Patchwork [U-Boot,13/17] mmc: Fix incorrect handling of 'read' & 'write' commands

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Submitter Simon Glass
Date Nov. 3, 2012, 12:27 a.m.
Message ID <1351902453-27956-14-git-send-email-sjg@chromium.org>
Download mbox | patch
Permalink /patch/196788/
State Superseded, archived
Delegated to: Tom Rini
Headers show

Comments

Simon Glass - Nov. 3, 2012, 12:27 a.m.
From: Taylor Hutt <thutt@chromium.org>

If a malformed 'read' or 'write' command is issued, the Sandbox U-Boot
can crash because the command-handling code does no error checking on
the number of provided arguments.

This change makes the mmc 'erase', 'read' and 'write' commands only
function if the proper number of arguments are supplied.

Also puts the else assignment at the beginning fo the if() statement
to shortens the generated code.  This removes an unnecessary jump from
the generated code.

BRANCH=none
Signed-off-by: Taylor Hutt <thutt@chromium.org>
Signed-off-by: Simon Glass <sjg@chromium.org>
---
 common/cmd_mmc.c |    9 ++++-----
 1 files changed, 4 insertions(+), 5 deletions(-)

Patch

diff --git a/common/cmd_mmc.c b/common/cmd_mmc.c
index 79a1088..735947b 100644
--- a/common/cmd_mmc.c
+++ b/common/cmd_mmc.c
@@ -250,14 +250,13 @@  int do_mmcops(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
 		return 0;
 	}
 
-	if (strcmp(argv[1], "read") == 0)
+	state = MMC_INVALID;
+	if (argc == 5 && strcmp(argv[1], "read") == 0)
 		state = MMC_READ;
-	else if (strcmp(argv[1], "write") == 0)
+	else if (argc == 5 && strcmp(argv[1], "write") == 0)
 		state = MMC_WRITE;
-	else if (strcmp(argv[1], "erase") == 0)
+	else if (argc == 4 && strcmp(argv[1], "erase") == 0)
 		state = MMC_ERASE;
-	else
-		state = MMC_INVALID;
 
 	if (state != MMC_INVALID) {
 		struct mmc *mmc = find_mmc_device(curr_device);