Some DVDs are failing to mount with the error: [ 632.305370] UDF-fs: warning (device loop0): udf_load_vrs: No anchor found [ 632.305372] UDF-fs: Scanning with blocksize 512 failed [ 632.307837] UDF-fs: warning (device loop0): udf_load_vrs: No anchor found [ 632.307839] UDF-fs: Scanning with blocksize 1024 failed [ 632.309320] UDF-fs: incorrect dstring lengths (32/32) [ 632.309361] UDF-fs: Scanning with blocksize 2048 failed [ 632.309530] UDF-fs: warning (device loop0): udf_load_vrs: No VRS found [ 632.309531] UDF-fs: Scanning with blocksize 4096 failed
This particular DVD used to work with v4.4 kernels, and has stopped working after updating the kernel to v4.14. Did a git bisect and that pointed to: c26f6c615788 ("udf: Fix conversion of 'dstring' fields to UTF8") This patch effectively reverts c26f6c615788 and removes the length check that it introduced. And after this patch: [ 61.767204] UDF-fs: warning (device loop0): udf_load_vrs: No anchor found [ 61.767206] UDF-fs: Scanning with blocksize 512 failed [ 61.770011] UDF-fs: warning (device loop0): udf_load_vrs: No anchor found [ 61.770026] UDF-fs: Scanning with blocksize 1024 failed [ 61.773006] UDF-fs: warning (device loop0): udf_load_vrs: No anchor found [ 61.773007] UDF-fs: Scanning with blocksize 512 failed [ 61.774401] UDF-fs: warning (device loop0): udf_load_vrs: No anchor found [ 61.774402] UDF-fs: Scanning with blocksize 1024 failed [ 61.775045] UDF-fs: INFO Mounting volume 'TOUR_2017_THANKSGIVING_25_DISC ', timestamp 2018/01/30 05:57 (1000) The DVD is available at: https://www.amazon.co.jp/Live-%E3%80%8CMr-Children-DOME-STADIUM-Thanksgiving/dp/B079B5W6KC Cc: Andrew Gabbasov <andrew_gabba...@mentor.com> Signed-off-by: Sudip Mukherjee <sudipm.mukher...@gmail.com> --- I dont't think this is the correct fix but has solved the problem for now. I have the iso image of the DVD for testing, and if there is a better solution I can test. fs/udf/unicode.c | 8 +------- 1 file changed, 1 insertion(+), 7 deletions(-) diff --git a/fs/udf/unicode.c b/fs/udf/unicode.c index 45234791fec2..9f80c56178a5 100644 --- a/fs/udf/unicode.c +++ b/fs/udf/unicode.c @@ -356,14 +356,8 @@ int udf_dstrCS0toChar(struct super_block *sb, uint8_t *utf_o, int o_len, { int s_len = 0; - if (i_len > 0) { + if (i_len > 0) s_len = ocu_i[i_len - 1]; - if (s_len >= i_len) { - pr_err("incorrect dstring lengths (%d/%d)\n", - s_len, i_len); - return -EINVAL; - } - } return udf_name_from_CS0(sb, utf_o, o_len, ocu_i, s_len, 0); } -- 2.11.0