diff options
author | Jeremy Allison <jra@samba.org> | 2011-02-27 18:16:20 +0100 |
---|---|---|
committer | Karolin Seeger <kseeger@samba.org> | 2011-02-27 18:16:20 +0100 |
commit | 43babef991feedbe2acb77d27254d302ab107fa8 (patch) | |
tree | 3f1184591a69f886ef6ba84e4ea4000a155dee68 /lib/tevent | |
parent | a7aab3330f8bac43c86fdf3770daa0c42828a29c (diff) | |
download | samba-43babef991feedbe2acb77d27254d302ab107fa8.tar.gz |
Fix denial of service - memory corruption.
CVE-2011-0719
Fix bug #7949 (DoS in Winbind and smbd with many file descriptors open).
All current released versions of Samba are vulnerable to
a denial of service caused by memory corruption. Range
checks on file descriptors being used in the FD_SET macro
were not present allowing stack corruption. This can cause
the Samba code to crash or to loop attempting to select
on a bad file descriptor set.
A connection to a file share, or a local account is needed
to exploit this problem, either authenticated or unauthenticated
(guest connection).
Currently we do not believe this flaw is exploitable
beyond a crash or causing the code to loop, but on the
advice of our security reviewers we are releasing fixes
in case an exploit is discovered at a later date.
Diffstat (limited to 'lib/tevent')
-rw-r--r-- | lib/tevent/tevent_select.c | 10 | ||||
-rw-r--r-- | lib/tevent/tevent_standard.c | 5 |
2 files changed, 15 insertions, 0 deletions
diff --git a/lib/tevent/tevent_select.c b/lib/tevent/tevent_select.c index d97418991ae..890e0311c60 100644 --- a/lib/tevent/tevent_select.c +++ b/lib/tevent/tevent_select.c @@ -111,6 +111,11 @@ static struct tevent_fd *select_event_add_fd(struct tevent_context *ev, TALLOC_C struct select_event_context); struct tevent_fd *fde; + if (fd < 0 || fd >= FD_SETSIZE) { + errno = EBADF; + return NULL; + } + fde = tevent_common_add_fd(ev, mem_ctx, fd, flags, handler, private_data, handler_name, location); @@ -143,6 +148,11 @@ static int select_event_loop_select(struct select_event_context *select_ev, stru /* setup any fd events */ for (fde = select_ev->ev->fd_events; fde; fde = fde->next) { + if (fde->fd < 0 || fde->fd >= FD_SETSIZE) { + errno = EBADF; + return -1; + } + if (fde->flags & TEVENT_FD_READ) { FD_SET(fde->fd, &r_fds); } diff --git a/lib/tevent/tevent_standard.c b/lib/tevent/tevent_standard.c index c3f8b36e840..d4a00cc062a 100644 --- a/lib/tevent/tevent_standard.c +++ b/lib/tevent/tevent_standard.c @@ -457,6 +457,11 @@ static int std_event_loop_select(struct std_event_context *std_ev, struct timeva /* setup any fd events */ for (fde = std_ev->ev->fd_events; fde; fde = fde->next) { + if (fde->fd < 0 || fde->fd >= FD_SETSIZE) { + std_ev->exit_code = EBADF; + return -1; + } + if (fde->flags & TEVENT_FD_READ) { FD_SET(fde->fd, &r_fds); } |