dma-debug: fix return value of __setup handlers

When valid kernel command line parameters
  dma_debug=off dma_debug_entries=100
are used, they are reported as Unknown parameters and added to init's
environment strings, polluting it.

  Unknown kernel command line parameters "BOOT_IMAGE=/boot/bzImage-517rc5
    dma_debug=off dma_debug_entries=100", will be passed to user space.

and

 Run /sbin/init as init process
   with arguments:
     /sbin/init
   with environment:
     HOME=/
     TERM=linux
     BOOT_IMAGE=/boot/bzImage-517rc5
     dma_debug=off
     dma_debug_entries=100

Return 1 from these __setup handlers to indicate that the command line
option has been handled.

Fixes: 59d3daafa1726 ("dma-debug: add kernel command line parameters")
Signed-off-by: Randy Dunlap <[email protected]>
Reported-by: Igor Zhbanov <[email protected]>
Link: lore.kernel.org/r/[email protected]
Cc: Joerg Roedel <[email protected]>
Cc: Christoph Hellwig <[email protected]>
Cc: Marek Szyprowski <[email protected]>
Cc: [email protected]
Cc: Robin Murphy <[email protected]>
Signed-off-by: Christoph Hellwig <[email protected]>

1 files changed, 2 insertions, 2 deletions

diff --git a/kernel/dma/debug.c b/kernel/dma/debug.c
index 7a14ca29c377..f8ff598596b8 100644
--- a/kernel/dma/debug.c
+++ b/kernel/dma/debug.c
@@ -927,7 +927,7 @@ static __init int dma_debug_cmdline(char *str)
 		global_disable = true;
 	}
 
-	return 0;
+	return 1;
 }
 
 static __init int dma_debug_entries_cmdline(char *str)
@@ -936,7 +936,7 @@ static __init int dma_debug_entries_cmdline(char *str)
 		return -EINVAL;
 	if (!get_option(&str, &nr_prealloc_entries))
 		nr_prealloc_entries = PREALLOC_DMA_DEBUG_ENTRIES;
-	return 0;
+	return 1;
 }
 
 __setup("dma_debug=", dma_debug_cmdline);