Patrick Palka 000a7d66ec kernel/printk/printk.c: fix faulty logic in the case of recursive printk ... We shouldn't set text_len in the code path that detects printk recursion because text_len corresponds to the length of the string inside textbuf. A few lines down from the line text_len = strlen(recursion_msg); is the line text_len += vscnprintf(text + text_len, ...); So if printk detects recursion, it sets text_len to 29 (the length of recursion_msg) and logs an error. Then the message supplied by the caller of printk is stored inside textbuf but offset by 29 bytes. This means that the output of the recursive call to printk will contain 29 bytes of garbage in front of it. This defect is caused by commit 458df9fd48 ("printk: remove separate printk_sched buffers and use printk buf instead") which turned the line text_len = vscnprintf(text, ...); into text_len += vscnprintf(text + text_len, ...); To fix this, this patch avoids setting text_len when logging the printk recursion error. This patch also marks unlikely() the branch leading up to this code. Fixes: 458df9fd48 ("printk: remove separate printk_sched buffers and use printk buf instead") Signed-off-by: Patrick Palka <patrick@parcs.ath.cx> Reviewed-by: Petr Mladek <pmladek@suse.cz> Reviewed-by: Jan Kara <jack@suse.cz> Acked-by: Steven Rostedt <rostedt@goodmis.org> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>		2014-09-10 15:42:12 -07:00
..
braille.c	printk: Fix return of braille_register_console()	2013-08-06 13:18:12 -07:00
braille.h	printk: move braille console support into separate braille.[ch] files	2013-07-31 14:41:03 -07:00
console_cmdline.h	printk: add console_cmdline.h	2013-07-31 14:41:03 -07:00
Makefile	printk: move braille console support into separate braille.[ch] files	2013-07-31 14:41:03 -07:00
printk.c	kernel/printk/printk.c: fix faulty logic in the case of recursive printk	2014-09-10 15:42:12 -07:00