From: James Simmons Date: Mon, 22 Aug 2016 16:57:43 +0000 (-0400) Subject: staging: lustre: mdc: fix NULL pointer dereference in mdc_adjust_dirpages X-Git-Tag: v4.9-rc1~119^2~900 X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=88b090e3c020bfeac13d5c52984a03775808cb67;p=karo-tx-linux.git staging: lustre: mdc: fix NULL pointer dereference in mdc_adjust_dirpages The function mdc_adjust_dirpages is only called on platforms which don't have pages 4K in size which is why kbuild only reported this for platforms like the Alpha. The problem was a typo in ordering of variables in the beginning of a while loop. We were accessing the dp pointer before it was kmapped. Signed-off-by: James Simmons Reviewed-by: Andreas Dilger Signed-off-by: Greg Kroah-Hartman --- diff --git a/drivers/staging/lustre/lustre/mdc/mdc_request.c b/drivers/staging/lustre/lustre/mdc/mdc_request.c index 88848d8d2fe0..7a182be6d6df 100644 --- a/drivers/staging/lustre/lustre/mdc/mdc_request.c +++ b/drivers/staging/lustre/lustre/mdc/mdc_request.c @@ -1133,9 +1133,9 @@ static void mdc_adjust_dirpages(struct page **pages, int cfs_pgs, int lu_pgs) int i; for (i = 0; i < cfs_pgs; i++) { + struct lu_dirpage *dp = kmap(pages[i]); __u64 hash_end = le64_to_cpu(dp->ldp_hash_end); __u32 flags = le32_to_cpu(dp->ldp_flags); - struct lu_dirpage *dp = kmap(pages[i]); struct lu_dirpage *first = dp; struct lu_dirent *end_dirent = NULL; struct lu_dirent *ent;