| 1 | From 13f54e513024fc8224065515d9c664135aba1848 Mon Sep 17 00:00:00 2001 |
| 2 | From: Adam Jackson <ajax@redhat.com> |
| 3 | Date: Mon, 10 Nov 2014 12:13:40 -0500 |
| 4 | Subject: [PATCH 24/33] glx: Add safe_{add,mul,pad} (v3) [CVE-2014-8093 4/6] |
| 5 | |
| 6 | These are paranoid about integer overflow, and will return -1 if their |
| 7 | operation would overflow a (signed) integer or if either argument is |
| 8 | negative. |
| 9 | |
| 10 | Note that RenderLarge requests are sized with a uint32_t so in principle |
| 11 | this could be sketchy there, but dix limits bigreqs to 128M so you |
| 12 | shouldn't ever notice, and honestly if you're sending more than 2G of |
| 13 | rendering commands you're already doing something very wrong. |
| 14 | |
| 15 | v2: Use INT_MAX for consistency with the rest of the server (jcristau) |
| 16 | v3: Reject negative arguments (anholt) |
| 17 | |
| 18 | Reviewed-by: Keith Packard <keithp@keithp.com> |
| 19 | Reviewed-by: Julien Cristau <jcristau@debian.org> |
| 20 | Reviewed-by: Michal Srb <msrb@suse.com> |
| 21 | Reviewed-by: Andy Ritger <aritger@nvidia.com> |
| 22 | Signed-off-by: Adam Jackson <ajax@redhat.com> |
| 23 | Signed-off-by: Alan Coopersmith <alan.coopersmith@oracle.com> |
| 24 | --- |
| 25 | glx/glxserver.h | 41 +++++++++++++++++++++++++++++++++++++++++ |
| 26 | 1 file changed, 41 insertions(+) |
| 27 | |
| 28 | --- a/glx/glxserver.h |
| 29 | +++ b/glx/glxserver.h |
| 30 | @@ -230,6 +230,47 @@ extern void glxSwapQueryServerStringRepl |
| 31 | * Routines for computing the size of variably-sized rendering commands. |
| 32 | */ |
| 33 | |
| 34 | +static _X_INLINE int |
| 35 | +safe_add(int a, int b) |
| 36 | +{ |
| 37 | + if (a < 0 || b < 0) |
| 38 | + return -1; |
| 39 | + |
| 40 | + if (INT_MAX - a < b) |
| 41 | + return -1; |
| 42 | + |
| 43 | + return a + b; |
| 44 | +} |
| 45 | + |
| 46 | +static _X_INLINE int |
| 47 | +safe_mul(int a, int b) |
| 48 | +{ |
| 49 | + if (a < 0 || b < 0) |
| 50 | + return -1; |
| 51 | + |
| 52 | + if (a == 0 || b == 0) |
| 53 | + return 0; |
| 54 | + |
| 55 | + if (a > INT_MAX / b) |
| 56 | + return -1; |
| 57 | + |
| 58 | + return a * b; |
| 59 | +} |
| 60 | + |
| 61 | +static _X_INLINE int |
| 62 | +safe_pad(int a) |
| 63 | +{ |
| 64 | + int ret; |
| 65 | + |
| 66 | + if (a < 0) |
| 67 | + return -1; |
| 68 | + |
| 69 | + if ((ret = safe_add(a, 3)) < 0) |
| 70 | + return -1; |
| 71 | + |
| 72 | + return ret & (GLuint)~3; |
| 73 | +} |
| 74 | + |
| 75 | extern int __glXTypeSize(GLenum enm); |
| 76 | extern int __glXImageSize(GLenum format, GLenum type, |
| 77 | GLenum target, GLsizei w, GLsizei h, GLsizei d, |