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charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit X-Rspamd-Action: no action X-Rspamd-Server: rspamd2.dmz-prg2.suse.org X-Spamd-Result: default: False [-4.51 / 50.00]; BAYES_HAM(-3.00)[100.00%]; NEURAL_HAM_LONG(-1.00)[-1.000]; NEURAL_HAM_SHORT(-0.20)[-1.000]; R_DKIM_ALLOW(-0.20)[suse.de:s=susede2_rsa,suse.de:s=susede2_ed25519]; MIME_GOOD(-0.10)[text/plain]; MX_GOOD(-0.01)[]; DKIM_SIGNED(0.00)[suse.de:s=susede2_rsa,suse.de:s=susede2_ed25519]; URIBL_BLOCKED(0.00)[imap1.dmz-prg2.suse.org:helo,imap1.dmz-prg2.suse.org:rdns,intel.com:email,suse.de:dkim,suse.de:mid,suse.de:email,linuxfoundation.org:email,suse.com:url]; FUZZY_RATELIMITED(0.00)[rspamd.com]; RBL_SPAMHAUS_BLOCKED_OPENRESOLVER(0.00)[2a07:de40:b281:104:10:150:64:97:from]; TO_DN_SOME(0.00)[]; TO_MATCH_ENVRCPT_ALL(0.00)[]; MIME_TRACE(0.00)[0:+]; ARC_NA(0.00)[]; FREEMAIL_ENVRCPT(0.00)[gmail.com]; RCVD_TLS_ALL(0.00)[]; SPAMHAUS_XBL(0.00)[2a07:de40:b281:104:10:150:64:97:from]; RCVD_COUNT_TWO(0.00)[2]; DNSWL_BLOCKED(0.00)[2a07:de40:b281:106:10:150:64:167:received,2a07:de40:b281:104:10:150:64:97:from]; FROM_EQ_ENVFROM(0.00)[]; FROM_HAS_DN(0.00)[]; FREEMAIL_CC(0.00)[vger.kernel.org,linux.intel.com,kernel.org,gmail.com,ffwll.ch]; MID_RHS_MATCH_FROM(0.00)[]; RECEIVED_SPAMHAUS_BLOCKED_OPENRESOLVER(0.00)[2a07:de40:b281:106:10:150:64:167:received]; RCPT_COUNT_SEVEN(0.00)[8]; DKIM_TRACE(0.00)[suse.de:+]; RCVD_VIA_SMTP_AUTH(0.00)[]; DBL_BLOCKED_OPENRESOLVER(0.00)[suse.de:dkim,suse.de:mid,suse.de:email,imap1.dmz-prg2.suse.org:helo,imap1.dmz-prg2.suse.org:rdns,suse.com:url,linuxfoundation.org:email] X-Rspamd-Queue-Id: 796004D24C X-Spam-Flag: NO X-Spam-Score: -4.51 X-Spam-Level: Am 24.03.26 um 17:42 schrieb Greg Kroah-Hartman: > The drm compat ioctl path takes a user controlled pointer, and then > dereferences it into a table of function pointers, the signature method > of spectre problems. Fix this up by calling array_index_nospec() on the > index to the function pointer list. > > Cc: Maarten Lankhorst > Cc: Maxime Ripard > Cc: Thomas Zimmermann > Cc: David Airlie > Cc: Simona Vetter > Cc: stable > Assisted-by: gkh_clanker_2000 > Signed-off-by: Greg Kroah-Hartman > --- > My scripts caught this codepath as not being "protected" for the > old-school spectre attack. I don't know how realistic it is, but it > seems like this is the correct thing to be doing for a 32bit ioctl on > the drm path, as "local" users can make these. Seems reasonable. Acked-by: Thomas Zimmermann > > drivers/gpu/drm/drm_ioc32.c | 2 ++ > 1 file changed, 2 insertions(+) > > diff --git a/drivers/gpu/drm/drm_ioc32.c b/drivers/gpu/drm/drm_ioc32.c > index e6b5b06de148..f3e40d1e6098 100644 > --- a/drivers/gpu/drm/drm_ioc32.c > +++ b/drivers/gpu/drm/drm_ioc32.c > @@ -28,6 +28,7 @@ > * IN THE SOFTWARE. > */ > #include > +#include > #include > #include > > @@ -374,6 +375,7 @@ long drm_compat_ioctl(struct file *filp, unsigned int cmd, unsigned long arg) > if (nr >= ARRAY_SIZE(drm_compat_ioctls)) > return drm_ioctl(filp, cmd, arg); > > + nr = array_index_nospec(nr, ARRAY_SIZE(drm_compat_ioctls)); > fn = drm_compat_ioctls[nr].fn; > if (!fn) > return drm_ioctl(filp, cmd, arg); -- -- Thomas Zimmermann Graphics Driver Developer SUSE Software Solutions Germany GmbH Frankenstr. 146, 90461 Nürnberg, Germany, www.suse.com GF: Jochen Jaser, Andrew McDonald, Werner Knoblich, (HRB 36809, AG Nürnberg)