March 2025 - Linux-stable-mirror

[PATCH AUTOSEL 5.15 1/6] pm: cpupower: bench: Prevent NULL dereference on malloc failure

by Sasha Levin

From: Zhongqiu Han <quic_zhonhan(a)quicinc.com> [ Upstream commit 208baa3ec9043a664d9acfb8174b332e6b17fb69 ] If malloc returns NULL due to low memory, 'config' pointer can be NULL. Add a check to prevent NULL dereference. Link: https://lore.kernel.org/r/20250219122715.3892223-1-quic_zhonhan@quicinc.com Signed-off-by: Zhongqiu Han <quic_zhonhan(a)quicinc.com> Signed-off-by: Shuah Khan <skhan(a)linuxfoundation.org> Signed-off-by: Sasha Levin <sashal(a)kernel.org> --- tools/power/cpupower/bench/parse.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/tools/power/cpupower/bench/parse.c b/tools/power/cpupower/bench/parse.c index e63dc11fa3a53..48e25be6e1635 100644 --- a/tools/power/cpupower/bench/parse.c +++ b/tools/power/cpupower/bench/parse.c @@ -120,6 +120,10 @@ FILE *prepare_output(const char *dirname) struct config *prepare_default_config() { struct config *config = malloc(sizeof(struct config)); + if (!config) { + perror("malloc"); + return NULL; + } dprintf("loading defaults\n"); -- 2.39.5

2 days, 8 hours

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[PATCH AUTOSEL 6.1 1/6] pm: cpupower: bench: Prevent NULL dereference on malloc failure

by Sasha Levin

From: Zhongqiu Han <quic_zhonhan(a)quicinc.com> [ Upstream commit 208baa3ec9043a664d9acfb8174b332e6b17fb69 ] If malloc returns NULL due to low memory, 'config' pointer can be NULL. Add a check to prevent NULL dereference. Link: https://lore.kernel.org/r/20250219122715.3892223-1-quic_zhonhan@quicinc.com Signed-off-by: Zhongqiu Han <quic_zhonhan(a)quicinc.com> Signed-off-by: Shuah Khan <skhan(a)linuxfoundation.org> Signed-off-by: Sasha Levin <sashal(a)kernel.org> --- tools/power/cpupower/bench/parse.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/tools/power/cpupower/bench/parse.c b/tools/power/cpupower/bench/parse.c index e63dc11fa3a53..48e25be6e1635 100644 --- a/tools/power/cpupower/bench/parse.c +++ b/tools/power/cpupower/bench/parse.c @@ -120,6 +120,10 @@ FILE *prepare_output(const char *dirname) struct config *prepare_default_config() { struct config *config = malloc(sizeof(struct config)); + if (!config) { + perror("malloc"); + return NULL; + } dprintf("loading defaults\n"); -- 2.39.5

2 days, 8 hours

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[PATCH AUTOSEL 6.6 1/9] pm: cpupower: bench: Prevent NULL dereference on malloc failure

by Sasha Levin

From: Zhongqiu Han <quic_zhonhan(a)quicinc.com> [ Upstream commit 208baa3ec9043a664d9acfb8174b332e6b17fb69 ] If malloc returns NULL due to low memory, 'config' pointer can be NULL. Add a check to prevent NULL dereference. Link: https://lore.kernel.org/r/20250219122715.3892223-1-quic_zhonhan@quicinc.com Signed-off-by: Zhongqiu Han <quic_zhonhan(a)quicinc.com> Signed-off-by: Shuah Khan <skhan(a)linuxfoundation.org> Signed-off-by: Sasha Levin <sashal(a)kernel.org> --- tools/power/cpupower/bench/parse.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/tools/power/cpupower/bench/parse.c b/tools/power/cpupower/bench/parse.c index e63dc11fa3a53..48e25be6e1635 100644 --- a/tools/power/cpupower/bench/parse.c +++ b/tools/power/cpupower/bench/parse.c @@ -120,6 +120,10 @@ FILE *prepare_output(const char *dirname) struct config *prepare_default_config() { struct config *config = malloc(sizeof(struct config)); + if (!config) { + perror("malloc"); + return NULL; + } dprintf("loading defaults\n"); -- 2.39.5

2 days, 8 hours

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[PATCH AUTOSEL 6.12 01/13] pm: cpupower: bench: Prevent NULL dereference on malloc failure

by Sasha Levin

From: Zhongqiu Han <quic_zhonhan(a)quicinc.com> [ Upstream commit 208baa3ec9043a664d9acfb8174b332e6b17fb69 ] If malloc returns NULL due to low memory, 'config' pointer can be NULL. Add a check to prevent NULL dereference. Link: https://lore.kernel.org/r/20250219122715.3892223-1-quic_zhonhan@quicinc.com Signed-off-by: Zhongqiu Han <quic_zhonhan(a)quicinc.com> Signed-off-by: Shuah Khan <skhan(a)linuxfoundation.org> Signed-off-by: Sasha Levin <sashal(a)kernel.org> --- tools/power/cpupower/bench/parse.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/tools/power/cpupower/bench/parse.c b/tools/power/cpupower/bench/parse.c index e63dc11fa3a53..48e25be6e1635 100644 --- a/tools/power/cpupower/bench/parse.c +++ b/tools/power/cpupower/bench/parse.c @@ -120,6 +120,10 @@ FILE *prepare_output(const char *dirname) struct config *prepare_default_config() { struct config *config = malloc(sizeof(struct config)); + if (!config) { + perror("malloc"); + return NULL; + } dprintf("loading defaults\n"); -- 2.39.5

2 days, 8 hours

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[PATCH AUTOSEL 6.13 01/16] srcu: Force synchronization for srcu_get_delay()

by Sasha Levin

From: "Paul E. McKenney" <paulmck(a)kernel.org> [ Upstream commit d31e31365b5b6c0cdfc74d71be87234ced564395 ] Currently, srcu_get_delay() can be called concurrently, for example, by a CPU that is the first to request a new grace period and the CPU processing the current grace period. Although concurrent access is harmless, it unnecessarily expands the state space. Additionally, all calls to srcu_get_delay() are from slow paths. This commit therefore protects all calls to srcu_get_delay() with ssp->srcu_sup->lock, which is already held on the invocation from the srcu_funnel_gp_start() function. While in the area, this commit also adds a lockdep_assert_held() to srcu_get_delay() itself. Reported-by: syzbot+16a19b06125a2963eaee(a)syzkaller.appspotmail.com Signed-off-by: Paul E. McKenney <paulmck(a)kernel.org> Cc: Alexei Starovoitov <ast(a)kernel.org> Cc: Andrii Nakryiko <andrii(a)kernel.org> Cc: Peter Zijlstra <peterz(a)infradead.org> Cc: Kent Overstreet <kent.overstreet(a)linux.dev> Cc: <bpf(a)vger.kernel.org> Signed-off-by: Boqun Feng <boqun.feng(a)gmail.com> Signed-off-by: Sasha Levin <sashal(a)kernel.org> --- kernel/rcu/srcutree.c | 11 ++++++++++- 1 file changed, 10 insertions(+), 1 deletion(-) diff --git a/kernel/rcu/srcutree.c b/kernel/rcu/srcutree.c index 5e2e534647946..c5419e97bd97b 100644 --- a/kernel/rcu/srcutree.c +++ b/kernel/rcu/srcutree.c @@ -647,6 +647,7 @@ static unsigned long srcu_get_delay(struct srcu_struct *ssp) unsigned long jbase = SRCU_INTERVAL; struct srcu_usage *sup = ssp->srcu_sup; + lockdep_assert_held(&ACCESS_PRIVATE(ssp->srcu_sup, lock)); if (srcu_gp_is_expedited(ssp)) jbase = 0; if (rcu_seq_state(READ_ONCE(sup->srcu_gp_seq))) { @@ -674,9 +675,13 @@ static unsigned long srcu_get_delay(struct srcu_struct *ssp) void cleanup_srcu_struct(struct srcu_struct *ssp) { int cpu; + unsigned long delay; struct srcu_usage *sup = ssp->srcu_sup; - if (WARN_ON(!srcu_get_delay(ssp))) + spin_lock_irq_rcu_node(ssp->srcu_sup); + delay = srcu_get_delay(ssp); + spin_unlock_irq_rcu_node(ssp->srcu_sup); + if (WARN_ON(!delay)) return; /* Just leak it! */ if (WARN_ON(srcu_readers_active(ssp))) return; /* Just leak it! */ @@ -1102,7 +1107,9 @@ static bool try_check_zero(struct srcu_struct *ssp, int idx, int trycount) { unsigned long curdelay; + spin_lock_irq_rcu_node(ssp->srcu_sup); curdelay = !srcu_get_delay(ssp); + spin_unlock_irq_rcu_node(ssp->srcu_sup); for (;;) { if (srcu_readers_active_idx_check(ssp, idx)) @@ -1849,7 +1856,9 @@ static void process_srcu(struct work_struct *work) ssp = sup->srcu_ssp; srcu_advance_state(ssp); + spin_lock_irq_rcu_node(ssp->srcu_sup); curdelay = srcu_get_delay(ssp); + spin_unlock_irq_rcu_node(ssp->srcu_sup); if (curdelay) { WRITE_ONCE(sup->reschedule_count, 0); } else { -- 2.39.5

2 days, 8 hours

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[PATCH AUTOSEL 6.14 01/18] srcu: Force synchronization for srcu_get_delay()

by Sasha Levin

From: "Paul E. McKenney" <paulmck(a)kernel.org> [ Upstream commit d31e31365b5b6c0cdfc74d71be87234ced564395 ] Currently, srcu_get_delay() can be called concurrently, for example, by a CPU that is the first to request a new grace period and the CPU processing the current grace period. Although concurrent access is harmless, it unnecessarily expands the state space. Additionally, all calls to srcu_get_delay() are from slow paths. This commit therefore protects all calls to srcu_get_delay() with ssp->srcu_sup->lock, which is already held on the invocation from the srcu_funnel_gp_start() function. While in the area, this commit also adds a lockdep_assert_held() to srcu_get_delay() itself. Reported-by: syzbot+16a19b06125a2963eaee(a)syzkaller.appspotmail.com Signed-off-by: Paul E. McKenney <paulmck(a)kernel.org> Cc: Alexei Starovoitov <ast(a)kernel.org> Cc: Andrii Nakryiko <andrii(a)kernel.org> Cc: Peter Zijlstra <peterz(a)infradead.org> Cc: Kent Overstreet <kent.overstreet(a)linux.dev> Cc: <bpf(a)vger.kernel.org> Signed-off-by: Boqun Feng <boqun.feng(a)gmail.com> Signed-off-by: Sasha Levin <sashal(a)kernel.org> --- kernel/rcu/srcutree.c | 11 ++++++++++- 1 file changed, 10 insertions(+), 1 deletion(-) diff --git a/kernel/rcu/srcutree.c b/kernel/rcu/srcutree.c index b83c74c4dcc0d..2d8f3329023c5 100644 --- a/kernel/rcu/srcutree.c +++ b/kernel/rcu/srcutree.c @@ -647,6 +647,7 @@ static unsigned long srcu_get_delay(struct srcu_struct *ssp) unsigned long jbase = SRCU_INTERVAL; struct srcu_usage *sup = ssp->srcu_sup; + lockdep_assert_held(&ACCESS_PRIVATE(ssp->srcu_sup, lock)); if (srcu_gp_is_expedited(ssp)) jbase = 0; if (rcu_seq_state(READ_ONCE(sup->srcu_gp_seq))) { @@ -674,9 +675,13 @@ static unsigned long srcu_get_delay(struct srcu_struct *ssp) void cleanup_srcu_struct(struct srcu_struct *ssp) { int cpu; + unsigned long delay; struct srcu_usage *sup = ssp->srcu_sup; - if (WARN_ON(!srcu_get_delay(ssp))) + spin_lock_irq_rcu_node(ssp->srcu_sup); + delay = srcu_get_delay(ssp); + spin_unlock_irq_rcu_node(ssp->srcu_sup); + if (WARN_ON(!delay)) return; /* Just leak it! */ if (WARN_ON(srcu_readers_active(ssp))) return; /* Just leak it! */ @@ -1102,7 +1107,9 @@ static bool try_check_zero(struct srcu_struct *ssp, int idx, int trycount) { unsigned long curdelay; + spin_lock_irq_rcu_node(ssp->srcu_sup); curdelay = !srcu_get_delay(ssp); + spin_unlock_irq_rcu_node(ssp->srcu_sup); for (;;) { if (srcu_readers_active_idx_check(ssp, idx)) @@ -1849,7 +1856,9 @@ static void process_srcu(struct work_struct *work) ssp = sup->srcu_ssp; srcu_advance_state(ssp); + spin_lock_irq_rcu_node(ssp->srcu_sup); curdelay = srcu_get_delay(ssp); + spin_unlock_irq_rcu_node(ssp->srcu_sup); if (curdelay) { WRITE_ONCE(sup->reschedule_count, 0); } else { -- 2.39.5

2 days, 8 hours

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[PATCH AUTOSEL 5.10] umount: Allow superblock owners to force umount

by Sasha Levin

From: Trond Myklebust <trond.myklebust(a)hammerspace.com> [ Upstream commit e1ff7aa34dec7e650159fd7ca8ec6af7cc428d9f ] Loosen the permission check on forced umount to allow users holding CAP_SYS_ADMIN privileges in namespaces that are privileged with respect to the userns that originally mounted the filesystem. Signed-off-by: Trond Myklebust <trond.myklebust(a)hammerspace.com> Link: https://lore.kernel.org/r/12f212d4ef983714d065a6bb372fbb378753bf4c.17423151… Acked-by: "Eric W. Biederman" <ebiederm(a)xmission.com> Signed-off-by: Christian Brauner <brauner(a)kernel.org> Signed-off-by: Sasha Levin <sashal(a)kernel.org> --- fs/namespace.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/fs/namespace.c b/fs/namespace.c index 7e67db7456b3d..2f97112657adc 100644 --- a/fs/namespace.c +++ b/fs/namespace.c @@ -1716,6 +1716,7 @@ static inline bool may_mandlock(void) static int can_umount(const struct path *path, int flags) { struct mount *mnt = real_mount(path->mnt); + struct super_block *sb = path->dentry->d_sb; if (!may_mount()) return -EPERM; @@ -1725,7 +1726,7 @@ static int can_umount(const struct path *path, int flags) return -EINVAL; if (mnt->mnt.mnt_flags & MNT_LOCKED) /* Check optimistically */ return -EINVAL; - if (flags & MNT_FORCE && !capable(CAP_SYS_ADMIN)) + if (flags & MNT_FORCE && !ns_capable(sb->s_user_ns, CAP_SYS_ADMIN)) return -EPERM; return 0; } -- 2.39.5

2 days, 8 hours

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[PATCH AUTOSEL 5.15] umount: Allow superblock owners to force umount

by Sasha Levin

From: Trond Myklebust <trond.myklebust(a)hammerspace.com> [ Upstream commit e1ff7aa34dec7e650159fd7ca8ec6af7cc428d9f ] Loosen the permission check on forced umount to allow users holding CAP_SYS_ADMIN privileges in namespaces that are privileged with respect to the userns that originally mounted the filesystem. Signed-off-by: Trond Myklebust <trond.myklebust(a)hammerspace.com> Link: https://lore.kernel.org/r/12f212d4ef983714d065a6bb372fbb378753bf4c.17423151… Acked-by: "Eric W. Biederman" <ebiederm(a)xmission.com> Signed-off-by: Christian Brauner <brauner(a)kernel.org> Signed-off-by: Sasha Levin <sashal(a)kernel.org> --- fs/namespace.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/fs/namespace.c b/fs/namespace.c index 22af4b6c737f4..642baef4d9aaa 100644 --- a/fs/namespace.c +++ b/fs/namespace.c @@ -1734,6 +1734,7 @@ static void warn_mandlock(void) static int can_umount(const struct path *path, int flags) { struct mount *mnt = real_mount(path->mnt); + struct super_block *sb = path->dentry->d_sb; if (!may_mount()) return -EPERM; @@ -1743,7 +1744,7 @@ static int can_umount(const struct path *path, int flags) return -EINVAL; if (mnt->mnt.mnt_flags & MNT_LOCKED) /* Check optimistically */ return -EINVAL; - if (flags & MNT_FORCE && !capable(CAP_SYS_ADMIN)) + if (flags & MNT_FORCE && !ns_capable(sb->s_user_ns, CAP_SYS_ADMIN)) return -EPERM; return 0; } -- 2.39.5

2 days, 8 hours

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[PATCH AUTOSEL 6.1 1/2] fs: consistently deref the files table with rcu_dereference_raw()

by Sasha Levin

From: Mateusz Guzik <mjguzik(a)gmail.com> [ Upstream commit f381640e1bd4f2de7ccafbfe8703d33c3718aad9 ] ... except when the table is known to be only used by one thread. A file pointer can get installed at any moment despite the ->file_lock being held since the following: 8a81252b774b53e6 ("fs/file.c: don't acquire files->file_lock in fd_install()") Accesses subject to such a race can in principle suffer load tearing. While here redo the comment in dup_fd -- it only covered a race against files showing up, still assuming fd_install() takes the lock. Signed-off-by: Mateusz Guzik <mjguzik(a)gmail.com> Link: https://lore.kernel.org/r/20250313135725.1320914-1-mjguzik@gmail.com Signed-off-by: Christian Brauner <brauner(a)kernel.org> Signed-off-by: Sasha Levin <sashal(a)kernel.org> --- fs/file.c | 26 +++++++++++++++++--------- 1 file changed, 17 insertions(+), 9 deletions(-) diff --git a/fs/file.c b/fs/file.c index bc0c087b31bbd..2eccbb5dcd86a 100644 --- a/fs/file.c +++ b/fs/file.c @@ -362,17 +362,25 @@ struct files_struct *dup_fd(struct files_struct *oldf, struct fd_range *punch_ho old_fds = old_fdt->fd; new_fds = new_fdt->fd; + /* + * We may be racing against fd allocation from other threads using this + * files_struct, despite holding ->file_lock. + * + * alloc_fd() might have already claimed a slot, while fd_install() + * did not populate it yet. Note the latter operates locklessly, so + * the file can show up as we are walking the array below. + * + * At the same time we know no files will disappear as all other + * operations take the lock. + * + * Instead of trying to placate userspace racing with itself, we + * ref the file if we see it and mark the fd slot as unused otherwise. + */ for (i = open_files; i != 0; i--) { - struct file *f = *old_fds++; + struct file *f = rcu_dereference_raw(*old_fds++); if (f) { get_file(f); } else { - /* - * The fd may be claimed in the fd bitmap but not yet - * instantiated in the files array if a sibling thread - * is partway through open(). So make sure that this - * fd is available to the new process. - */ __clear_open_fd(open_files - i, new_fdt); } rcu_assign_pointer(*new_fds++, f); @@ -625,7 +633,7 @@ static struct file *pick_file(struct files_struct *files, unsigned fd) return NULL; fd = array_index_nospec(fd, fdt->max_fds); - file = fdt->fd[fd]; + file = rcu_dereference_raw(fdt->fd[fd]); if (file) { rcu_assign_pointer(fdt->fd[fd], NULL); __put_unused_fd(files, fd); @@ -1093,7 +1101,7 @@ __releases(&files->file_lock) */ fdt = files_fdtable(files); fd = array_index_nospec(fd, fdt->max_fds); - tofree = fdt->fd[fd]; + tofree = rcu_dereference_raw(fdt->fd[fd]); if (!tofree && fd_is_open(fd, fdt)) goto Ebusy; get_file(file); -- 2.39.5

2 days, 8 hours

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[PATCH AUTOSEL 6.6 1/2] fs: consistently deref the files table with rcu_dereference_raw()

by Sasha Levin

From: Mateusz Guzik <mjguzik(a)gmail.com> [ Upstream commit f381640e1bd4f2de7ccafbfe8703d33c3718aad9 ] ... except when the table is known to be only used by one thread. A file pointer can get installed at any moment despite the ->file_lock being held since the following: 8a81252b774b53e6 ("fs/file.c: don't acquire files->file_lock in fd_install()") Accesses subject to such a race can in principle suffer load tearing. While here redo the comment in dup_fd -- it only covered a race against files showing up, still assuming fd_install() takes the lock. Signed-off-by: Mateusz Guzik <mjguzik(a)gmail.com> Link: https://lore.kernel.org/r/20250313135725.1320914-1-mjguzik@gmail.com Signed-off-by: Christian Brauner <brauner(a)kernel.org> Signed-off-by: Sasha Levin <sashal(a)kernel.org> --- fs/file.c | 26 +++++++++++++++++--------- 1 file changed, 17 insertions(+), 9 deletions(-) diff --git a/fs/file.c b/fs/file.c index a178efc8cf4b5..f8cf6728c6a03 100644 --- a/fs/file.c +++ b/fs/file.c @@ -362,17 +362,25 @@ struct files_struct *dup_fd(struct files_struct *oldf, struct fd_range *punch_ho old_fds = old_fdt->fd; new_fds = new_fdt->fd; + /* + * We may be racing against fd allocation from other threads using this + * files_struct, despite holding ->file_lock. + * + * alloc_fd() might have already claimed a slot, while fd_install() + * did not populate it yet. Note the latter operates locklessly, so + * the file can show up as we are walking the array below. + * + * At the same time we know no files will disappear as all other + * operations take the lock. + * + * Instead of trying to placate userspace racing with itself, we + * ref the file if we see it and mark the fd slot as unused otherwise. + */ for (i = open_files; i != 0; i--) { - struct file *f = *old_fds++; + struct file *f = rcu_dereference_raw(*old_fds++); if (f) { get_file(f); } else { - /* - * The fd may be claimed in the fd bitmap but not yet - * instantiated in the files array if a sibling thread - * is partway through open(). So make sure that this - * fd is available to the new process. - */ __clear_open_fd(open_files - i, new_fdt); } rcu_assign_pointer(*new_fds++, f); @@ -625,7 +633,7 @@ static struct file *pick_file(struct files_struct *files, unsigned fd) return NULL; fd = array_index_nospec(fd, fdt->max_fds); - file = fdt->fd[fd]; + file = rcu_dereference_raw(fdt->fd[fd]); if (file) { rcu_assign_pointer(fdt->fd[fd], NULL); __put_unused_fd(files, fd); @@ -1095,7 +1103,7 @@ __releases(&files->file_lock) */ fdt = files_fdtable(files); fd = array_index_nospec(fd, fdt->max_fds); - tofree = fdt->fd[fd]; + tofree = rcu_dereference_raw(fdt->fd[fd]); if (!tofree && fd_is_open(fd, fdt)) goto Ebusy; get_file(file); -- 2.39.5

2 days, 8 hours

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