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charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit X-Spamd-Result: default: False [-2.80 / 50.00]; BAYES_HAM(-3.00)[100.00%]; SUSPICIOUS_RECIPS(1.50)[]; NEURAL_HAM_LONG(-1.00)[-1.000]; NEURAL_HAM_SHORT(-0.20)[-1.000]; MIME_GOOD(-0.10)[text/plain]; TAGGED_RCPT(0.00)[]; FUZZY_RATELIMITED(0.00)[rspamd.com]; MIME_TRACE(0.00)[0:+]; RCPT_COUNT_TWELVE(0.00)[14]; ARC_NA(0.00)[]; RCVD_VIA_SMTP_AUTH(0.00)[]; FREEMAIL_TO(0.00)[gmail.com,linux.intel.com,kernel.org,ffwll.ch,linutronix.de,redhat.com,linuxfoundation.org,aol.com]; FREEMAIL_ENVRCPT(0.00)[aol.com,gmail.com]; TO_DN_SOME(0.00)[]; FROM_EQ_ENVFROM(0.00)[]; FROM_HAS_DN(0.00)[]; MID_RHS_MATCH_FROM(0.00)[]; RCVD_TLS_ALL(0.00)[]; RCVD_COUNT_TWO(0.00)[2]; TO_MATCH_ENVRCPT_ALL(0.00)[]; DKIM_SIGNED(0.00)[suse.de:s=susede2_rsa,suse.de:s=susede2_ed25519]; DBL_BLOCKED_OPENRESOLVER(0.00)[suse.de:mid,imap1.dmz-prg2.suse.org:helo] Hi Am 23.09.25 um 08:34 schrieb Thomas Zimmermann: > cc Ruben > > Am 22.09.25 um 19:43 schrieb Mehdi Ben Hadj Khelifa: >> Replace kmalloc with kmalloc array in drm/gud/gud_pipe.c since the >> calculation inside kmalloc is dynamic "width * height" and added >> u_char as the size of each element. >> >> Signed-off-by: Mehdi Ben Hadj Khelifa >> --- >>   drivers/gpu/drm/gud/gud_pipe.c | 2 +- >>   1 file changed, 1 insertion(+), 1 deletion(-) >> >> diff --git a/drivers/gpu/drm/gud/gud_pipe.c >> b/drivers/gpu/drm/gud/gud_pipe.c >> index 8d548d08f127..eeea0cb4c7aa 100644 >> --- a/drivers/gpu/drm/gud/gud_pipe.c >> +++ b/drivers/gpu/drm/gud/gud_pipe.c >> @@ -70,7 +70,7 @@ static size_t gud_xrgb8888_to_r124(u8 *dst, const >> struct drm_format_info *format >>       height = drm_rect_height(rect); >>       len = drm_format_info_min_pitch(format, 0, width) * height; >>   -    buf = kmalloc(width * height, GFP_KERNEL); >> +    buf = kmalloc_array(width * height, sizeof(u_char), GFP_KERNEL); u_char is more or less guaranteed to be 8 bit. So what's the point? There's a potential overflow in width * height. If anything, you want to call kmalloc_array(height, width). Best regards Thomas >>       if (!buf) >>           return 0; > -- -- Thomas Zimmermann Graphics Driver Developer SUSE Software Solutions Germany GmbH Frankenstrasse 146, 90461 Nuernberg, Germany GF: Ivo Totev, Andrew Myers, Andrew McDonald, Boudien Moerman HRB 36809 (AG Nuernberg)