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| author | Hannes Frederic Sowa <hannes@stressinduktion.org> | 2016-02-03 02:11:03 +0100 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2016-02-08 10:30:42 -0500 |
| commit | 415e3d3e90ce9e18727e8843ae343eda5a58fad6 (patch) | |
| tree | 529751765d40af6f6cfcafdc1c92b1dcafb5c8da /net/unix/af_unix.c | |
| parent | aa7b45378059a3eba1529d76f6d0b367ba614646 (diff) | |
| download | blackbird-op-linux-415e3d3e90ce9e18727e8843ae343eda5a58fad6.tar.gz blackbird-op-linux-415e3d3e90ce9e18727e8843ae343eda5a58fad6.zip | |
unix: correctly track in-flight fds in sending process user_struct
The commit referenced in the Fixes tag incorrectly accounted the number
of in-flight fds over a unix domain socket to the original opener
of the file-descriptor. This allows another process to arbitrary
deplete the original file-openers resource limit for the maximum of
open files. Instead the sending processes and its struct cred should
be credited.
To do so, we add a reference counted struct user_struct pointer to the
scm_fp_list and use it to account for the number of inflight unix fds.
Fixes: 712f4aad406bb1 ("unix: properly account for FDs passed over unix sockets")
Reported-by: David Herrmann <dh.herrmann@gmail.com>
Cc: David Herrmann <dh.herrmann@gmail.com>
Cc: Willy Tarreau <w@1wt.eu>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net/unix/af_unix.c')
| -rw-r--r-- | net/unix/af_unix.c | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/net/unix/af_unix.c b/net/unix/af_unix.c index 49d5093eb055..29be035f9c65 100644 --- a/net/unix/af_unix.c +++ b/net/unix/af_unix.c @@ -1496,7 +1496,7 @@ static void unix_detach_fds(struct scm_cookie *scm, struct sk_buff *skb) UNIXCB(skb).fp = NULL; for (i = scm->fp->count-1; i >= 0; i--) - unix_notinflight(scm->fp->fp[i]); + unix_notinflight(scm->fp->user, scm->fp->fp[i]); } static void unix_destruct_scm(struct sk_buff *skb) @@ -1561,7 +1561,7 @@ static int unix_attach_fds(struct scm_cookie *scm, struct sk_buff *skb) return -ENOMEM; for (i = scm->fp->count - 1; i >= 0; i--) - unix_inflight(scm->fp->fp[i]); + unix_inflight(scm->fp->user, scm->fp->fp[i]); return max_level; } |
