->global_faulty = EINA_TRUE;
faulty = EINA_TRUE;
@@ -477,6 +475,7 @@ eina_file_mmap_faulty(void *addr, long page_size)
eina_iterator_free(itf);
eina_lock_release(&_eina_file_lock_cache);
+ return faulty;
}
/* ================================================================ *
diff --git a/src/lib/eina/eina_mmap.c b/src/lib/eina/eina_mmap.c
index d6d5281515..11d8804759 100644
--- a/src/lib/eina/eina_mmap.c
+++ b/src/lib/eina/eina_mmap.c
@@ -129,26 +129,35 @@ _eina_mmap_safe_sigbus(int sig, siginfo_t *siginfo, void
*ptr)
}
}
}
- /* send this to stderr - not eina_log. Specifically want this on stderr */
- fprintf(stderr,
- "EINA: Data at address 0x%lx is invalid. Replacing with zero
page.\n",
- (unsigned long)addr);
- /* align address to the lower page boundary */
- addr = (unsigned char *)((long)addr & (~(_eina_mmap_pagesize - 1)));
- /* mmap a pzge of zero's from /dev/zero in there */
- if (mmap(addr, _eina_mmap_pagesize,
- PROT_READ | PROT_WRITE | PROT_EXEC,
- MAP_PRIVATE | MAP_FIXED,
- _eina_mmap_zero_fd, 0) == MAP_FAILED)
+ // Look into mmaped Eina_File if it was one of them, mark it as having
+ // I/O errors and then mmap a zero page in place here
+ if (eina_file_mmap_faulty(addr, _eina_mmap_pagesize))
{
- /* mmap of /dev/zero failed :( */
- perror("mmap");
- ERR("Failed to mmap() /dev/zero in place of page. SIGBUS!!!");
- errno = perrno;
+ // Send this to stderr not eina_log. Specifically want this on stderr
+ fprintf(stderr,
+ "EINA: Data at address 0x%lx is invalid. "
+ "Replacing with zero page.\n",
+ (unsigned long)addr);
+ /* align address to the lower page boundary */
+ addr = (unsigned char *)((long)addr & (~(_eina_mmap_pagesize - 1)));
+ /* mmap a pzge of zero's from /dev/zero in there */
+ if (mmap(addr, _eina_mmap_pagesize,
+ PROT_READ | PROT_WRITE | PROT_EXEC,
+ MAP_PRIVATE | MAP_FIXED,
+ _eina_mmap_zero_fd, 0) == MAP_FAILED)
+ {
+ /* mmap of /dev/zero failed :( */
+ perror("mmap");
+ ERR("Failed to mmap() /dev/zero in place of page. SIGBUS!!!");
+ errno = perrno;
+ abort();
+ }
+ }
+ else
+ {
+ ERR("Regular SIGBUS not in an eina_file mmaped file");
abort();
}
- /* Look into mmaped Eina_File if it was one of them, just to remember for
later request */
- eina_file_mmap_faulty(addr, _eina_mmap_pagesize);
/* restore previous errno */
errno = perrno;
}
diff --git a/src/lib/eina/eina_private.h b/src/lib/eina/eina_private.h
index d032f84fbd..745364a2e5 100644
--- a/src/lib/eina/eina_private.h
+++ b/src/lib/eina/eina_private.h
@@ -136,7 +136,7 @@ void eina_log_threads_shutdown(void);
void eina_cpu_count_internal(void);
-void eina_file_mmap_faulty(void *addr, long page_size);
+Eina_Bool eina_file_mmap_faulty(void *addr, long page_size);
#ifndef EINA_FREEQ_H_
typedef struct _Eina_FreeQ Eina_FreeQ;
--
