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charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit X-Spamd-Result: default: False [-4.51 / 50.00]; BAYES_HAM(-3.00)[100.00%]; NEURAL_HAM_LONG(-1.00)[-1.000]; R_DKIM_ALLOW(-0.20)[suse.de:s=susede2_rsa,suse.de:s=susede2_ed25519]; NEURAL_HAM_SHORT(-0.20)[-1.000]; MIME_GOOD(-0.10)[text/plain]; MX_GOOD(-0.01)[]; FREEMAIL_TO(0.00)[huawei.com,ffwll.ch,gmx.de,vger.kernel.org]; FUZZY_RATELIMITED(0.00)[rspamd.com]; ARC_NA(0.00)[]; RCVD_VIA_SMTP_AUTH(0.00)[]; TO_DN_SOME(0.00)[]; MIME_TRACE(0.00)[0:+]; FREEMAIL_ENVRCPT(0.00)[gmx.de]; MID_RHS_MATCH_FROM(0.00)[]; DKIM_SIGNED(0.00)[suse.de:s=susede2_rsa,suse.de:s=susede2_ed25519]; FROM_EQ_ENVFROM(0.00)[]; FROM_HAS_DN(0.00)[]; RCPT_COUNT_FIVE(0.00)[6]; RCVD_TLS_ALL(0.00)[]; DBL_BLOCKED_OPENRESOLVER(0.00)[suse.com:url,suse.de:dkim,suse.de:mid,imap1.dmz-prg2.suse.org:helo,imap1.dmz-prg2.suse.org:rdns]; RCVD_COUNT_TWO(0.00)[2]; TO_MATCH_ENVRCPT_ALL(0.00)[]; DKIM_TRACE(0.00)[suse.de:+] X-Rspamd-Action: no action X-Spam-Flag: NO X-Spam-Score: -4.51 X-Spam-Level: X-Rspamd-Server: rspamd1.dmz-prg2.suse.org X-Rspamd-Queue-Id: 80F884DEF0 Hi, thanks for the patch. Am 27.02.26 um 15:43 schrieb Chen Jun: > When a font is set on an invisible console, the screen will not update. > However, the fontbuffer is not updated to match the new font dimensions. I looked through vc_resize() but cannot quite find the logic that calls fbcon_rotate_font(). Can you please point to correct place? Best regards Thomas > > This inconsistency leads to out-of-bounds memory access when writing to > the tty bound to fbcon, as demonstrated by the following KASAN report: > > BUG: KASAN: slab-out-of-bounds in fb_pad_aligned_buffer+0xdf/0x140 > Read of size 1 at addr ffff8881195a2280 by task a.out/971 > Call Trace: > > fb_pad_aligned_buffer+0xdf/0x140 > ud_putcs+0x88a/0xde0 > fbcon_putcs+0x319/0x430 > do_update_region+0x23c/0x3b0 > do_con_write+0x225c/0x67f0 > con_write+0xe/0x30 > n_tty_write+0x4b5/0xff0 > file_tty_write.isra.41+0x46c/0x880 > vfs_write+0x868/0xd60 > ksys_write+0xf2/0x1d0 > do_syscall_64+0xfa/0x570 > > Fix this by calling fbcon_rotate_font() if vc is invisible in > fbcon_do_set_font(). > > Signed-off-by: Chen Jun > --- > drivers/video/fbdev/core/fbcon.c | 5 +++++ > 1 file changed, 5 insertions(+) > > diff --git a/drivers/video/fbdev/core/fbcon.c b/drivers/video/fbdev/core/fbcon.c > index 666261ae59d8..d76100188bee 100644 > --- a/drivers/video/fbdev/core/fbcon.c > +++ b/drivers/video/fbdev/core/fbcon.c > @@ -2444,6 +2444,11 @@ static int fbcon_do_set_font(struct vc_data *vc, int w, int h, int charcount, > rows = FBCON_SWAP(par->rotate, info->var.yres, info->var.xres); > cols /= w; > rows /= h; > + if (!con_is_visible(vc)) { > + ret = fbcon_rotate_font(info, vc); > + if (ret) > + goto err_out; > + } > ret = vc_resize(vc, cols, rows); > if (ret) > goto err_out; -- -- 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)