From: Eugen Hristev Date: Wed, 9 May 2018 13:28:37 +0000 (+0300) Subject: fs: ext4: fix crash on ext4ls X-Git-Tag: v2018.07-rc1~111 X-Git-Url: https://git.sur5r.net/?p=u-boot;a=commitdiff_plain;h=e71a969cea56eb3e93de3320df5ce44c9e4e1c53 fs: ext4: fix crash on ext4ls Found a crash while issuing ext4ls with a non-existent directory. Crash test: => ext4ls mmc 0 1 ** Can not find directory. ** data abort pc : [<3fd7c2ec>] lr : [<3fd93ed8>] reloc pc : [<26f142ec>] lr : [<26f2bed8>] sp : 3f963338 ip : 3fdc3dc4 fp : 3fd6b370 r10: 00000004 r9 : 3f967ec0 r8 : 3f96db68 r7 : 3fdc99b4 r6 : 00000000 r5 : 3f96dc88 r4 : 3fdcbc8c r3 : fffffffa r2 : 00000000 r1 : 3f96e0bc r0 : 00000002 Flags: nZCv IRQs off FIQs off Mode SVC_32 Resetting CPU ... resetting ... Tested on SAMA5D2_Xplained board (sama5d2_xplained_mmc_defconfig) Looks like crash is introduced by commit: "fa9ca8a" fs/ext4/ext4fs.c: Free dirnode in error path of ext4fs_ls Issue is that dirnode is not initialized, and then freed if the call to ext4_ls fails. ext4_ls will not change the value of dirnode in this case thus we have a crash with data abort. I added initialization and a check for dirname being NULL. Fixes: "fa9ca8a" fs/ext4/ext4fs.c: Free dirnode in error path of ext4fs_ls Cc: Stefan Brüns Cc: Tom Rini Signed-off-by: Eugen Hristev Reviewed-by: Tom Rini --- diff --git a/fs/ext4/ext4fs.c b/fs/ext4/ext4fs.c index 4b36a3e608..2a28031d14 100644 --- a/fs/ext4/ext4fs.c +++ b/fs/ext4/ext4fs.c @@ -164,7 +164,7 @@ int ext4fs_read_file(struct ext2fs_node *node, loff_t pos, int ext4fs_ls(const char *dirname) { - struct ext2fs_node *dirnode; + struct ext2fs_node *dirnode = NULL; int status; if (dirname == NULL) @@ -174,7 +174,8 @@ int ext4fs_ls(const char *dirname) FILETYPE_DIRECTORY); if (status != 1) { printf("** Can not find directory. **\n"); - ext4fs_free_node(dirnode, &ext4fs_root->diropen); + if (dirnode) + ext4fs_free_node(dirnode, &ext4fs_root->diropen); return 1; }