From 09282b8a0b4b8ff7c57daf371dc3ea192e2947d3 Mon Sep 17 00:00:00 2001 From: "Darrick J. Wong" Date: Wed, 28 Jan 2015 08:53:54 -0500 Subject: [PATCH] e2fsck: decrement bad count _after_ remapping a duplicate block Decrement the bad count *after* we've shown that (a) we can allocate a replacement block and (b) remap the file block. Unfortunately, the only way to tell if the remapping succeeded is to wait until the next clone_file_block() call or block_iterate3() returns. Otherwise, there's a corruption error: we decrease the badcount once in preparation to remap, then the remap fails (either we can't find a replacement block or we have to split the extent tree and can't find a new extent block), so we delete the file, which decreases the badcount on the block a second time. Later on e2fsck will think that it's straightened out all the duplicate blocks, which isn't true. Signed-off-by: Darrick J. Wong Signed-off-by: Theodore Ts'o --- e2fsck/pass1b.c | 32 +++++++++++++++++++-- tests/f_cloneblock_alloc_error/expect.1 | 36 ++++++++++++++++++++++++ tests/f_cloneblock_alloc_error/expect.2 | 7 +++++ tests/f_cloneblock_alloc_error/image.gz | Bin 0 -> 3441 bytes tests/f_cloneblock_alloc_error/name | 1 + 5 files changed, 73 insertions(+), 3 deletions(-) create mode 100644 tests/f_cloneblock_alloc_error/expect.1 create mode 100644 tests/f_cloneblock_alloc_error/expect.2 create mode 100644 tests/f_cloneblock_alloc_error/image.gz create mode 100644 tests/f_cloneblock_alloc_error/name diff --git a/e2fsck/pass1b.c b/e2fsck/pass1b.c index 2d1b448b..cd967f4b 100644 --- a/e2fsck/pass1b.c +++ b/e2fsck/pass1b.c @@ -725,8 +725,30 @@ struct clone_struct { char *buf; e2fsck_t ctx; struct ext2_inode *inode; + + struct dup_cluster *save_dup_cluster; + blk64_t save_blocknr; }; +/* + * Decrement the bad count *after* we've shown that (a) we can allocate a + * replacement block and (b) remap the file blocks. Unfortunately, there's no + * way to find out if the remap succeeded until either the next + * clone_file_block() call (an error when remapping the block after returning + * BLOCK_CHANGED will halt the iteration) or after block_iterate() returns. + * Otherwise, it's possible that we decrease the badcount once in preparation + * to remap, then the remap fails (either we can't find a replacement block or + * we have to split the extent tree and can't find a new extent block), so we + * delete the file, which decreases the badcount again. + */ +static void deferred_dec_badcount(struct clone_struct *cs) +{ + if (!cs->save_dup_cluster) + return; + decrement_badcount(cs->ctx, cs->save_blocknr, cs->save_dup_cluster); + cs->save_dup_cluster = NULL; +} + static int clone_file_block(ext2_filsys fs, blk64_t *block_nr, e2_blkcnt_t blockcnt, @@ -734,7 +756,7 @@ static int clone_file_block(ext2_filsys fs, int ref_offset EXT2FS_ATTR((unused)), void *priv_data) { - struct dup_cluster *p; + struct dup_cluster *p = NULL; blk64_t new_block; errcode_t retval; struct clone_struct *cs = (struct clone_struct *) priv_data; @@ -744,6 +766,7 @@ static int clone_file_block(ext2_filsys fs, int is_meta = 0; ctx = cs->ctx; + deferred_dec_badcount(cs); if (HOLE_BLKADDR(*block_nr)) return 0; @@ -768,8 +791,6 @@ static int clone_file_block(ext2_filsys fs, } p = (struct dup_cluster *) dnode_get(n); - if (!is_meta) - decrement_badcount(ctx, *block_nr, p); cs->dup_cluster = c; /* @@ -819,6 +840,8 @@ cluster_alloc_ok: cs->errcode = retval; return BLOCK_ABORT; } + cs->save_dup_cluster = (is_meta ? NULL : p); + cs->save_blocknr = *block_nr; *block_nr = new_block; ext2fs_mark_block_bitmap2(ctx->block_found_map, new_block); ext2fs_mark_block_bitmap2(fs->block_map, new_block); @@ -848,6 +871,8 @@ static errcode_t clone_file(e2fsck_t ctx, ext2_ino_t ino, cs.ctx = ctx; cs.ino = ino; cs.inode = &dp->inode; + cs.save_dup_cluster = NULL; + cs.save_blocknr = 0; retval = ext2fs_get_mem(fs->blocksize, &cs.buf); if (retval) return retval; @@ -860,6 +885,7 @@ static errcode_t clone_file(e2fsck_t ctx, ext2_ino_t ino, if (ext2fs_inode_has_valid_blocks2(fs, &dp->inode)) pctx.errcode = ext2fs_block_iterate3(fs, ino, 0, block_buf, clone_file_block, &cs); + deferred_dec_badcount(&cs); ext2fs_mark_bb_dirty(fs); if (pctx.errcode) { fix_problem(ctx, PR_1B_BLOCK_ITERATE, &pctx); diff --git a/tests/f_cloneblock_alloc_error/expect.1 b/tests/f_cloneblock_alloc_error/expect.1 new file mode 100644 index 00000000..24fe1ff4 --- /dev/null +++ b/tests/f_cloneblock_alloc_error/expect.1 @@ -0,0 +1,36 @@ +Pass 1: Checking inodes, blocks, and sizes +Inode 12, i_size is 0, should be 2015232. Fix? yes + + +Running additional passes to resolve blocks claimed by more than one inode... +Pass 1B: Rescanning for multiply-claimed blocks +Multiply-claimed block(s) in inode 13: 8 +Multiply-claimed block(s) in inode 14: 8 +Pass 1C: Scanning directories for inodes with multiply-claimed blocks +Pass 1D: Reconciling multiply-claimed blocks +(There are 2 inodes containing multiply-claimed blocks.) + +File /b (inode #13, mod time Wed Jan 21 03:41:55 2015) + has 1 multiply-claimed block(s), shared with 1 file(s): + /c (inode #14, mod time Wed Jan 21 03:42:37 2015) +Clone multiply-claimed blocks? yes + +clone_file: Could not allocate block in ext2 filesystem returned from clone_file_block +Couldn't clone file: Could not allocate block in ext2 filesystem +Delete file? yes + +File /c (inode #14, mod time Wed Jan 21 03:42:37 2015) + has 1 multiply-claimed block(s), shared with 1 file(s): + /b (inode #13, mod time Wed Jan 21 03:41:55 2015) +Multiply-claimed blocks already reassigned or cloned. + +Pass 2: Checking directory structure +Entry 'b' in / (2) has deleted/unused inode 13. Clear? yes + +Pass 3: Checking directory connectivity +Pass 4: Checking reference counts +Pass 5: Checking group summary information + +test_filesys: ***** FILE SYSTEM WAS MODIFIED ***** +test_filesys: 13/128 files (7.7% non-contiguous), 512/512 blocks +Exit status is 1 diff --git a/tests/f_cloneblock_alloc_error/expect.2 b/tests/f_cloneblock_alloc_error/expect.2 new file mode 100644 index 00000000..f7781ec2 --- /dev/null +++ b/tests/f_cloneblock_alloc_error/expect.2 @@ -0,0 +1,7 @@ +Pass 1: Checking inodes, blocks, and sizes +Pass 2: Checking directory structure +Pass 3: Checking directory connectivity +Pass 4: Checking reference counts +Pass 5: Checking group summary information +test_filesys: 13/128 files (7.7% non-contiguous), 512/512 blocks +Exit status is 0 diff --git a/tests/f_cloneblock_alloc_error/image.gz b/tests/f_cloneblock_alloc_error/image.gz new file mode 100644 index 0000000000000000000000000000000000000000..ed01df1b9fb7a10f49338cd994ca4ef4cf646bba GIT binary patch literal 3441 zcmeH{X;4#l5Ws^6bgBfaRi{$GYNyn(k~#_sX`qVASmjU*F@X>Ulq2EL(wE?)AyO;e zF!hQDhoC}|mjpG22$)2xLXiqZ-%$cVl<|7cc;O%FQ}T+_Z~fFS{l zu|Ab!m*;jyFj&GV@$|&~gb^v5LKol8@%`PmJIEBc;8^I_=L%lN5N!7323zL+ z7xdH}bK4iroqwk!@3e2I{(&bqPkv{=DI*)c`Cz8O(tfc`-8((ax#^{rTPl)K!oVtf z*Cp@PY}>;Zom_cl8)OM+Rki;d?x`Le;gh|5-Y|=`@nuP!UB>S0j7n!BEw^ISm6O&U zqx{FQSlb!pK95mzr0>ODrjS}Gg`tmM?tGFxD^yt&2idW(JY)4-G zJu0_HzNPHwz$#lM_C07ydDq`xnH=-JMf2H(?d8nfrA2LTB3LZexr4%M;!(@$U`C^? zN6e_Y;_S{;y!ZZ#%rCwXD@ykpP2KpUVB&;-l{|xo5lCijQblXL(DAa=XdR$F3U2fl z#!IC`d>RPH0TUe8#wH!Z7{f`Z%?e_ zqVZG~cnz=OnJW2QJSNyAH)as|WFxo?7rEARG&6CdInk9|i0U1tA)QrL1+Q}@a*S$p zjZALU44K8{B!TE2P#UJ~6F%1|h(gi|Y_O^#sSfobcYx|Ja}08a+8<`> z(D@KiPBl3p0p1vOLVvfy5GTz;QZTX$;bI5>RjUaR$o1fkDxrV(kwM3 z4C}grYg_P3B5MmV3wkax;W{%FZjNzUo(U)%hL{s^J{m9l`iTt`;R#N`TX<*uMLvi( zbr0-5kyNIi7i{+D`(iENvEz(?{7F2G+8S)|mz>0=NeAK7oOQ9fC+5vL{6yjqHP0NK zlh}g|1)r8{>hL?{6R;mn=OJ=^g*4rj)M=7%ilfz#Y~YqxC_(s7Od! zkx)l`0;N~*1B_*86qN>E(kqk~I*hScD3n_vs4@;xi$FJ>B#x`9pCnthK);W?PcIj* zm*_c|nwk%=ri-=&Nqsx%3vST~%I2W@=cs}z1S9ma1-bydjBEvm=&TWaQLDNA@;$`JDR`_#~a zk-