From d1ca8698ca1332625d83ea0d753747be66f9906d Mon Sep 17 00:00:00 2001 From: Al Viro Date: Sat, 8 Mar 2025 19:26:31 -0500 Subject: [PATCH 1/5] spufs: fix a leak on spufs_new_file() failure It's called from spufs_fill_dir(), and caller of that will do spufs_rmdir() in case of failure. That does remove everything we'd managed to create, but... the problem dentry is still negative. IOW, it needs to be explicitly dropped. Fixes: 3f51dd91c807 "[PATCH] spufs: fix spufs_fill_dir error path" Signed-off-by: Al Viro --- arch/powerpc/platforms/cell/spufs/inode.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/arch/powerpc/platforms/cell/spufs/inode.c b/arch/powerpc/platforms/cell/spufs/inode.c index 70236d1df3d3e..793c005607cf0 100644 --- a/arch/powerpc/platforms/cell/spufs/inode.c +++ b/arch/powerpc/platforms/cell/spufs/inode.c @@ -192,8 +192,10 @@ static int spufs_fill_dir(struct dentry *dir, return -ENOMEM; ret = spufs_new_file(dir->d_sb, dentry, files->ops, files->mode & mode, files->size, ctx); - if (ret) + if (ret) { + dput(dentry); return ret; + } files++; } return 0; From c134deabf4784e155d360744d4a6a835b9de4dd4 Mon Sep 17 00:00:00 2001 From: Al Viro Date: Wed, 12 Mar 2025 19:18:39 -0400 Subject: [PATCH 2/5] spufs: fix gang directory lifetimes prior to "[POWERPC] spufs: Fix gang destroy leaks" we used to have a problem with gang lifetimes - creation of a gang returns opened gang directory, which normally gets removed when that gets closed, but if somebody has created a context belonging to that gang and kept it alive until the gang got closed, removal failed and we ended up with a leak. Unfortunately, it had been fixed the wrong way. Dentry of gang directory was no longer pinned, and rmdir on close was gone. One problem was that failure of open kept calling simple_rmdir() as cleanup, which meant an unbalanced dput(). Another bug was in the success case - gang creation incremented link count on root directory, but that was no longer undone when gang got destroyed. Fix consists of * reverting the commit in question * adding a counter to gang, protected by ->i_rwsem of gang directory inode. * having it set to 1 at creation time, dropped in both spufs_dir_close() and spufs_gang_close() and bumped in spufs_create_context(), provided that it's not 0. * using simple_recursive_removal() to take the gang directory out when counter reaches zero. Fixes: 877907d37da9 "[POWERPC] spufs: Fix gang destroy leaks" Signed-off-by: Al Viro --- arch/powerpc/platforms/cell/spufs/gang.c | 1 + arch/powerpc/platforms/cell/spufs/inode.c | 54 +++++++++++++++++++---- arch/powerpc/platforms/cell/spufs/spufs.h | 2 + 3 files changed, 49 insertions(+), 8 deletions(-) diff --git a/arch/powerpc/platforms/cell/spufs/gang.c b/arch/powerpc/platforms/cell/spufs/gang.c index 827d338deaf4c..2c2999de6bfa2 100644 --- a/arch/powerpc/platforms/cell/spufs/gang.c +++ b/arch/powerpc/platforms/cell/spufs/gang.c @@ -25,6 +25,7 @@ struct spu_gang *alloc_spu_gang(void) mutex_init(&gang->aff_mutex); INIT_LIST_HEAD(&gang->list); INIT_LIST_HEAD(&gang->aff_list_head); + gang->alive = 1; out: return gang; diff --git a/arch/powerpc/platforms/cell/spufs/inode.c b/arch/powerpc/platforms/cell/spufs/inode.c index 793c005607cf0..c566e7997f2c1 100644 --- a/arch/powerpc/platforms/cell/spufs/inode.c +++ b/arch/powerpc/platforms/cell/spufs/inode.c @@ -201,6 +201,23 @@ static int spufs_fill_dir(struct dentry *dir, return 0; } +static void unuse_gang(struct dentry *dir) +{ + struct inode *inode = dir->d_inode; + struct spu_gang *gang = SPUFS_I(inode)->i_gang; + + if (gang) { + bool dead; + + inode_lock(inode); // exclusion with spufs_create_context() + dead = !--gang->alive; + inode_unlock(inode); + + if (dead) + simple_recursive_removal(dir, NULL); + } +} + static int spufs_dir_close(struct inode *inode, struct file *file) { struct inode *parent; @@ -215,6 +232,7 @@ static int spufs_dir_close(struct inode *inode, struct file *file) inode_unlock(parent); WARN_ON(ret); + unuse_gang(dir->d_parent); return dcache_dir_close(inode, file); } @@ -407,7 +425,7 @@ spufs_create_context(struct inode *inode, struct dentry *dentry, { int ret; int affinity; - struct spu_gang *gang; + struct spu_gang *gang = SPUFS_I(inode)->i_gang; struct spu_context *neighbor; struct path path = {.mnt = mnt, .dentry = dentry}; @@ -422,11 +440,15 @@ spufs_create_context(struct inode *inode, struct dentry *dentry, if ((flags & SPU_CREATE_ISOLATE) && !isolated_loader) return -ENODEV; - gang = NULL; + if (gang) { + if (!gang->alive) + return -ENOENT; + gang->alive++; + } + neighbor = NULL; affinity = flags & (SPU_CREATE_AFFINITY_MEM | SPU_CREATE_AFFINITY_SPU); if (affinity) { - gang = SPUFS_I(inode)->i_gang; if (!gang) return -EINVAL; mutex_lock(&gang->aff_mutex); @@ -455,6 +477,8 @@ spufs_create_context(struct inode *inode, struct dentry *dentry, out_aff_unlock: if (affinity) mutex_unlock(&gang->aff_mutex); + if (ret && gang) + gang->alive--; // can't reach 0 return ret; } @@ -484,6 +508,7 @@ spufs_mkgang(struct inode *dir, struct dentry *dentry, umode_t mode) inode->i_fop = &simple_dir_operations; d_instantiate(dentry, inode); + dget(dentry); inc_nlink(dir); inc_nlink(d_inode(dentry)); return ret; @@ -494,6 +519,21 @@ spufs_mkgang(struct inode *dir, struct dentry *dentry, umode_t mode) return ret; } +static int spufs_gang_close(struct inode *inode, struct file *file) +{ + unuse_gang(file->f_path.dentry); + return dcache_dir_close(inode, file); +} + +static const struct file_operations spufs_gang_fops = { + .open = dcache_dir_open, + .release = spufs_gang_close, + .llseek = dcache_dir_lseek, + .read = generic_read_dir, + .iterate_shared = dcache_readdir, + .fsync = noop_fsync, +}; + static int spufs_gang_open(const struct path *path) { int ret; @@ -513,7 +553,7 @@ static int spufs_gang_open(const struct path *path) return PTR_ERR(filp); } - filp->f_op = &simple_dir_operations; + filp->f_op = &spufs_gang_fops; fd_install(ret, filp); return ret; } @@ -528,10 +568,8 @@ static int spufs_create_gang(struct inode *inode, ret = spufs_mkgang(inode, dentry, mode & 0777); if (!ret) { ret = spufs_gang_open(&path); - if (ret < 0) { - int err = simple_rmdir(inode, dentry); - WARN_ON(err); - } + if (ret < 0) + unuse_gang(dentry); } return ret; } diff --git a/arch/powerpc/platforms/cell/spufs/spufs.h b/arch/powerpc/platforms/cell/spufs/spufs.h index 84958487f696a..d33787c57c39a 100644 --- a/arch/powerpc/platforms/cell/spufs/spufs.h +++ b/arch/powerpc/platforms/cell/spufs/spufs.h @@ -151,6 +151,8 @@ struct spu_gang { int aff_flags; struct spu *aff_ref_spu; atomic_t aff_sched_count; + + int alive; }; /* Flag bits for spu_gang aff_flags */ From 0f5cce3fc55b08ee4da3372baccf4bcd36a98396 Mon Sep 17 00:00:00 2001 From: Al Viro Date: Wed, 12 Mar 2025 19:38:28 -0400 Subject: [PATCH 3/5] spufs: fix a leak in spufs_create_context() Leak fixes back in 2008 missed one case - if we are trying to set affinity and spufs_mkdir() fails, we need to drop the reference to neighbor. Fixes: 58119068cb27 "[POWERPC] spufs: Fix memory leak on SPU affinity" Signed-off-by: Al Viro --- arch/powerpc/platforms/cell/spufs/inode.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/arch/powerpc/platforms/cell/spufs/inode.c b/arch/powerpc/platforms/cell/spufs/inode.c index c566e7997f2c1..9f9e4b8716278 100644 --- a/arch/powerpc/platforms/cell/spufs/inode.c +++ b/arch/powerpc/platforms/cell/spufs/inode.c @@ -460,8 +460,11 @@ spufs_create_context(struct inode *inode, struct dentry *dentry, } ret = spufs_mkdir(inode, dentry, flags, mode & 0777); - if (ret) + if (ret) { + if (neighbor) + put_spu_context(neighbor); goto out_aff_unlock; + } if (affinity) { spufs_set_affinity(flags, SPUFS_I(d_inode(dentry))->i_ctx, From bdb43af4fdb39f844ede401bdb1258f67a580a27 Mon Sep 17 00:00:00 2001 From: Al Viro Date: Mon, 13 May 2024 17:50:34 -0600 Subject: [PATCH 4/5] qibfs: fix _another_ leak failure to allocate inode => leaked dentry... this one had been there since the initial merge; to be fair, if we are that far OOM, the odds of failing at that particular allocation are low... Signed-off-by: Al Viro --- drivers/infiniband/hw/qib/qib_fs.c | 1 + 1 file changed, 1 insertion(+) diff --git a/drivers/infiniband/hw/qib/qib_fs.c b/drivers/infiniband/hw/qib/qib_fs.c index b27791029fa93..b9f4a2937c3ac 100644 --- a/drivers/infiniband/hw/qib/qib_fs.c +++ b/drivers/infiniband/hw/qib/qib_fs.c @@ -55,6 +55,7 @@ static int qibfs_mknod(struct inode *dir, struct dentry *dentry, struct inode *inode = new_inode(dir->i_sb); if (!inode) { + dput(dentry); error = -EPERM; goto bail; } From 00cdfdcfa0806202aea56b02cedbf87ef1e75df8 Mon Sep 17 00:00:00 2001 From: Al Viro Date: Mon, 17 Mar 2025 22:06:04 -0400 Subject: [PATCH 5/5] hypfs_create_cpu_files(): add missing check for hypfs_mkdir() failure Signed-off-by: Al Viro --- arch/s390/hypfs/hypfs_diag_fs.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/arch/s390/hypfs/hypfs_diag_fs.c b/arch/s390/hypfs/hypfs_diag_fs.c index 00a6d370a2803..280266a74f378 100644 --- a/arch/s390/hypfs/hypfs_diag_fs.c +++ b/arch/s390/hypfs/hypfs_diag_fs.c @@ -208,6 +208,8 @@ static int hypfs_create_cpu_files(struct dentry *cpus_dir, void *cpu_info) snprintf(buffer, TMP_SIZE, "%d", cpu_info__cpu_addr(diag204_get_info_type(), cpu_info)); cpu_dir = hypfs_mkdir(cpus_dir, buffer); + if (IS_ERR(cpu_dir)) + return PTR_ERR(cpu_dir); rc = hypfs_create_u64(cpu_dir, "mgmtime", cpu_info__acc_time(diag204_get_info_type(), cpu_info) - cpu_info__lp_time(diag204_get_info_type(), cpu_info));