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RCVD_TLS_ALL(0.00)[]; RCVD_COUNT_TWO(0.00)[2]; FROM_EQ_ENVFROM(0.00)[]; FROM_HAS_DN(0.00)[]; TO_DN_SOME(0.00)[]; MID_RHS_MATCH_FROM(0.00)[]; TAGGED_RCPT(0.00)[]; RECEIVED_SPAMHAUS_BLOCKED_OPENRESOLVER(0.00)[2a07:de40:b281:106:10:150:64:167:received]; DKIM_TRACE(0.00)[suse.de:+]; RCVD_VIA_SMTP_AUTH(0.00)[]; DBL_BLOCKED_OPENRESOLVER(0.00)[suse.de:dkim,suse.de:mid,imap1.dmz-prg2.suse.org:rdns,imap1.dmz-prg2.suse.org:helo] X-Spam-Score: -3.01 Hi Am 19.10.25 um 16:34 schrieb Greg KH: > On Sun, Oct 19, 2025 at 04:12:28PM +0100, Mehdi Ben Hadj Khelifa wrote: >> Replace kmalloc() with kmalloc_array() to correctly >> handle array allocations and benefit from built-in overflow checking[1]. >> >> [1]:https://docs.kernel.org/process/deprecated.html >> >> Signed-off-by: Mehdi Ben Hadj Khelifa >> --- >> drivers/gpu/drm/tiny/repaper.c | 2 +- >> 1 file changed, 1 insertion(+), 1 deletion(-) >> >> diff --git a/drivers/gpu/drm/tiny/repaper.c b/drivers/gpu/drm/tiny/repaper.c >> index 4824f863fdba..290132c24ff9 100644 >> --- a/drivers/gpu/drm/tiny/repaper.c >> +++ b/drivers/gpu/drm/tiny/repaper.c >> @@ -534,7 +534,7 @@ static int repaper_fb_dirty(struct drm_framebuffer *fb, const struct iosys_map * >> DRM_DEBUG("Flushing [FB:%d] st=%ums\n", fb->base.id, >> epd->factored_stage_time); >> >> - buf = kmalloc(fb->width * fb->height / 8, GFP_KERNEL); >> + buf = kmalloc_array(fb->height / 8, fb->width, GFP_KERNEL); > This isn't an array, so this function change doesn't seem to make much > sense, right? The size should have already been checked earlier in the > call change to be correct. Yes, we've recently received plenty of these pointless changes. The correct code would compute the number of bytes per pixel using drm_format_info_min_pitch() and multiply with fb->height. The latter could (maybe) use kmalloc_array(). It would still not be an array in the common sense. Best regards Thomas > > thanks, > > greg k-h -- -- 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)