From 0304688676bdfc8159e165313d71da19c118ba27 Mon Sep 17 00:00:00 2001 From: "vikram.jadhav07" Date: Sun, 13 Mar 2016 17:56:52 -0400 Subject: ext4: clean up error handling in the MMP support There is memory leak as both caller function kmmpd() and callee read_mmp_block() not releasing bh_check (i.e buffer_head). Given patch fixes this problem. [ Additional changes suggested by Andreas Dilger -- TYT ] Signed-off-by: Jadhav Vikram Signed-off-by: Theodore Ts'o --- fs/ext4/mmp.c | 34 +++++++++++++++++----------------- 1 file changed, 17 insertions(+), 17 deletions(-) (limited to 'fs/ext4/mmp.c') diff --git a/fs/ext4/mmp.c b/fs/ext4/mmp.c index 0a512aa81bf7..24445275d330 100644 --- a/fs/ext4/mmp.c +++ b/fs/ext4/mmp.c @@ -91,21 +91,22 @@ static int read_mmp_block(struct super_block *sb, struct buffer_head **bh, submit_bh(READ_SYNC | REQ_META | REQ_PRIO, *bh); wait_on_buffer(*bh); if (!buffer_uptodate(*bh)) { - brelse(*bh); - *bh = NULL; ret = -EIO; goto warn_exit; } - mmp = (struct mmp_struct *)((*bh)->b_data); - if (le32_to_cpu(mmp->mmp_magic) != EXT4_MMP_MAGIC) + if (le32_to_cpu(mmp->mmp_magic) != EXT4_MMP_MAGIC) { ret = -EFSCORRUPTED; - else if (!ext4_mmp_csum_verify(sb, mmp)) + goto warn_exit; + } + if (!ext4_mmp_csum_verify(sb, mmp)) { ret = -EFSBADCRC; - else - return 0; - + goto warn_exit; + } + return 0; warn_exit: + brelse(*bh); + *bh = NULL; ext4_warning(sb, "Error %d while reading MMP block %llu", ret, mmp_block); return ret; @@ -181,15 +182,13 @@ static int kmmpd(void *data) EXT4_FEATURE_INCOMPAT_MMP)) { ext4_warning(sb, "kmmpd being stopped since MMP feature" " has been disabled."); - EXT4_SB(sb)->s_mmp_tsk = NULL; - goto failed; + goto exit_thread; } if (sb->s_flags & MS_RDONLY) { ext4_warning(sb, "kmmpd being stopped since filesystem " "has been remounted as readonly."); - EXT4_SB(sb)->s_mmp_tsk = NULL; - goto failed; + goto exit_thread; } diff = jiffies - last_update_time; @@ -211,9 +210,7 @@ static int kmmpd(void *data) if (retval) { ext4_error(sb, "error reading MMP data: %d", retval); - - EXT4_SB(sb)->s_mmp_tsk = NULL; - goto failed; + goto exit_thread; } mmp_check = (struct mmp_struct *)(bh_check->b_data); @@ -225,7 +222,9 @@ static int kmmpd(void *data) "The filesystem seems to have been" " multiply mounted."); ext4_error(sb, "abort"); - goto failed; + put_bh(bh_check); + retval = -EBUSY; + goto exit_thread; } put_bh(bh_check); } @@ -248,7 +247,8 @@ static int kmmpd(void *data) retval = write_mmp_block(sb, bh); -failed: +exit_thread: + EXT4_SB(sb)->s_mmp_tsk = NULL; kfree(data); brelse(bh); return retval; -- cgit v1.2.3